<> Diversity

our earth is teeming with life. approximately 1.8 million known types of organisms (living things) on the earth have been described and Sorting out named. scientists estimate 10–30 million other kinds of living things that haven’t even been discovered yet. scientists use classifi cation 2 to organise this diversity of life forms (biodiversity) in a logical fashion. biodiversity classifi cation is an example of a system that scientists have created, and continue to create, to help us better understand the world.

2.1 2.2 How do scientists Why do scientists classify? organise life?

Until the 1960s, any group of scientists could land on 1 name three resolutions or rules that scientists In 2010, six new Antarctic organisms were discovered. the Antarctic continent to do research. Often, the groups might have to agree to before they can do Although these organisms look like plants, they are research at the antarctic. would be researching the same organism but call it by classifi ed as animals. The ‘sea whips’ or ‘sea fans’ different names. Each would publish their results in 2 find out which countries signed the antarctic are similar to the corals found in the warm tropical treaty. their own language. The scientists needed an organised waters of other oceans, which is why the scientists ➔ Fig 2.3 The orca is one of our closest living relatives. system to help them share the results of their efforts. 3 do you think the antarctic treaty protects only were surprised to fi nd them in the icy waters of the These days, all visitors to the Antarctic work under a living things? explain your answer. Antarctic. Like the coral reefs, these tiny animal common treaty, working together to conserve every type polyps form colonies surrounded by hard scales that 2.3 Where do I fi t in? of plant and animal on this very special continent. ➔ Fig 2.1 A naming system for living things helps scientists to share their research. stand upright, gradually fl attening and branching out like a fan. A colony can grow to a metre high and a metre across, but only a few centimetres thick. They may be brightly coloured, often red, purple or yellow. The orca or Orcunus orca is one of our closest living relatives in the Antarctic. Orcas are highly 1 Tauroprimnoa austasensis was named because the social animals, often travelling in large families, researcher thought it looked like a bull. can you fi nd each family with their own range of sounds and a hint in the name? hunting techniques. Although Orcas have large 2 name two characteristics that might make you think teeth (up to 4 centimetres long) they do not chew these organisms are plants instead of animals. their food. Instead, they tend to swallow it whole. 3 if you had to divide your class into two groups, what Orcas are very protective of their young, nursing characteristic would you use to decide on the groups? them with milk from their mammary glands. As try to fi nd four different characteristics. soon as the young are old enough, the adults teach them to hunt fi sh, seals and seabirds in the freezing ➔ Fig 2.2 These plant- like organisms are ice-capped waters of the Antarctic. See Figure 2.2 actually animals. at left. 1 with a partner, brainstorm the characteristics you think of when you hear the word ‘animal’. 2 which, if any, of the characteristics you brainstormed SAMPLE would you use to describe yourself? 3 which of the orca’s characteristics could you use to describe yourself? in what ways is the orca different to you?

44 chapter 2 • sorting oUt biodiversity chapter 2 • sorting oUt biodiversity 45 Early classification methods

Early humans first classified plants by learning which Why do scientists classify? plants were edible and which were poisonous. A new plant or animal discovered by humans was (and still is) 2.1 tested and put into a group. Some plants were found Every year, scientists are discovering plants and animals that have never been seen to help sick people and others were poisonous. Some before. What if you were to find a neworganism at your school? How would you animals could produce foods (e.g. milk and eggs). Each know that no one else had discovered it before you? Could you describe it so that generation of scientists worked to improve how these people on the other side of the world understood what it looked like and how it groups were classified. behaved? How would you know if it was alive? The Greek philosopher Aristotle (384–322 bce) is considered by many to be the grandfather of classification. He found that each small township near his home had its own list of favourite plants and animals,

described and ordered for its own purposes. He decided ➔➔ Fig 2.5 The mature pine tree looks very different from its sapling. that this information should be shared and he set about <> finding a logical way to collect it. He sent his students out to gather local samples and stories. Over 500 types He suggested that each scientist needed to observe of plant and animal were collected and arranged in order an organism over the whole of its lifespan. Augustus of importance, according to where they lived and the Who am I? Quirinus Rivinus (1652–1723) and Joseph Pitton de shapes of their bodies. Aristotle ordered them from what Choose a partner to work with. Describe an animal to your partner—make sure you don’t use the animal’s Tournefort (1656–1708) both suggested using a hierarchy he thought was least important (rocks) to the most name. Your partner should try to draw the animal you describe. How accurate are they? of names. This meant starting with large general groups important (wild animals, men, kings, fallen angels, (like plants and animals) and then making each group Now draw an animal while your partner tries to guess what it is. How quickly did they guess your animal? angels and God). He divided animals into those with smaller and smaller depending on its characteristics. 1 How effective are word descriptions and drawings for communicating specific information about new blood (cats and dogs) and those that he thought had no Each organism had a long Latin name that described species? blood (insects, worms and shelled animals). the characteristics of each level of the hierarchy. For 2 What are the problems you can identify? For many years, other scientists used Aristotle’s example, a human would be described as an animal that 3 How might some of these problems have been overcome in more recent times? classification system. Nearly 2000 years later, early breathes air, lives on land, has two legs and two arms, explorers travelling to new lands found more new and can give birth (if female) to live young that drink milk different species—too many to fit into Aristotle’s 500 from their mother, has body hair, stands upright, uses The history of classification classification groups. They also questioned some of the tools and can speak. All this would have been written groupings—were rocks alive in Latin and the classification Early scientists didn’t have the technologies to make and should angels and God used by all educated people or send exact images of their discoveries. Most of their be included in this system? in the 17th century. Over the next hundred communication was written as papers or letters, sent Carolus Linnaeus (1707–1778) years a number of scientists around the world to other scientists. Many scientists tried these classification developed new ways of communicated in Latin, the ancient language from systems but found their describing and grouping which many European languages have come. They descriptions to be too long. organisms. Each scientist had to make illustrations and written descriptions of He decided a simpler system would publish their ideas the plants and animals that they saw and not all of was needed. He changed the in letters or books for other them were great artists. Often, without knowing it, descriptions to single words scientists to see. two scientists described the same organism that was and reduced the number of at different stages of its life. Imagine finding a tadpole Andrea Caesalpino (1519– classification groups to seven. and a frog for the first time—how would you know they 1603) suggested classifying Linnaeus’s system is still were the same animal? To devise a useful classification plants into groups according used today. It is occasionally system, scientists had to find a way to communicate that to their trunks and fruits. modified as new organisms would make misunderstandings less likely. They needed John Ray (1627–1705) pointed to agree on common words SAMPLEthey could use to describe are discovered and as we learn out that some plants looked more about the organisms we certain characteristics, common languages for scientific very different when they already know. papers and common processes for finding, describing were saplings than when ➔➔ Fig 2.4 Early scientists used illustrations to help them communicate. and communicating their work. they were large trees. ➔➔Fig 2.6 Carolus Linnaeus.

46 C hapter 2 • sorting out biodiversity Unit 2.1 • why do scientists classify? 47 practivity 2.1 The fi rst person to discover microscopic organisms was a Dutch scientist named Antonie The great Guzzlemobile van Leeuwenhoek (pronounced debate ‘LAY-ven-hock’), in the late 17th century. His fi rst discoveries gave him quite a shock. One day, van Leeuwenhoek noticed that his local water supply looked greenish and had begun to smell. He decided to look at a drop of the water with the microscope he had just made. At fi rst, he saw plant- ➔ Fig 2.10 A Guzzlemobile. like things containing long strands and tiny green globules a guzzlemobile has been found on a planet similar fl oating gently about. But mixed to the earth. two groups of scientists are arguing in among the globules were a about whether it is alive or not. host of tiny creatures (that he 1 work in a group of four, divided into pairs. one named ‘animalcules’) darting pair has to argue in favour of a guzzlemobile to and fro. No doubt he began being a living creature. the other pair has to to wonder what he had been argue that it is not alive. drinking every day! 2 each pair has 5 minutes to come up with a ‘If these tiny creatures lived in list of characteristics that support whether the water’, he thought, ‘I wonder if guzzlemobile is living or not. ➔ Fig 2.7 Part of Linnaeus’s classifi cation system. they live inside us?’ He then examined the plaque 3 when the time is up, have a class discussion between his own teeth. He also collected plaque from about whether this new ‘creature’ is alive or not. discovery of microworlds some other people (including one man who had never ➔ Fig 2.9 The rainforests of Brazil contain many undiscovered plant species. After the invention of the fi rst crude microscopes in cleaned his teeth in his life). If the water-borne the 17th and 18th centuries, science took off in a new organisms looked frightening, imagine how van direction. Fascinating tiny creatures that nobody had Leeuwenhoek felt when he saw enormous numbers of Finding new species ever seen before were being discovered all over the tiny organisms swimming around in the material taken What do you know about You might think that scientists have identifi ed all living world. New systems were needed to make room for from his own mouth. Van Leeuwenhoek is thought to things by now. They’ve been actively fi nding and classifying the history of classifi cation? these organisms. be the fi rst person ever to see bacteria. new organisms for hundreds of years. In fact, we will possibly never stop fi nding new types of organism, and ➔ Fig 2.8 (a) Dental plaque contains bacteria. (b) What van Leeuwenhoek saw that gave him nightmares: 1 the earliest scientists did not have pens or bacteria like these were living in his own mouth (as they do in yours). this is really good when you consider the benefi ts of such paper. how would they have passed on the biodiversity. information they received? how accurate Small groups of scientists are trying to fi nd undiscovered would it have been? plants in Brazilian rainforests before they are destroyed 2 aristotle was one of the fi rst scientists to by logging and farming. Often they are supported by try to gather information from wide regions. large pharmaceutical companies from other countries. what method did he use to organise all the Why would companies on the other side of the world be observations from his observers? interested in saving plants and animals in the rainforest? 3 why did carl linnaeus simplify the classifi cation One reason is that we may one day need these undiscovered system used by previous scientists? organisms. Many of the medications we currently use come 4 what is an ‘animalcule’? from organisms. The antibiotic penicillin was discovered SAMPLE 5 give two reasons scientists still classify from a type of mould; aspirin comes from a substance in organisms today. the bark of willow trees. The next painkiller could come ➔ a ➔ b from a small fungus in the rainforest, or from an insect that relies on the fungus for food.

48 chapter 2 • sorting oUt biodiversity Unit 2.1 • why do scientists classify? 49 Living and non-living Characteristics of living things r Living things rESPOND to stimuli When an animal realises it is being chased, like this antelope One of the fi rst decisions most scientists have to make It has taken many years of observation and discussion (Fig. 2.15), it runs. It is responding to stimuli (the sight and when classifying something for the fi rst time is if it for scientists to develop eight characteristics that all sound of a charging predator) or to changes in its environment (the sudden brush of leaves or movement of shadows). The living things—plants, animals and even microorganisms is alive. What does it mean to be alive? What is the sunfl owers shown in Figure 2.11 are responding to the changing difference between us and the chairs we sit on? Both like bacteria—have in common. To remember all eight stimulus of light and warmth. When you accidentally brush your plants and animals are considered to be alive. What do characteristics, just remember MR N GREWW. fi nger against something hot, like an iron, you pull back—your we have in common that makes us alive? body is responding to the stimulus of heat.

M Living things can MOVE by themselves n Living things need nUTRITION

Cats chase mice, birds fl ap their wings as All living things they fl y and fi sh swish their tails as they need nutrients to swim. Animal movements are easy to see. survive. Animals But do plants move? Look at the leaves obtain most of their on an indoor plant—they usually face the nutrients by eating window (a source of light). Turn the plant food and drinking. ➔ Fig 2.15 around so that the leaves face into a darker Plants absorb nutrients part of the room. In a few days, the leaves through their roots and fungi will again be facing the window. The leaves feed on decaying organisms. have moved by themselves. Sunfl owers turn Plants are autotrophs, E Living things EXCHANGE GASES with their environments their heads to follow the sun as it moves which means that they Plants and animals have organs across the sky each day. make their own food. and structures that allow them Animals and fungi are to exchange oxygen and other heterotrophs—they gases. Some animals, like rely on other living humans, use their lungs to things for food. inhale and then exhale. Other animals, like fi sh and axolotl (Fig. 2.16), have gills. Some w Living things require wATER animals, like worms, breathe All living things need water; through their skin. Bacteria are it is required for many jobs. ➔ Fig 2.11 ➔ Fig 2.13 different to plants and animals: For example, it transports substances in they do not have organs, but our bodies to where they are needed and they still exchange gases. it is involved in many important chemical Some types of bacteria die in r Living things can rEPRODUCE g Living things gROW as they get older reactions that must take place. In animals the presence of oxygen but use such as humans, it helps maintain and produce other gases. Living things can make new individuals that grow up to look like them. All living things grow during body temperature. No wonder a large Animals mate and produce offspring, plants produce seeds that grow into their lives. Mushrooms ➔ Fig 2.18 proportion of our body is water! new plants, and bacteria divide to produce more bacteria. Reproduction start off as tiny spores. is the process by which living things make new life. Humans are born as babies, developing into children, ➔ Fig 2.16 non-living or dead? teenagers and then adults. Insects hatch from eggs as Something classifi ed as living needs nutrition larvae, then metamorphose into adult insects. In every and water, and is able to move by itself, w Living things produce wASTES We, like other animals, case, living things, when fully take in food, water and reproduce, exchange gases, grow, respond to grown, resemble those who air to fuel our bodies. stimuli and produce wastes. produced them. Chemical reactions If something doesn’t have these characteristics, occur in our bodies and wastes are produced it would seem logical to assume that the thing as a result. We get rid is non-living. But, what about something that of these by exhaling, is dead? Something dead, such as a dried fl ower sweating, urinating and or an Egyptian mummy, was once living; when defecating (emptying SAMPLEour bowels). Plants it was alive it did have the characteristics of a get rid of their wastes living thing. Something that is non-living, such through their leaves. as a computer or your watch, never had these characteristics. ➔ Fig 2.12 ➔ Fig 2.14 ➔ Fig 2.17

50 chapter 2 • sorting oUt biodiversity Unit 2.1 • why do scientists classify? 51 What do you know about living and non-living? Encyclopedia of Life

1 the system scientists use to group things a with a partner or by yourself, decide if each of the divides them fi rst into two groups. what are the items meets the requirement to be classifi ed as ZooMing in Imagine how useful it would be to have a list of two groups? a living thing. every single living species on the Earth. Now 2 consider table 2.1. b decide if each should be classifi ed as living or imagine how long this list would take to compile non-living. given that there are nearly 2 million known species on our planet. ➔ Table 2.1 This seemingly impossible task has now been taken Eucalypt Leather roast water Paper robot wombat on by Edward O. Wilson, one of the world’s most tree belt chicken well known biologists. He is developing an online 1 Moves by database of all life on the Earth. The Encyclopedia itself of Life (EOL) aims to make all knowledge of the 2 Reproduces world’s known species freely available to all. The itself initiative was launched on 9 May 2007. As new

3 Requires species are discovered, they will be added to the nutrition database. Every species will have its own page, with links to all known information about that species. 4 Grows as it gets older The EOL will be a tool for scientists but also for students, teachers and the public to gain a better 5 Responds to changes in its understanding of all life on the Earth. Many environment people are saying that this is the most signifi cant development in the life sciences for more than 6 Exchanges 250 years. The EOL will be a global tool and will be gas (e.g. oxygen) used by people across the planet. The richness of life will only be one click away! 7 Produces wastes

8 Requires water Living or non-living?

3 are any of the items in table 2.1 dead? write a new mnemonic to help you remember the explain your answer. eight characteristics of living things. you may change 4 a mn emonic (pronounced ‘nem-on-ic’) is a memory the order of the characteristics to help you make aid. it is an especially good way to remember a list. a phrase. a mnemonic takes the fi rst letter of each word in 5 Use the characteristics of a living thing to describe a list and uses the letters to start words in a phrase. a bushfi re. for example, the colours of the rainbow (red, 6 is a bushfi re alive? explain your answer. orange, yellow, green, blue, indigo and violet) could be remembered using the phrase rich old yankees go bowling in vienna. SAMPLE

➔ Fig 2.19

52 Chapter 2 • sorting out biodiversity Unit 2.1 • why do scientists classify? 53 <> Diversity <> Diversity

13 look at table 2.2, showing the number of living things on the earth.

➔ Table 2.2 Types and numbers of living things on the Earth 2.1 Why do scientists classify? Percentage of total number of species number of species group estimated number described estimated to exist of living things Animals with internal 64 788 80 500 0.7% backbones (vertebrates) remember and understand 11 copy the table shown below. place the items in the following list in the correct columns: Animals without a backbone 1 359 365 6 755 830 61.8% 1 list the eight characteristics of living things. stewed apple, iPod, daffodil bulb, DVD, hairs (invertebrates) 2 what is an organism? in your brush, your teacher, shark’s tooth, Plants 297 857 390 800 3.6% 3 what is meant by the term ‘dead’? germs, soft drink bottle, your pet, silver chain, Fungi 98 998 1 500 000 13.7% 4 give an example of plants moving by dinosaur skeleton. themselves. Bacteria (Monera) 35 351 >1 200 500 11% Living non-living 5 what type of nutrition does a living plant need? Algae and protozoa (Protista) 28 871 >1 000 000 9.2% Currently 6 why is it important for scientists to use a dead living Total number of species 1 885 230 >10 927 630 100% common system to group all living things on the earth? Source: Chapman, A.D., Numbers of Living Species in Australia and the World, 2nd edn, September 2009 7 plants are described as living because they a how many species of plant are estimated have all eight of the characteristics of living to be on the earth? things. what gases do plants exchange with their environment? Analyse and evaluate b compare the number of known plant species with the total number of known Apply 12 one of the main contributors to the animal species (add animals without a Encyclopedia of Life is the Atlas of Living backbone and animals with a backbone 8 ‘biodiversity’ is the word used by scientists to Australia. do an internet search for the Atlas together). are you surprised with the describe a variety of different organisms in the of Living Australia and click on ‘explore’. result? explain. same region. why is it important to preserve from this page you can create a species list a large biodiversity of plants and animals in 14 do an internet search for an image of an and map for the area in which you live. the world? ‘interesting animal’. can you use the internet to fi nd how scientists classifi ed the animal 9 imagine that an unknown organism was a what is the most frequently (i.e. its scientifi c name)? discovered during a space mission and seen animal in your area? brought back to earth. briefl y outline two b what is the most Critical and creative thinking different methods that scientists could use to frequently seen decide if it was living or non-living. plant in your area? 15 design an experiment to show that plants are living things that respond to stimuli. 10 drawing accurate scientifi c diagrams of plants choose one stimulus only (such as reaction and animals is time consuming and diffi cult. to light or to lack of water) to investigate. this what method would be used by scientists stimulus is the experimental variable, so you today to show what an organism looks like? will need to change the variable in some way and control the rest of the variables in the experiment. Make a list of the equipment you would need.

SAMPLE<> Diversity 16 why was the invention of the microscope important to the development of the classifi cation system? how did it change the number of organisms for identifi cation, classifi cation and communication? ➔ Fig 2.20

54 Chapter 2 • sorting out biodiversity unit 2.1 • Why do sCientists CLassiFy? 55 Using dichotomous keys practivity 2.2 A key is a visual tool used in the Dr Redback’s family How do scientists organise life? classification of organisms. A key is often more useful than a list of Dr Redback loved to send out Christmas cards with the family photo on the 2.2 characteristics and similarities of front. One year, just for fun, he included a dichotomous key to help everyone Scientists group the millions of living things on the Earth so that they can see each group. A branched key (it looks identify all his family and pets. similarities and differences between organisms. This system helps scientists to like a tree) helps us to see how Use the picture of Dr Redback’s family and the communicate with each other when describing the characteristics and behaviour of a particular member of the group fits dichotomous key provided to work out who is who. living things. What characteristics do scientists use to divide the different animals in with all the rest. into groups? How big are the groups? How do scientists classify living things? One common type of key is called the dichotomous key (pronounced ‘dye-COT-o-muss’) as the branches always split into two (di = ‘two’). Scientists use this type of key to make simple ‘yes’ or ‘no’ decisions at Using keys each branch. For example, does the counter with all the games and movies sitting on When you visit an outdoor market, you may wander animal have fur (yes/no)? Does it have shelves. There might be several shelves of movies and around for some time before you find what you want. scales (yes/no)? Each answer leads to the one you want might be on a shelf of latest releases. A department store is more organised, with similar another branch and another question. items grouped together. If you were looking for the latest Scientists use a system similar to this to sort things into This key only works if the animal has movie on DVD, you would first locate the electronics groups, or classify them. The system makes the names already been identified by someone section. In that section you will often find the recordings and descriptions of organisms easier to find. else. A newly discovered organism would need to be studied first and then new branches added. ➔➔Fig 2.22 Dr Redback’s family. <> Department store design Long ears Bugs Hair all over body 1 With a partner, divide the items listed below into • Was it difficult to decide on Long tail Moggie six department store groupings of your choice. your six departments? Why Short ears Justify your choices. or why not? Short tail Buddy No feathers snowboard, CD, ‘miracle’ moisturiser, waterproof • Which items did you covering body tent, golf balls, jeans, mountain bike, T-shirt, atlas, have trouble placing into Unable to walk Scott cricket bat, Hacky Sack, laptop computer, sleeping departments? Why? bag, nail polish, digital alarm clock, TV celebrity • How did you end up agreeing No facial hair Peter poster, backpack, surfing magazine, ultrashine lip on a department for the Redback Hair covering family parts of body gloss, plasma TV, winter coat, wetsuit, R&B CD difficult-to-place items? Male box set, glitter eye shadow, perfume, swimming Facial hair Richard • Do you think a customer costume, MP3 player, travel book, CD player, visiting your store would find Able to walk hoodie jumper products easily? Red hair Vanessa 2 Divide the products in your six departments into • How was the layout of your Female smaller groups or ‘subdepartments’. store different from that of the Not red hair Stephanie 3 Draw a plan of your department store layout. Think other group? carefully about what departments you will put next Feathers • Did the other group find your to each other and why. SAMPLE covering body Flying animals Charlie department store plan easy to 4 Join up with another pair and ‘take them on a tour’ follow? What improvements through your department store. could you have made? ➔➔Fig 2.23 Dichotomous key for Dr Redback’s family. ➔➔Fig 2.21

56 C hapter 2 • sorting out diversity Unit 2.2 • how do scientists organise life? 57 <>

Dichotomous keys Finding the key Challenge Using what you have discovered about the Patterns, order and organisation The reverse listing key characteristics of living things, design your own As you no doubt found out in the Discovering Ideas activity Name ten things that a non-living

r own… dichotomous key. (page 56), it is quite possible to use different systems to thing could never do. u classify or group similar things. One system is not necessarily Questioning and predicting ➔➔Fig 2.24 The ‘what if’ key better than another, just different. Scientists use the same Think about objects that could be sorted into What if living things did not exist? types of method to classify living things—they group together two groups; for example, you might like to use What would the Earth be like? sign yo Processing, analysing and evaluating living things that have similar characteristics. e snack foods, such as corn chips, flavoured chips d or plain chips. 1 Draw a dichotomous key to show how you grouped The question key the objects. Thinkers Keys The answer is ‘single-celled Planning and conducting 2 How hard was it to divide your objects into different organism’. Think of five questions Thinkers Keys were first introduced by Australian educator • What similarities or differences can you groups? Could you have used a better group of objects? that give only that answer. Tony Ryan in the 1980s. Thinkers Keys introduce different find to separate the objects into two groups? ways of higher order thinking by challenging us to think in The construction key • What other similarities or differences can you Communicating different ways. Try using the Thinkers Keys approach to think Use materials from around your find to separate them into further groups? Swap your dichotomous key with another group. How differently about life on the Earth. classroom to construct your own Keep dividing into two groups until each effectively have they constructed a dichotomous key? type of classification key. item is on its own. Ask them to evaluate your key. Which was the best dichotomous key designed in your class? What features made it the best key? The combination key Make a list of all of the attributes of a plant cell and animal cell. Combine the attributes of these two things to create a new and better What do you know about using keys? ➔➔Fig 2.26 A dichotomous key to help Wings Fring type of organism. identify 16 different types of beetle. Stripes No wings Frong The disadvantages key 1 What is a dichotomous key? 6 Design a dichotomous key to identify dinosaurs. Antennae Wings Frap Make a list of the possible You should research at least ten dinosaurs of the 2 Why is it called ‘dichotomous’? Spots disadvantages of classifying things Jurassic period (find out when this was), find drawings No wings Frip 3 What does the term ‘classifying’ mean? into groups. Suggest ways to correct of them and identify characteristics that could be used Round 4 Which of the following descriptions would be good Wings Fripe or eliminate each disadvantage. to classify them. Make up a table of their common Stripes to use to classify a group of birds in a dichotomous characteristics and look for common ones you could use No wings Frope The prediction key key? Give a reason why each one is or is not a good No antennae to build a dichotomous key for classifying them. Include Wings Frot method of classification: Predict what types of organism the names and pictures of the dinosaurs on the key. Spots might be discovered in the next a is eating bird seed No wings Frit 7 Use the dichotomous key in Figure 2.26 to help with the All beetles twenty years. b has a blue stripe above the eye following tasks. Wings Gring c has a wing span of 32 cm a Identify and name the four beetles in Figure 2.25. Stripes The alphabet key d has a broken leg No wings Grong b Draw a simple sketch of the following: Prepare a list of words from A to Z e is sitting on the ground Antennae i frope beetle Wings Grip that describe things that a living f has a high-pitched, bell-like song Spots ii gring beetle thing can do. g has brown tail feathers No wings Grop iii gripe beetle Oval 5 Draw a key that could be used to identify laboratory iv frong beetle Wings Gripe The commonality key equipment. Include these items: tripod stand, Stripes What do living things and non-living Bunsen burner, gauze mat, 50 mL beaker, 150 mL No wings Grope No antennae things have in common? beaker, 100 mL measuring cylinder, 10 mL measuring SAMPLE Wings Grot cylinder, 500 mL beaker, 500 mL measuring cylinder, Spots retort stand, clamp. No wings Grit ➔➔Fig 2.25

58 C hapter 2 • sorting out biodiversity Unit 2.2 • how do scientists organise life? 59 The Linnaean classifi cation system Kingdom: Animalia practivity 2.3 e.g. insect, fi sh, bird, lizard, kangaroo, fox, lion, jungle cat, domestic cat Deciding to use an enormous dichotomous key to Making a fi eld guide classify every living thing was largely the work of a man Phylum: Chordata scientists often use fi eld guides to determine the group named Carolus Linnaeus (1707–1778). His system of e.g. fi sh, bird, lizard, kangaroo, fox, to which an animal belongs. these guides are set out in a classifi cation, called the Linnaean taxonomy, is still lion, jungle cat, domestic cat tabular key where you read through the numbered options in used today. Class: Mammalia order. each item presents two options, and more information e.g. kangaroo, fox, lion, jungle cat, Linnaeus was born in Sweden in 1707 and he originally domestic cat is given at each step. eventually the animal can be identifi ed. studied medicine. However, his real interest was in 1 Use the information given to identify the class collecting plants and he went on many expeditions Order: Carnivora e.g. fox, lion, jungle cat, domestic cat of each of the animals shown. to other countries to collect native plants. To be able to make sense of all the plants he had collected from Family: Felidae Feathers present Aves 1 around the world, he designed a system to order and e.g. lion, jungle cat, domestic cat No feathers present Go to 2 name them. He worked as a professor at the University Hair or fur present Mammalia of Uppsala in Sweden and, in his spare time, arranged Genus: Felis 2 No hair or fur Go to 3 all the plants in the university garden according e.g. jungle cat, domestic cat to his new system of classifi cation. Fins present Pisces Species: catus 3 No fi ns present Go to 4 Linnaeus’s classifi cation system was extended from domestic cat just grouping plants to classifying all the kingdoms Has moist skin, no scales Amphibia ➔ Fig 2.28 The Linnaean classifi cation 4 of living organisms. system uses seven different levels. Has scales Reptilia It is used to give names to living things such as the domestic cat. 2 Use the information given about dr redback’s family in giving organisms a precise name practivity 2.2 on page 57 to create your own fi eld guide or tabular key. When you were younger, Linnaeus’s double-name system did you ever send a letter to Have you eaten a Musa sapientum lately or have they 23 Norton Stre t a friend with your address Boronia been too expensive to buy? And did you pat your Canis Melbourne on the back of the envelope A species is a group of organisms that Victoria familiaris this morning? These are the kinds of double Understanding scientifi c names written like Figure 2.27? look similar to each other. When they Australia name given to every living thing using the Linnaean Southern Hemisphere breed in natural conditions, their offspring The scientifi c names of animals usually come from Latin (and Earth classifi cation system. Solar System are fertile (in other words, they can also sometimes Greek) words. Why use Latin? The language of science Milky Way Galaxy ➔ Fig 2.27 Did you ever Our homes can easily be found by using only the two breed). Domestic cats belong to the one for many centuries was Latin. This enabled scientists who lived in The Universe address a letter like this? smallest groups in the address (the street and the species because they can breed together different countries and spoke different languages to use a common suburb). The information about the bigger and have kittens. language to communicate their work and discoveries. groups, like the Earth and the universe, If you read this address from the bottom up—from More than 500 000 organisms have already The words used describe physical features, behaviours and is not really necessary. In much the same ‘The Universe’ to the house number—it is a bit like a been given a double name (also called a even colours of organisms. Some basic understanding of Greek way, an organism can also be named classifi cation key. As you go up each level, it becomes binomial name) and can be easily found in and Latin will help you to interpret scientifi c names. Table 2.3 from the two last groupings on the easier to locate the sender. It is a bit like focusing in the Linnaean classifi cation system. contains some examples. on your house on Google Earth. You may start with the Linnaean dichotomous key—the genus and the species. whole country, but each country has states, then towns, ➔ Table 2.3 Some scientifi c words and their meanings suburbs and, fi nally, streets and buildings. In the double-name system, the Latin/greek root word English meaning Latin/greek root word English meaning The Linnaean dichotomous key for all living things genus group name always starts works in a similar way. It starts with large groups called with a capital letter. The Aculeat Spiny Ornitho Bird kingdoms, and then divides into smaller groups called second word is the species Arctus Bear Phascol Pouch name and it does not phyla. Each phylum has several classes. The classes Anatinus Duck-like Pus Foot have orders, and so on. There are seven different levels have a capital letter. to get to the fi nal name of each organism. They are The double name is Cinereus Grey Rufus Red kingdom, phylum, class, order, family, genus, species. always written using SAMPLEGloss Tongue Tachy Fast (Tip: Some people use the following mnemonic to italics (sloping letters). Hynchus Snout Chlamy Caped remember the Linnaean system: ‘King Phillip Crawled ➔ Fig 2.29 Musa sapientum is the Linnaean Macro Large Saurus Lizard Over Four Gooey Snails’.) name for a banana.

60 chapter 2 • sorting oUt biodiversity Unit 2.2 • how do scientists organise life? 61 Cells in living things What do you know about the Linnaean classification system? The discovery of microscopes changed the classification system. Instead of grouping only the large 1 Use the information in Table 2.3 to match the scientific plants and animals, scientists now had to include all names of the Australian animals with their pictures. the tiny living things they saw under a microscope. They could also consider much smaller details when a Macropus rufus grouping organisms according to features.

Building blocks of life ➔➔ Fig 2.31 The nerve cells of giant squid are up to 12 metres long! Cells are often called the building blocks of life. Think b Tachyglossus aculeatus of the way bricks are used to build a house. Cells build living things in a similar way. However, there are which carries all the instructions for staying alive. Often usually many more cells in living things than bricks (but not always) this genetic material is packaged into in a house: an adult human body is made up of about a small part of the cell called a nucleus. Each cell of 10 trillion (10 000 000 000 000) cells. Elephants have an animal or plant has a nucleus. All cells without a c Phascolarctus cinereus even more. Any living thing with more than one cell is nucleus (like bacteria) are in a separate group. Plant cells multicellular. As van Leeuwenhoek discovered, many have a special cell wall around them for extra support, living things, such as bacteria, consist of only one cell. while animal cells do not. This is one way scientists These are single-celled or unicellular. distinguish between plants and animals. Another way to Cells can usually only be seen through a microscope. distinguish between cells is whether they use sunlight d Ornithorhynchus anatinus Some are so tiny that 20 000 of them, placed end to end, to make their own nutrients (autotroph). Plant cells can would only be 1 centimetre long. Giant squid have nerve do this, but fungi (like mushrooms) need to absorb their cells that are up to 12 metres long! nutrients from other living things (heterotroph). The structures inside the cells give us information about how Armed with a new and bigger picture of life, scientists they work. set about the task of working out dichotomous keys e Chlamydosaurus kingii for a system that would include all living things. It is these small details that are used to divide up all living things in the first big groups called kingdoms. Parts of a cell Although the cells of different organisms might at first What do you know about appear quite different in shape, if you look closer at the parts that make them up, cells are actually quite cells in living things? similar. All cells have genetic material called DNA, 1 Name two characteristics of a plant cell. 2 What is a nucleus? 2 What do you think a Macroglossus aculeatus might 6 With the same idea in mind, why do taxonomists need 3 What is the role of a cell wall? look like? Sketch this imaginary animal, using Table 2.3 a very detailed system like the Linnaean classification 4 Name an organism made up of just to help. system to group living things? Cell wall one cell. 3 Who invented the naming system that is still used 7 What is the first level of the Linnaean classification 5 What does ‘multicellular’ mean? today to name living things? system under ‘All living things’? 6 What does ‘unicellular’ mean? 4 What are the seven groups that living things are 8 What does the word ‘species’ mean? 7 Why was the invention of the microscope divided into? Write them in order from largest to 9 Select three species of animal. For each animal: important to our understanding of living smallest level of organisation. a describe its appearance things? 5 Why would giving your address as ‘John Campbell, b give its common and scientific name. Southern Hemisphere, The Earth’ not be a good way to SAMPLE get many letters? Nucleus

➔➔ Fig 2.30 Simple animal (left), plant (middle) and bacterial (right) cells.

62 C hapter 2 • sorting out biodiversity Unit 2.2 • how do scientists organise life? 63 <> Diversity Where do I fit in? 2.3 2.2 How do scientists organise life? The animal kingdom contains a large range of organisms: from the tiniest fairy fly, where 50 could fit within 1 millimetre, to the giant blue whale, which is up to 33 m long— about the size of a house. Size is not a very suitable characteristic for classifying animals into groups, especially because most grow over time. So what characteristics Remember and understand Analyse and evaluate are chosen to group animals? And where do humans fit in this system? 1 Where do you find the largest cell?H ow big is it? 10 Identify some of the difficulties of using your 2 Why are most keys dichotomous? dichotomous key on the contents of someone else’s bag or pencil case. 3 Are most animals unicellular or multicellular? Explain your choice. 11 Research other types of classification key that can be used to identify organisms. Kingdoms 4 What are the advantages of using a <> dichotomous key? o 12 Download a copy of the collection of insects in The earliest taxonomists (scientists that classify Figure 2.31 from your obook. 5 List two characteristics that would divide living things) divided all living things into two your science class into two groups of a Cut out the pictures of the insects so you Grouping animals groups: plants and animals. As new technology approximately equal size. can move them around on your desk. such as microscopes developed, very small Type the word ‘animal’ into a search engine for images. 6 Empty your school bag or pencil case and b Working on your own, sort the insects organisms were discovered that did not fit into Print and cut out the images of 30 very different animals. design a dichotomous key of its contents. into groups based on some aspect of either of these groups. Scientists began to question their appearance. Justify your system of Decide on the most appropriate features for grouping the classification of other organisms such as Apply classification. these animals. For example, fat and thin tends to be mushrooms: did they really belong to the plant 7 Arrange these terms in order from the level c Compare your groupings with those of a related to lifestyle rather than the type of animal. group? After all, they looked different under the that contains the most number of organisms partner. Between the two of you, can you Use these groupings to come up with a dichotomous microscope and they didn’t produce their own food. think of other ways to classify the insects? to the level that contains the least number of key for your animals. These days, scientists generally agree on classifying organisms: family, kingdom, species, class, d With your partner, create a dichotomous Did anyone in the class use similar characteristics to living things into five large kingdoms based on: phylum, genus, order. key for this group of insects. you when grouping their animals? How do you think this • the structure of their cells 8 Make up a new mnemonic to remember the is similar or different to the way scientists would work? • how they obtain nutrients levels of classification. Critical and creative thinking • their general appearance. 9 Refer to Figure 2.22 (page 57) showing 13 Write a short story of 500 words to describe Dr Redback’s family. How might you adjust the chaos in a large library that operated with the dichotomous key if his ‘family’ included no system of classification. Try to make it Kingdom Animalia his sister, Melinda, and mother, Frances; he humorous. ➔➔a ➔➔Fig 2.32 Kingdom Animalia: All organisms in this kingdom are multicellular. Each cell stores had two daughters, Stef and Gemma (Stef 14 Propose a new system of classification for (a) The proboscis monkey (Nasalis its genetic material in a nucleus but doesn’t have a cell wall. wears glasses), and he had a pet lizard named organising life on the Earth. Which kingdom larvatus) has the biggest nose. Animals gain energy from other living things. We belong in this Stealth and not a bird named Charlie? would you be in? (b) Pangolin. (c) Goanna. (d) Port Jackson shark. (e) Damselfly. kingdom. Zoologists are the scientists who study animals.

➔➔b ➔➔c ➔➔e

➔➔Fig 2.31

<> Diversity SAMPLE➔➔d 15 a why was the invention of the dichotomous key important to the development of the classification system? b What are the limitations of a dichotomous key?

64 Chapter 2 • sorting out biodiversity Unit 2.3 • where do I fit in? 65 Kingdom Plantae Kingdom Monera

Plants include trees, vines, This kingdom is made up of the simplest and smallest living things. There are about bushes, ferns, mosses, weeds 75 000 different organisms in Kingdom Monera and they are all unicellular, and and grasses. They all gain energy have a cell wall but no nucleus. Bacteria are the most common in this kingdom. by making their own food from Many people think of bacteria as harmful to humans, but this is not always true. sunlight (autotrophs). They are Bacteria in the soil break down rubbish and wastes produced by animals (especially multicellular, but their cells have ➔ a ➔ b us). Without bacteria, we would be surrounded by mountains of smelly rubbish. a cell wall around the outside of Bacteria have been put to use by humans to make foods, such as cheese and yoghurt. the cell, as well as a nucleus inside ➔ d ➔ e Microbiologists are the scientists that study microorganisms in kingdoms the cell. Botanists are the scientists Monera and Protista. who study the plant kingdom.

➔ a ➔ b ➔ c ➔ c

➔ Fig 2.35 Kingdom Monera, as seen under a microscope: (a) Lactobacillus casei. (b) Streptococcus pyogenes. (c) Spirillum volutans.

➔ a ➔ b ➔ Fig 2.33 Kingdom Plantae: (a) The smelliest plant, the Raffl esia, is found in South-East Asia. Its fl ower can measure up to 90 centimetres across and weigh about 11 kilograms. It gives off a rotten meat odour when it blossoms, to attract insects. (b) Flowering gum. (c) Wheat. (d) Nepenthe. (e) Cactus. Kingdom Protista

There are about 55 000 species Kingdom Fungi of protist. Their cell structure is Kingdom Fungi includes mushrooms, toadstools, yeasts, puffballs, moulds and more complex than Monera. Often, truffl es. Some fungi grow in wood and in soil and develop from tiny spores. Fungi organisms that don’t fi t into any other do not make their own food. Instead, they feed on the remains of dead animals and kingdom will belong in Protista. They plants. Some fungi can cause diseases, such as tinea (athlete’s foot). Mycologists are may range in size from single-celled the scientists who study Kingdom Fungi. organisms to much larger ones, like kelp (seaweed). Plankton, the tiny sea creatures eaten in their millions ➔ a ➔ b ➔ c by whales, are part of this kingdom. ➔ c ➔ d Amoeba, microscopic organisms that change their shape to trap their food, SAMPLEalso belong to this group. ➔ Fig 2.36 Kingdom Protista, as seen under a microscope: (a) Amoeba. (b) Paramecium. ➔ Fig 2.34 Kingdom Fungi: (a) Mushrooms. (b) Mould. (c) Aspergillus conidiophores as seen under a microscope. (c) Giardia lamblia (d) Ophiocytium arbuscula.

66 chapter 2 • sorting oUt biodiversity Unit 2.3 • where do i fit in? 67 practivity 2.4 Classifying living things Giant squid dissection what you need: ‘sorting into Kingdoms’ worksheet Examining skeletons from your workbook or a3 card/paper, scissors, glue. released on the web ZooMing in Aim the scientist whose main role is to classify living things By Matthew Moore, 5:19PM BST 18 Jul 2008 to examine the skeletal structures of three marine organisms. is known as a taxonomist. in this activity, you become A giant squid has been dissected live on the internet the taxonomist. Materials for the fi rst time—and the gory 90 minute clip has 1 download the ‘sorting into Kingdoms’ worksheet. been released for public download. 1 fi sh (whole) (alternatively, this activity can be done online.) 1 prawn 1 The 39 st [nearly 250 kilogram] creature was 2 Use a double-page spread of your workbook (or a sheet 1 squid ➔ Fig 2.38 carved up by biologists in front of hundreds EXPEriMEnT 2.1 of a3 card or paper) to mark up a table with four columns. newspaper of onlookers and thousands of web viewers 3 label the columns ‘animalia’, ‘plantae’, ‘fungi’ and at Melbourne Museum in Victoria, dissecting board ‘other (Monera and protista)’. (don’t try to distinguish Australia. dissecting kit between Monera and protista.) pair of vinyl or latex gloves The team of scientists provided a 4 cut out each organism from the worksheet and paste running commentary as they revealed it into the correct column. the squid’s internal organs, including • always wear gloves when handling the animals. its three hearts and doughnut- • the animals must always be on the dissecting board when shaped brain. handling and dissecting. They also established the • scalpels are extremely sharp. Use with great care. What do you know about squid was a female, and • if cut, remove gloves and wash the cut under clean water. 2 kingdoms? cut into her stomach in an • apply antiseptic to the cut and cover with dressing. unsuccessful attempt to tell your teacher. ➔ Fig 2.39 discover her fi nal meal. 1 name four features of animals. Method discussion 2 name four features of Kingdom Monera. ➔ Fig 2.37 The giant squid is an invertebrate. 3 how is a protist different to a bacterium? 1 observe the external 1 consider the fi sh. 4 what is the difference between cells in Kingdom features of the fi sh. a where is the skeleton of the fi sh located? plantae and Kingdom fungi? 2 carefully cut the fi sh in half Many people in the audience held handkerchiefs b what is this type of lengthways so you can see in front of their faces because of the revolting smell. skeleton called? the internal skeleton. The rare creature was caught up in fi shing nets in 2 consider the prawn. 3 observe the skeleton of May, but this was the fi rst detailed inspection of its a where is the skeleton of Kingdom Animalia the fi sh. body. The corpse took three days to thaw. the prawn located? 5 internal or external skeleton? 4 feel the outside of the prawn Stretching to 40 ft [over 12 metres] in length, it was b what is this type of and then peel it. ➔ Fig 2.40 In the same way as creating any kind of dichotomous key, the longest giant squid ever captured in Australian skeleton called? 5 cut the prawn in half and dividing the animal kingdom into groups fi rst requires waters. 3 does the squid have a observe the insides. skeleton? a question. The system scientists use to divide animals But calamari connoisseurs hoping for a feast will 6 feel the outside of the squid into groups is based on their structure. The question is: 4 in which group of animals be disappointed; female squids are not fi t for human and then cut it in half. ‘Does this animal have an internal or external skeleton?’ consumption because of the amount of ammonia (vertebrate or invertebrate) 7 observe the inside of the Animals such as cats, humans and birds with an internal in their bodies. would you place each of the squid. organisms observed? why? skeleton (called an endoskeleton) are put in a group called After tests on the squid are complete it will be 5 what are you: a vertebrate or vertebrates. Because these animals often have a spinal sewn back together and put on display in an results an invertebrate? cord that threads its way between the vertebrate bones, ethanol solution at the museum. draw labelled diagrams of each the phylum is called Chordata. Other animals with an The full video of the dissectionSAMPLE is available to view specimen’s skeleton. Conclusion external skeleton (exoskeleton), such as beetles and and download from the Melbourne Museum website. what types of skeleton are 6 crabs, and those with no skeleton at all, such as slugs, possible? are known as invertebrates. Invertebrates dominate the Source: www.telegraph.co.uk/earth/earthnews/3347540/Giant-squid-dissection- ➔ Fig 2.41 released-on-the-web.html animal kingdom.

68 chapter 2 • sorting oUt biodiversity Unit 2.3 • where do i fit in? 69 Classes of vertebrate What do you know about Vertebrates are animals with a spine or backbone. Kingdom Animalia? Vertebrates as a group can be broken down into further The enigma of the echidna subgroups called classes. Scientists group vertebrates By Doug Stewart the strange animal 1 animals are divided into two main groups. according to: LiTErACy LAB before eating it. not until a what are the names of the groups? • their body covering one of the most remarkable sights that biologist peggy 1884 did the scientifi c b what do the names of these two groups mean? • how their young are born rismiller has seen in her years exploring the australian world learn, to its 2 give two examples of animals with an exoskeleton. • their body temperature. bush is that of an echidna sunbathing. the short-beaked amazement, that both echidna, or spiny anteater, ordinarily resembles a spiky 3 give two examples of animals with no skeleton at all. Vertebrates either have a constant body temperature platypuses and echidnas ball, like some kind of terrestrial sea urchin. to warm 4 what percentage of animals are invertebrates? (endotherm) or a body temperature that changes with laid eggs. up on a cool morning, however, it will stretch out on the the environment (ectotherm). 5 why do you think invertebrates are such a dominant ground ... and lift its spines to let in sunlight. ‘it’s amazing ... after mating, an group among animals? to see,’ rismiller says. ‘it looks like a rug with spines.’ adult female lays a 6 what is the world’s biggest known invertebrate? Class Mammalia single egg about the size of a fi ve-cent coin directly into her on a continent teeming with weird mammals, the pouch. the newborn puggle that hatches about ten days later 7 draw a sketch of the world’s biggest invertebrate Mammalia is a class of vertebrates well known to many echidna is one of the weirdest. it has a beak like a bird, stays in the pouch for several weeks to suckle from the milk and write down its dimensions, for example its people. Many of our pets belong to this class: horses, spines like a hedgehog, eggs like a reptile, the pouch its mother secretes. length and weight. dogs, cats, rabbits, guinea pigs and mice. We belong to of a marsupial and the lifespan of an elephant. elusive ... australians have adopted the short-beaked echidna as 8 why do you think dissecting a giant squid live on this class, too. and unpredictable, echidnas continue to perplex the the internet was so interesting to so many people? scientifi c world with their oddities. a national mascot of sorts ... the echidna’s total numbers are do you fi nd it interesting? explain. Mammals are animals with hair or fur and they have a unknown ... concerned that their future welfare is not assured, constant body temperature. Female mammals give birth along with the platypus, the echidna is the world’s australia has offi cially listed them as a protected species. to live young and feed their young with their own milk. only living monotreme, an order of egg-laying mammals found solely in australasia ... ‘echidna’ commonly refers Source: www.nwf.org/News-and-Magazines/National-Wildlife/Animals/Archives/2003/ The-Enigma-of-the-Echidna Class Mammalia can be further broken down into three to the short-beaked echidna, which is found across subgroups, as shown in Figure 2.42. The main feature australia. a second genus, the long-beaked echidna, ➔ Fig 2.42 The three subgroups of mammal. used to separate mammals is the way in which their lives in papua new guinea. 1 two different types of echidna exist today. where does young develop. each live, and how are they different? the fi rst detailed description of the echidna was 2 do you consider the echidna to be weird? explain. Mammals published in england in 1792. a decade later, another account included a drawing by captain william bligh, Marsupials 3 why do you think that scientists who had not seen who had feasted on roast echidna years earlier during an echidna for themselves might have believed pictures Young are born at a very a stopover in australia. bligh had the foresight to sketch to be false? early stage of development Development occurs in a pouch Young receive milk from a teat located in Class Aves ➔ a ➔ b the pouch All birds in Phylum Chordata belong in this class. Like mammals they are endotherms (having constant body temperatures). One of their main distinguishing Placentals characteristics (the way they differ from the other classes) is their Young develops inside Monotremes covering of feathers, and their scaly mother’s womb Young develop in legs. All animals in this class lay Young are well developed leathery shelled eggs eggs with a hard shell. when born Development occurs in a burrow Mother produces milk from after hatching mammary glands SAMPLE Young suckle from milk patches on mother’s abdomen ➔ Fig 2.43 Class Aves: (a) Vulture. (b) Cockatoo.

70 chapter 2 • sorting oUt biodiversity Unit 2.3 • where do i fit in? 71 Class Reptilia Class Pisces

The skin of reptiles, such as snakes and lizards, is usually covered in a layer Most fish are ectotherms. They are of fine scales. Reptiles use lungs to breathe, even if they live under water (sea covered in a layer of scales and most snakes). These animals are also ectotherms—we do not use the term ‘cold- have fins. They spend all their life in blooded’ to describe these animals because a lizard that has been lying in the water and so need gills for breathing. sun has very warm blood, even though at night its blood is cool. Fish are further grouped according to their skeleton. Sharks, rays and ➔➔Fig 2.44 Class Reptilia: (a) King brown snake. skates have a skeleton made entirely (b) Bearded dragon. (c) Gecko. of cartilage, while all other fish have bony skeletons. ➔➔a ➔➔b

➔➔Fig 2.46 Class Pisces: (a) Tuna. (b) Weedy seadragon. ➔➔c ➔➔d ➔➔a ➔➔b ➔➔c (c) Reef shark. (d) Manta ray.

practivity 2.5 Class Amphibia Who are the vertebrates? Like reptiles, amphibians are ectotherms; however, their skin is usually soft and slimy to touch. They lay their eggs, without shells, in water. For the first Vertebrate alphabet graffiti Jellyfish organiser for 2 on a full page, draw five ‘jellyfish’ vertebrates connected to the main group part of their life they have gills and live in the water. As they get older, lungs Note: Alternatively, this task could be (vertebrates), as shown in Figure develop and they become able to live on the land. The only remaining group completed as a webpage, with images A jellyfish graphic organiser is a good 2.47. of amphibians in Australia is frogs. In other parts of the world, caecilians and links to further information about way to show how subgroups make and salamanders may be found. each animal. up a whole. It can also be used to list 3 label each jellyfish with the class specific examples at the same time. names (fish, reptiles, amphibians, 1 divide the class into five groups, mammals and birds). each of which will be allocated one 1 individually, go around to each of 4 write a description of the class of vertebrate. the five sheets of vertebrates and characteristics of each class in the 2 label an A3 sheet of paper with the select six animals from each class. appropriate body of each jellyfish. name of your class of vertebrate. 5 place the six animals you selected 3 write the letters of the alphabet ➔➔Fig 2.47 A jellyfish organiser for vertebrates. along six tentacles on each jellyfish. down the left-hand side of the page. 4 for each letter, write the name of Vertebrates an animal that fits this category. 5 when finished, you will have the names of up to 26 different Birds Mammals Fish Reptiles Amphibians

vertebrates. Some categories will Eagle Sparrow Magpie Example Example Example Example be harder to fill than others. SAMPLE6 put up the finished sheets around the room. ➔➔a ➔➔b

➔➔Fig 2.45 Class Amphibia: (a) Growling grass frog. (b) Chinese giant salamander.

72 C hapter 2 • sorting out biodiversity Unit 2.3 • where do I fit in? 73 identifying invertebrates What do you know about classes of vertebrate? In the same way that vertebrates were classifi ed, invertebrates are also grouped by their characteristics. 1 seals have fi ns like fi sh and live on the land and in the 3 a fl ying fox can glide through the air like a bird but is Characteristics used to classify invertebrates include the water like amphibians. covered in fur. to which class does it belong? why? presence of a shell or hard cover, tentacles or spiny skin. a find out how a seal’s young are born. 4 what are the main characteristics of mammals? Organisms with similar features are placed in the same b given that the seal has long whiskers, to which 5 a describe how a baby echidna is born and develops group. The dichotomous tabular key in Figure 2.49 can class of vertebrate do seals belong? before it comes out of the mother’s pouch. be used to place an organism in a particular phylum. 2 a dolphin lives in the ocean and has fi ns. to which class b draw a puggle. does it belong? explain. ➔ Fig 2.49 Tabular key for identifying invertebrates.

Body spongy, with many holes Poriferan 1 Invertebrates Body not spongy Go to 2 Soft body, no shell Go to 3 There are many more invertebrates on the Earth than 2 vertebrates: 96% of all animals are invertebrates. Outside shell or hard cover Go to 6 Invertebrates have either an external skeleton Many tentacles or arms Go to 4 (exoskeleton) or no skeleton at all. The giant squid 3 (see Fig. 2.37 on page 68), huge as it is, has no Long body without tentacles Go to 5 backbone. As well as enormous animals like this, Tentacles around the mouth of a sac-like body Cnidarian thousands of tiny insects and other creatures belong 4 to the invertebrates group. Arms with suction discs Mollusc Invertebrates are classifi ed into six main groups or Mollusc Soft body, large foot phyla (see Fig 2.48). 5 Nematode, platyhelminth Worm-like or leaf-like Poriferans Cnidarians or annelid ➔ Fig 2.48 Some commonly found invertebrate phyla. • Spongy body with holes • Soft, hollow body Proper shell or smooth, hard covering Go to 7 6 • Found in water, attached • Live in water Spiny skin with rough covering Echinoderm to rocks • Tentacles

Examples: coral, Limbs in pairs Arthropod Examples: breadcrumb 7 sponge, glass sponges sea jelly, anemone Shell, no segments, large foot Mollusc

Molluscs Nematodes, platyhelminthes and annelids • Soft body • Soft, long body • Usually have a • Can be segmented, fl at protective shell or round

Examples: snail, Examples: leech, tapeworm, octopus, oyster, slug fl atworm

Echinoderms

• Rough, spiny skin Arthropods • Arms radiate from • Segmented bodies centre of body • Paired and jointed legs SAMPLE • Found in sea • Exoskeleton Examples: sea urchin, Examples: insect, spider, sea cucumber, brittle centipede, scorpion star

74 chapter 2 • sorting oUt biodiversity Unit 2.3 • where do i fit in? 75 practivity 2.6 The changing face of science

➔ a Scientists are still testing and modifying the Linnaean Identifying invertebrates ➔ b classifi cation system after 250 years. The development of microscopes led to the discovery of single-celled what you need: magnifying glass or stereomicroscope, organisms (bacteria). This led to the number of petri dishes, jars with lids, tweezers, vinyl or latex gloves, newspaper kingdoms increasing from three (plants, animals and minerals) to the current fi ve (Plantae, Animalia, Fungi, note: alternatively, your teacher may provide prepared Protista and Monera). In the 1970s, a group of organisms samples for you to look at. complete this classifi cation previously thought to be bacteria was discovered to exercise for each prepared sample. be something else: single-celled organisms that could live in extreme conditions, such as very salty or hot • do not touch any animal that might bite or sting. ➔ c waters. This led to the suggestion that a sixth kingdom, ➔ d check with your teacher if you are unsure. Archaea, was needed. Scientists are currently testing • Use tweezers to pick up animals. this idea and comparing it to a whole new system that ➔ a • place any animal immediately in a jar and put on comes before kingdoms. ➔ b the lid. The ‘three domain system’ was fi rst suggested in 1990. ➔ Fig 2.50 (a) Biologists collecting Archaea samples in the hot springs of the Obsidian This system suggests one super domain, Eukaryota, for Pool in the Yellowstone National Park, United 1 visit a local natural environment (e.g. a garden, the plants, animals, protists and fungi. The single-celled States. (b) A magnifi ed view of a clump of Archaean organisms. beach, park or pond) and observe invertebrate organisms in Kingdom Monera would then be split into specimens. two domains according to their genetic material. ➔ e 2 wearing gloves, use tweezers to collect up to ten The comparison of genetic material may cause even Museums currently hold most ‘holotype’ specimens, the invertebrate specimens in separate jars. greater changes to the classifi cation system in the future. organism(s) used when the description for classifi cation was decided. This specimen is chosen because it represents 3 Use the tabular key in figure 2.49 to classify the ➔ f Species that were previously thought to be related invertebrates into their particular phylum. because they looked similar are now found to have the majority of organisms of the same type. Museums are 4 Use a magnifying glass or stereomicroscope to help very different genetic material. That is the very nature likely to continue to do this, but most will need to put their you sketch each animal. put in the common name of science—to change and develop as new evidence data online into the future. for the animal (if you can) and write its classifi cation becomes available. This is why scientists collaborate group under the drawing. and share ideas, to make sure we have the 5 return the invertebrates to their natural environment best possible explanation for every scientifi c What do you know about the after you have fi nished. discovery. ➔ g changing face of science? The Internet allows more • Use the tabular key in figure 2.49 to identify sophisticated ways of 1 a ‘three kingdom’ system became fi ve and then the phylum of each of the invertebrates shown. organising, storing and six kingdoms. communicating scientifi c a what are the names of these kingdoms? information. Massive online b do you agree with the changes? explain. databases are possible, ➔ h complete with photographs 2 how has an understanding of genetics changed classifi cation? and even video of organisms. Links to related information 3 what is a holotype specimen? What do you know about invertebrates? can also be included and many 4 why do you think scientists might choose a scientists are using the Internet to single organism to represent its species, instead confi rm their identifi cations. of trying to fi nd a description that fi ts every 1 what percentage of animals are vertebrates? 4 eighty per cent of animals on the earth are arthropods. single organism in the species? 2 what is an exoskeleton? give an example of three a which characteristic does their name refer to? 5 what problems would a paper system for organisms with an exoskeleton. (hint: ‘arthritis’ and ‘podiatrist’) classifi cation encounter? how is this being b draw three different arthropods and label the addressed today? 3 beetles have segmented bodies and jointed legs. SAMPLE➔ Fig 2.51 Holotype specimens such as features that make them part of this phylum. to which phylum do they belong? this one are held in museums. 5 in practivity 2.6, which phylum of invertebrates did you fi nd in the greatest quantity? can you explain why?

76 chapter 2 • sorting oUt biodiversity Unit 2.3 • where do i fit in? 77 <> Diversity >>ZOOMING OUT<< Research

2.3 Where do I fit in? Choose one of the following topics to A trip to the Kimberley Research fascinating present a report in a format of your You have just returned from a trip organisms own choice. Some ideas have been to a remote mountain area of the Choose a fascinating organism included to get you started. Your Kimberley, in Western Australia. to research from each kingdom. report must include a key of some While there, you took your portable As you do your research, create a Remember and understand Analyse and evaluate description (you have seen many in microscope and examined water table using the following headings 1 What is the difference between vertebrates 11 Figure 2.49 on page 75 shows a dichotomous this chapter). from a previously unknown lake. To for each organism: ‘Habitat’, ‘Diet’, and invertebrates? Write a definition for each. key in tabular form for invertebrates. Construct A newspaper article your surprise you found some new ‘Classification’ and ‘Special features’. 2 List the five main classes of vertebrate and a branched dichotomous key for invertebrates. creatures in the water that looked a Write a newspaper article about how Choose one of the graphic organisers give an example of each. 12 Use a Venn diagram to show the similarities bit like bacteria. They are single-celled life on the Earth is organised. It needs used in this chapter to display the 3 Who developed the naming system used by and differences between birds, reptiles and and are either square or oval; some to be about two pages long (no more information about each one. scientists today? amphibians. are hairy (have hairs either on the than 500 words) and you should 13 Why is it important that scientists keep end of the cell or along the edge 4 List at least six phyla of invertebrates and give explain how living things are classified reviewing and evaluating the systems they use of the whole cell). an example of each. for an audience that is not familiar for classifying and naming living organisms, 5 Living things are classified into ______k , with science. Make a list of the living 1 Draw six different versions of and modifying them if necessary? What Review p______, ______, ______, things whose photographs you would these organisms. problems might arise if scientists were not ______, ______, ______. like to use to illustrate the article. Try 2 Create a dichotomous key for able to modify the systems that were originally Key words to find their scientific names as well as these six new organisms so 6 What is the difference between an endoskeleton developed? and an exoskeleton? their common names. Your newspaper that you can describe them to amoeba invertebrate article must contain a key of some autotroph key 7 What does a placental mammal look like Critical and creative thinking other scientists. description. bacteria kingdom when it is born? How does this differ from 3 Name each of the groups at 14 Using a digital camera, take photographs of binomial name Linnaean monotremes and marsupials? the bottom of your key (you animals around your house—from very big to biodiversity taxonomy might like to name some of 8 Why do scientists need to classify very small. Make a multimedia presentation botanist living them after yourself). living things? of your animals. Use a separate slide for each branched key microbiologist animal. On each slide include: 4 Assuming they are a type of cell multicellular Apply • the photograph bacteria, to which kingdom will cell wall mycologist they belong? 9 The vertebrates have five classes: Mammalia, • the common name and scientific name classification non-living Reptilia, Amphibia, Aves and Pisces. What are (if you can find it) dead nucleus the more common names for these classes? dichotomous key organism • the phylum and class 10 Fill in the table shown. DNA plankton • three or more interesting facts about ectotherm species Animal Vertebrate/invertebrate Class the animal. endoskeleton taxonomist endotherm taxonomy Octopus Reflect exoskeleton unicellular Spider <> genus vertebrate heterotroph Human Diversity Me My world Crab 15 ‘Scientific ideas are dynamic and 1 What new graphic organisers have 4 What was the most surprising Elephant developing—they are not just a collection you learned to use? animal you discovered? Frog of unchanging facts.’ 2 How could dichotomous keys 5 What else would you like to find My future Write a paragraph about how our be useful in other subjects? out about classification? Lizard 8 What Australian animals are knowledge of life on the Earth has changed Give examples. 6 What else would you like to find Snail SAMPLE unique in the world? How are over time to bring us to the understanding 3 What were the most difficult out about animals? we going to protect them in we have today. You might have the aspects of this topic? 7 Why is it important to organise the future? opportunity to read it to your class. life on the Earth?

78 Chapter 2 • sorting out biodiversity Chapter 2 • sorting out biodiversity 79 <> Diversity

active it lays in the sun, but when it is too hot outside it hides in a burrow until the How is life on Earth organised? heat has passed. 2 One fascinating thing that the thorny devil can do is drink water with its feet! It places its feet in a puddle and water moves up by capillary action along grooves in its skin to the corner of its mouth. Mammals are rarely seen during the day in Uluru–Kata Tjuta National Park. Most are nocturnal and come out in the evening, avoiding the heat of the daytime desert. The most abundant groups of mammals are the placentals (see Fig. 2.42 on page 70) and ➔ Fig 2.53 Puti habitat. the marsupials. Marsupials, such as the bilby, give birth to underdeveloped young but protect them by having 7 one of the classes of vertebrate is amphibia. what a pouch where further development can occur. The characteristic of amphibians would make it diffi cult for pouch is similar to that of a kangaroo; however, it is them to live in arid environments? what other animal a backward-opening pouch. When the young are fully classes would struggle to survive in arid environments? developed they can leave the pouch and survive the 8 why do you think the bilby’s pouch is rear-facing? harsh climate. 9 discuss why monotremes would fi nd it diffi cult to breed in arid environments. o 1 follow the link on the obook to fi nd out about the follow the link on the to investigate which kind of environment that the anangu lived in and o 10 obook mammals can be found in australia’s arid environments. foods they ate to survive. list at least fi ve animals classify each of these mammals as placentals, and fi ve plants that they ate. monotremes or marsupials. list any specifi c latin double 2 the early explorers left this environment because they ➔ Fig 2.52 Puli habitat. names given for each animal (genus and species). couldn’t survive. why did they struggle to fi nd food here? 3 in a group of four, use a large sheet of Have you ever visited Uluru or Kata Tjuta (the Olgas)? family groups and surviving by hunting wildlife and paper to create two collages on the one This area is part of Australia’s arid zone, a region gathering food from the land. sheet, one showing living things and one that receives less than 250 millimetres of rainfall per The Anangu knew where to fi nd food to survive and, showing non-living things you would expect year. Australia is the second driest continent in the more importantly, which areas were the best for hunting to fi nd in Uluru–Kata tjuta national park. world. Despite the harsh climate, this area is home to and gathering. The Anangu classifi ed their environment one pair creates the ‘living’ collage and the hundreds of different organisms. to help them locate the precious food. They used these other pair creates the ‘non-living’ collage. When early European explorers fi rst visited this names: 4 why do you think the anangu devised region in the 1870s they were confronted with a harsh Puli—rocky areas, gorges, stony slopes. Animals a system of classifi cation for the natural landscape. Their initial aim was to fi nd a route for the come to this area to fi nd shelter and water. habitats around them? overland telegraph line from Adelaide to the Top End Puti—open woodland. After the rains this area has 5 find out what ‘capillary action’ (in relation and to set up pastures for sheep and cattle grazing. an abundance of grass, which the kangaroos eat. Honey to water) means. They soon decided that the region was unsuitable, ants build their nests in this area. o 6 follow the link on the obook to investigate and left. Pila—spinifex plains, low areas between dunes. the mammals, reptiles, birds and However, the traditional owners of the land, This is the best place to gather seeds to eat. invertebrates found in the Uluru–Kata tjuta SAMPLEnational park. Make a list of fi ve for each a group of Anangu Aboriginal people, had lived on Reptiles are particularly suited to this environment. this land for thousands of years and understood it The thorny devil, like all reptiles, uses the environment category. classify each one into its correct well. They lived a nomadic life, travelling in small to regulate its temperature. When it wants to become group. ➔ Fig 2.54 Pila habitat.

80 Chapter 2 • sorting out biodiversity Chapter 2 • sorting out biodiversity 81