UNITUNIT I I ChapterChapter 1 1

TheThe Living Living World World Chapter Outline Chapter Outline 1.1. Diversity in the Living world 1.2.1.1. Need Diversity for Classification in the Living world 1.3.1.2. Taxonomy Need for and Classification Systematics 1.4.1.3. Three Taxonomy Domains and of Systematicslife 1.5.1.4. Taxonomic Three Domains Hierarchy of life 1.6.1.5. Nomenclature Taxonomic Hierarchy “Our task must be to…embrace all living 1.7.1.6. Concept Nomenclature of Species “Our task must be to…embrace creatures and theall whole living of creatures nature and and its the beauty.” whole 1.8.1.7. Tools Concept for study of Species of Taxonomy of nature— Albertand its Einstein beauty.” 1.8. Tools for study of taxonomy — Albert Einstein

Learning Objectives: have to depend on plants and animals for food. Animals are also used as source • Learns the importance of labour, in farming, as pets, and for of the living world and other economic benefits. Understanding its diversity animals and their unique characteristics, • Understands the need habitats, behaviour and evolutionary for classification relationships is very important. This • Creates an interest in systematics chapter deals with, diversity in the living and understands the importance world, need for classification, types of of taxonomy for classification of classification, taxonomical hierarchy, animals nomenclature and tools for studying • Knows the key rules of nomenclatures taxonomy. and their uses 1.1 Diversity in the Living All living forms co-exist with each other. There are about 8.7 million species of World animals which have been identified, Earth has numerous habitats with a wide named, described and classified. A study range of living organisms inhabiting reports that 86% of all species on the land them. Plants and animals are present in and 91% of those in the seas are yet to be almost all of the places, from polar ice discovered, described and catalogued. caps to volcanic hot springs, from shallow Though humans are placed in the top lagoons to the deepest oceans, from most position on the hierarchy, they tropical rain forests to dry and parched

1 A new estimate of biodiversity on Earth (2017)

1% 0.4% 0.1% 4.1% 2.8% 7.3% 5.6% 7.4% 78% 0.02% 17.6% 90.5% 7.3%

4.9%

73.1

Wilson (1992) Mora et al (2011) Wilson (1992) Mora et al (2011)Brenden Brenden et et al al (2017) (2017) A traditional estimate of the An estimate based on An estimate based on the relative richness of diff erent groups of projected richness of diff erent projected richness of organisms based on numbers of groups of organisms. diff erent groups of organisms. described species.

AnimalsFungi Plants Protists Bacteria

Newly Discovered Species Th reatened Species in India (2016) in India

Platyhelminthes Crustaceas

Amphibians Reptiles 1% 13% 2% Fishes Invertebrates

13% 31%

Insects

40%

Vertebrates Mammal Birds Reptiles Amphibian

Fishes Invertebrates

New Species Discovered in India (2016) Of the new animal species discovered in India, 258 are invertebrates and 55 vertebrates. As many as 97 species According to IUCN, 172 species of animals are considered of insects, 27 of fi shes, 12 species of amphibians, 10 of globally threatened in India or 2.9% of the world’s total Platyhelminthes, 9 of Crustacea and 6 of reptiles have been number of threatened species. discovered and described by scientists. Th ere are 61 species Th ese include 53 species of mammals, 69 birds, 23 reptiles of moths and butterfl ies (order Lepidoptera) and 38 of beetles and 3 amphibians, 2 fi shes and 22 invertebrates. (Coleoptera).

2 deserts. There are a variety of species waste lot of time in finding an item. In that have been adapted successfully to the same way, libraries also organize the live in diverse ecosystems. Ecosystem is books alphabetically or genres-wise into a community of living organisms (plants autobiographies, novels, kids stories, and animals), non-living environment science fictions, etc. Likewise it is nearly (including minerals, climate, soil, water, impossible to study all the living organism sunlight) and their interrelationships hence it becomes necessary to device some (A.G. Tansley, 1935). The presence of a means and methods to make this possible large number of species in a particular and this process is called classification. ecosystem is called ‘biological diversity’ Classification is a process by which things or in short ‘biodiversity’. The term are grouped in convenient categories, biodiversity was first introduced by based on easily observable characters. The Walter Rosen (1985), and defined by E.D. scientific term used for these categories Wilson. is taxa (taxon–singular). Taxa indicates categories at different levels, for example Difference between the Living and Kingdom Animalia, includes multicellular Non-living animals such as reptiles, mammals, etc. Living organisms show a variety Based on their characteristics, all living of unique characters different organisms can be classified into different from non-living matter. The key taxa. This science of classification is characters of living organisms are, called taxonomy. External and internal cellular organization, nutrition, structures along with developmental respiration, metabolism, growth, response processes and ecological information to stimuli, movement, reproduction, of organisms are essential, as they excretion, adaptation and homeostasis. form basis of the taxonomical studies. Numerous scientists and taxonomists Hence, characterisation, identification, have made tremendous contribution and nomenclature and classification are the documentation in the observation and scientific stages that are basic to taxonomy. study of even minute characters in living The basic need for classifications are: organisms. Their keen observations have • To identify and differentiate closely led to the classification of living organisms related species and the study of their interrelationships. • To know the variation among the 1.2. Need for classification species • To understand the evolution of the We come across many places where species things are arranged in specific categories. • To create a phylogenetic tree In super markets, the shelves can have rows and columns of groceries, cosmetics, among the different groups toys, stationeries, snacks and utensils. • To conveniently study living If it is not arranged in a well organized organisms manner, customers and sales persons will

3 1.3 Taxonomy and the organisms. Apart from the above Systematics said features, evolutionary history of the species and the environmental adaptations Taxonomy (G. taxis- arrangement ; nomos- and interrelationship between species are law) is the science of arrangement of also being investigated in systematics. living organisms along with classification, description, identification, and naming History of Classification of organisms which includes all flora and Early classification of organisms were fauna including microorganisms of the based on only two criteria, beneficial or world. The word taxonomy was coined by harmful animals. An ancient classification Augustin Pyramus de Candole (1813). system recognized 5 animal groups - Taxonomy is a theoretical study of domestic, wild, creeping, flying and classification with well defined principles, sea animals. Initially the classification rules and procedures. Aristotle is called was based on organism’s fundamental the father of taxonomy (classical) and characteristics such as the habitat and Carolus Linnaeus is the father of modern morphology only. taxonomy. Aristotle (384 to 322 BC), was the first to classify all animals in his History of System Systematics (G. /sequence) Animals (Historia Animalium in Latin). The objectives of taxonomy and He attempted a basic classification of all systematics are very similar; their goal living organisms into Plants and Animals. is to classify organisms with stipulated Animals were classified based on rules. The main criteria of systematics locomotion; walking (terrestrial), flying is identifying, describing, naming, (aerial) and swimming (aquatic). Based arranging, preserving and documenting on the presence or absence of red blood he classified the animals into two as Enaima with blood and those without blood as Carolus Linnaeus is Anaima. the father of modern Aristotle’s classification system had taxonomy, which is limitations and many organisms were not the system of classifying and fitting into his classification. For example, naming organisms. One of the tadpoles of frogs are born in water and his contributions was the have gills but when they metamorphosed development of a hierarchical into adult frogs they have lungs and can live system of classification of nature. both in water and on land. How to classify Today, this system includes frogs and where to place them? Aristotle eight taxa: domain, classified organisms based on locomotion, kingdom, phylum, hence, birds, bats, and flying insects were class, order, family, grouped together just by observing one genus, and species. single characteristic feature, the flying ability. On the contrary to the above said

4 example, the ostrich, emu and penguin organisms. A modification of this system are all birds but cannot fly. So Aristotle is the numerical taxonomy, which evolved would not have classified them as birds. in the 1950s. This system evaluates the In spite of these limitations Aristotle’s resemblances and differences through classification system was followed for statistical methods followed by computer more than 2000 years upto 1700. analyses to establish the numerical degree After Aristotle, his student of relationship among individuals. Later Theophrastus (372-287 BC) continued on biologists initiated studies on the his research on the classification of evolutionary and genetic relationships plants, and he was known as the “Father among organisms, which led to the emerge of of Botany.” There was a huge gap till phylogenetic classification or cladistics. 16th century, then the English naturalist It is an evolutionary classification based John Ray (1627–1705) wrote several on how a common ancestry was shared. important works through his life. His Cladistic classification summarizes the most important contribution was the genetic differences between all species establishment of species as the ultimate in the ‘phylogenetic tree’. Ernst Haeckal unit of taxonomy. In 1682 he published introduced the method of representing the Methodus Plantarum Nova, which evolutionary relationships with the help contained about 18,000 plant species, of a tree diagram known as cladogram. a result of a relatively narrow species This system of classification takes concept. His complicated classification into account ancestral characters (traits was based on many combined characters, of basic body design which would be in as opposed to earlier taxonomists. John the entire group) and derived characters Ray also aimed at publishing a complete (traits whose structure and functions system of nature, which included works differs from those of ancestral characters). on mammals, reptiles, birds, fishes and One or more derived characters which insects. The Swedish biologist Carolus appeared during evolution resulted Linnaeus (1707 - 1788) father of modern in the formation of new subspecies. taxonomy and founder of modern In a cladogram each evolutionary systematics developed a scientific system step produces a branching and all the of taxonomy and binomial nomenclature, which is still (with modifications) in use. Figure 1.1. Example of a Cladogram Aristotle to Linnaeus employed easily observable single to few traits for classification of organisms. With 5D\5D\)LQQHG  )LQQHG 5RGHQWV 6KDUNV ILVK $PSKLELDQV &URFRGLOHV %LUGV UDEELWV 3ULPDWHV increased knowledge of the several biological domains, many characters were +DLU considered for classifying organisms. (JJVZLWKVKHOOV This represented the phase of classical $PQLRWLFHJJ taxonomy which was based on overall )RXUOLPEV %RQ\VNHOHWRQ similarities or affinities derived from 9HUWHEUDH morphology, anatomy and embryology of

5 members of the branch would possess the 1.4. Three Domains of life derived character which will not be seen Three domain classification was proposed in organisms below the particular branch by Carl Woese (1977) and his co- workers. point. Arranging organisms on the basis They classified organisms based on the of their similar or derived characters difference in 16S rRNA genes. The three which differ from the ancestral characters domain system adds the taxon ‘domain’ produced a phylogenetic tree or cladogram higher than the kingdom. This system (Figure 1.1). emphasizes the separation of Prokaryotes Depending on the system of into two domains, Bacteria and Arachaea, classification, organisms were classified and all the eukaryotes are placed into the into two or three kingdoms. Later into four, domain Eukarya. Archaea appears to have five, six and now into seven kingdoms. more in common with the Eukarya than R.H.Whittaker (1969) proposed the Five the Bacteria. Archaea differ from bacteria kingdom Classification, the Kingdoms in cell wall composition and differs from defined by him were Monera, Protista, bacteria and eukaryotes in membrane Fungi, Plantae, and Animalia based on composition and rRNA types. the cell structure, mode of nutrition, mode of reproduction and phylogenetic relationships. Table 1. gives a comparative account of different characteristics of the Thermus aquatics is a five kingdoms. bacterium which can Classification has come a long way and tolerate high temperatures. now takes into an account even molecular The first DNA polymerase enzyme was level DNA and RNA identification. The isolated from T. aquaticus it is advancement in molecular techniques used in PCR (Polymerase Chain and biochemical assays has led to a new Reaction ) for DNA amplification. classification - The “Three Domain” classification.

THREE DOMAINS (Carl Woese, 1977)

ARCHAEA BACTERIA EUKARYA (Extremophiles) Cyanobacteria & (Eukaryotes) Methanogens, Halophiles, Eubacteria, beneficial& Protista, Fungi, Plants Thermoacidophiles pathogenic and Animals

6 1. Domain Archaea are photosynthetic blue green algae which Th is domain includes single celled produce oxygen. Th ese had played a key role organisms, the prokaryotes which have the in the changes of atmospheric oxygen levels ability to grow in extreme conditions like from anaerobic to aerobic during the early volcano vents, hot springs and polar ice geologic periods. caps, hence are also called extremophiles. Th ey are capable of synthesizing their food Curd is one of the best sources without sunlight and oxygen by utilizing of probiotics, which are friendly hydrogen sulphide and other chemicals bacteria that can improve our health. from the volcanic vents. Some of the them e.g. Lactobacillus sp. produced methane (methanogens), few live in salty environments (Halophiles) and are 3. Domain Eukarya (Eukaryotes) thermoacidophiles which thrive in acidic Eukaryotes are animals which have true environments and at high temperatures. nucleus and membrane bound organelles. 2. Domain Bacteria DNA in the nucleus is arranged as a linear chromosome with histone proteins, Bacteria are prokaryotic, their cells have no ribsosomes of 80S type in the cytosol and 70S defi nite nucleus and DNA exists as a circular type in the chloroplast and mitochondria. chromosomes and do not have histones Animals in this domain are classifi ed under associated with it. Th ey do not possess kingdoms, namely, Protista, Fungi, Plantae membrane bound organelles except for and Animalia. ribosome (70S type). Th eir cell wall contains peptidoglycans. Many are decomposers, In 1987, Cavalier-Smith revised the some are photo-synthesizers and few cause six kingdom system to Seven Kingdom diseases. Th ere are benefi cial probiotic system. Th e concept of super kingdom was bacteria and harmful pathogenic bacteria introduced and revised to seven kingdom which are diversely populated. Cyanobacteria classifi cation. Th e classifi cation is divided

FIVE KINGDOM CLASSIFICATION KINDS OF KINGDOM Salient features Monera Protista Fungi Plantae Animalia Cell type Prokaryotic Eukaryotic Eukaryotic Eukaryotic Eukaryotic Cell wall Non-cellular Present in Present Present Absent some Body Cellular Cellular Multicelluar Tissue Tissue organisation Tissue Organ Organ Organ system Mode of Autotrophic Autotrophic Heterotrophic Autotrophic Heterotrophic nutrition Heterotrophic Heterotrophic

Table 1. Five Kingdom Classifi cation

7 into two Super Kingdoms (Prokaryota and Archaebacteria) and five Eukaryotic and Eukaryota) and seven kingdoms, Kingdoms (Protozoa, Chromista, Fungi, two Prokaryotic Kingdoms (Eubacteria Plantae and Animalia).

The Three-Domain System

Bacteria Archaea Eukarya

The traditional Five – Kingdom system

Monera Protista Fungi Plantae Animalia

The Six –Kingdom system

Bacteria Archaea Protista Fungi Plantae Animalia

The Seven – Kingdom system Archae- Eubacteria Protozoa Chromista Fungi Plantae Animalia bacteria

1.5. Taxonomic hierarchy In biological classification, the taxonomical intermediate categories such as subkingdom, hierarchy includes seven major categories grade, division, subdivision, subphylum, namely kingdom, phylum, class, order, superclass, subclass, superorder, suborder, family, genus and species and other superfamily, subfamily and subspecies.

Hinny Mule

Liger Tigon Figure 1.2 Sterile offsprings 8

Family: It is a taxonomic category Biological nomenclature which includes a group of related genera derives from the binomial (or with less similarity as compared to genus binominal) nomenclature and species. For example, the family that was originally codified in the Felidae includes the genus Felis (cats) works of Linnaeus, Species Plantarum and the genus Panthera (lions, tigers, (1753) and Systema Naturae, 10th leopards). Edition (1758). These publications Order: This category includes an are the starting points for the modern assemblage of one or more related families biological nomenclature in most groups which show few common features. One of plants and animals. or more similar families are grouped together to form an order. For example, family Canidae and Felidae are placed in Phylum: The group of classes with the order Carnivora. similar distinctive characteristics Class: This category includes one or constitute a phylum. The classes Pisces, more related orders with some common Amphibia, Reptilia, Aves and Mammalia characters. For example order Primata constitute the next higher category, comprising monkeys, apes and man is phylum Chordata. These classes share placed in the Class Mammalia, along with some common features like presence of the order Carnivora which includes dogs a notochord and a dorsal tubular nerve and cats. cord hence included in the phylum Recently Discovered Chordata. species in South India Kingdom: All living Scientists have discovered a animals belonging to new and unusual species of frog in the various phyla are included Western Ghats in India in August 2017. in the Kingdom Animalia The frog has shiny, purple skin, a light and it is the top most of blue ring around its eyes, and a pointy the taxonomic hierarchy. pig-nose. It is named as Bhupathy’s purple frog (Nasikabatrachus bhupathi) to honour Dr.Subramaniam Bhupathy, In July, 2017, a 9 years herpetologist who lost his life in the old boy discovered a new Western Ghats in 2014. Freshwater species of Jellyfish in the Kodaikanal lake, Tamilnadu.

1.6. Nomenclature Giza, Inimene, Emberi, Manna, Doanna, Umano ……. In all probability these words must be new to you…but they all mean “Human”

10 in different foreign languages! There are of the International Code of Zoological presently more than 6000 languages in Nomenclature (ICZN). The scientific the world and an animal can be named name ensures that each organism has only in more than 6000 ways! Unfortunately one name. it is impossible for anyone to have a good functioning knowledge of most languages Binomial Nomenclature and hence there arises a need for a (L. Bi-two; Nomen-Name) universally accepted scientific naming Biologists follow universally accepted system for all organisms. The process of principles to provide scientific names assigning scientific names to animals or to known organisms. Each name has taxonomic group is called nomenclature. two components, a generic name and a For example, worldwide, the scientific specific epithet. This system of naming name Homo sapiens denotes human. the organism is called Binomial Classification and grouping were done to Nomenclature which was popularised facilitate a deeper understanding of the by Carolus Linnaeus and practised by unique characteristics of each organism biologists all over the world. Example, and its interrelationship among closely the National Bird (Indian Peafowl) – related species. It plays a vital role in Pavo cristatus, the National Animal tiger the arrangement of known species based as Panthera tigris, and the Tamil Nadu on their similarities and dissimilarities. State bird is the common Emerald dove Numerous characters such as morphology, Chalcophaps indica. genetic information, habitat, feeding pattern, adaptations, evolution, etc., are Trinominal Nomenclature examined before an organism is named. (Tri – three) One of the primary responsibilities of systematic biology is the development This naming system was proposed by of biological nomenclature and Huxley and Stricklandt, Trinomen means, classification. Nomenclature is not an three names: generic name, species name end to systematics and taxonomy but it is and sub-species name. When members of necessary in organizing information about any species which have large variations biodiversity. Nomenclature, functions then trinomial system is used. On the to provide names for all taxa at all levels basis of dissimilarities, this species in the hierarchy of life. Naming of the gets classified into subspecies. It is the organisms is done based on the guidelines If you find an animal with four legs, with two eyes, paired ear pinna, A newly discovered Himalayan covered with fur, possessing forest thrush bird was named mammary gland , which class will after the birdman of India, you position it? How will you give Ornithologist Dr. Salim Ali. a binomial name, if you are the first The name of the bird is“ Zoothera salimalii”. person to discover and report that A fruit bat is also named after him “Latidens salimalii” animal.

11 extension of binominal nomenclature discovered and named after Scientist system which has an addition of Varad Giri, Cyrtodactylus varadgirii. subspecies. All the three names are set in italics and only the generic name is 1.7. Concept of species capitalized, if handwritten then it should Species is the basic unit be underlined separately E.g.Corvus of classification. The splendens splendens (Indian house crow) term species was coined Tautonymy: The practice of naming the by John Ray, and in his animals in which the generic name and book “Historia Generalis species name are the same, is called Plantarum” (3 volumes) Tautonymy. e.g. Naja naja (The Indian in 1693 described species as a group of Cobra). morphologically similar organisms arising from a common ancestor. Carolus Linnaeus What may be the reasons for the in his book “Systema naturae” considered extinction of Dinosaurs? If you know species as the basic unit of classification. the reasons for their extinction, why Species can be defined as a group of Sparrows are listed as endangered organisms that have similar morphology and species? physiology and can interbreed to produce fertile offsprings. In 1859 Charles Darwin Rules of Nomenclature in his book Origin of species explains the • The scientific name should be italicized evolutionary connection of species by the in printed form and if handwritten, it process of natural selection. should be underlined separately. • The generic name’s (Genus) first 1.8 Tools for study of alphabet should be in uppercase. taxonomy • The specific name (species) should be Tools and taxonomical aids may be different in lowercase. for the study of plants and animals. • The scientific names of any two Herbarium and Botanical garden may be organisms are not similar. used as tools for the study of plant taxonomy. In the case of animal studies, the classical • The name or abbreviated name of tools are Museum, Taxonomical Keys and the scientist who first publishes the Zoological and Marine parks. scientific name may be written after the species name along with the year of publication. For example Lion-Felis leo Arignar Anna Zoological Park, also known Linn., 1758 or Felis leo L., 1758. as the Vandalur Zoo is in the south western • If the species name is framed after any part of Chennai, Tamil Nadu, spreads over person’s name the name of the species an area of 1500 acres, is one of the largest shall end with i, ii or ae. zoological parks in India. The zoo houses For example, a new species of a ground- 2,553 species of both flora and fauna. dwelling lizard (Cyrtodactylus) has been 12 The important components of the of DNA sequences), DNA fingerprinting taxonomical tools are field visits, survey, (to identify an individual from a sample identification, classification, preservation and of DNA by looking at unique patterns in documentation. Many tools are being used for their DNA), Restriction Fragment Length taxonomical studies, amongst them some of Polymorphisms (RFLP) analysis (difference the important tools are discussed below: in homologous DNA sequences that can be detected by the presence of fragments The classical taxonomical tools of different lengths after digestion of the Taxonomical Keys: Keys are based on DNA samples), and Polymerase Chain comparative analysis of the similarities Reaction (PCR) sequencing ( to amplify a and dissimilarities of organisms. There specific gene, or portion of gene,) are used are separate keys for different taxonomic as taxonomical tools. categories. Museum: Biological museums have Automated species identification tools collection of preserved plants and animals It consists of Cyber tools. For example: for study and ready reference. Specimens DAISY, ALIS, ABIS, SPIDA, Draw wing, etc. of both extinct and living organisms can be ALIS o Automated Leafhopper studied. Identification System. Zoological parks: These are places DAISY o Digital Automated where wild animals are kept in protected Identification System. environments under human care. It enables ABIS o Automatic Bee Identification us to study their food habits and behaviour. System. Marine parks: Marine organisms are SPIDA oSpecies Identified Automatically maintained in protected enviroments. (spiders, wasp and bee wing characters). Printed taxonomical tools consist of Draw wing o Honey bee wing identification cards, description, field guides identification. and manuals. Neo taxonomical tools – This is based on Electron Microscopy images to study the Molecular taxonomical tools molecular structures of cell organelles. Technological advancement has helped Ethology of taxonomical tools – Based to evolve molecular taxonomical tools on the behaviour of the organisms it can from classical tools to molecular tools. The be classified. For example sound of birds, accuracy and authenticity is more significant bioluminescence, etc. in the molecular tools. The following e-Taxonomic resources – INOTAXA methods are being used for taxonomical is an electronic resource for digital images classification. and description about the species which Molecular techniques and approaches was developed by Natural History Museum, such as DNA barcoding (short genetic London. INOTAXA means In tegrated marker in an organism’s DNA to identify Open TAXonomic Access. it as belonging to a particular species), DNA hybridization (measures the degree of genetic similarity between pools 13 Activity ______The main objective of this activity is to check the students understanding about animals and its characteristics before learning the lesson. Observe the picture given below, identify the animals and classify them according to you own understanding; write one character about each class of animals. Take the students to the school ground and ask them to observe and identify few invertebrates (insects, earthworm, spiders etc). Ask the students to write few characteristics of each animal which they have observed.

Sl.No Name of the Animal Known Character Class Habitat 1 2 3 4 14 ICT Corner

Deep Tree

Let’s do this activity to know the position of a particular species in the Evolution path.

Step – 1 Type the URL in the browser. Click ‘Play Game’ button then use your personal or school id to login. Otherwise use Guest Pass to enter. Then click the DEEP TREE icon that is given below The Evolution Lab to start the activity. Step – 2 Input the common name of any animal in the SEARCH tab given at the bottom of the activity window, select the appropriate Zoological name from the list appeared. Step – 3 7KH&ODVVL¿FDWLRQDQGWKHSODFHRIWKHVSHFLHVLQWKHDQLPDO.LQJGRPFDQEHYLHZHGE\ clicking the Icon placed next to the search tab. Step – 4 7ZRGL൵HUHQWVSHFLHVFDQEHFRPSDUHGE\FOLFNLQJRQWKH5(/$7(EXWWRQJLYHQDW the bottom of the activity window. The relation between those species can be learnt by clicking the DNA icon appeared.

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15 Summary Earth has numerous habitats with a wide The taxonomical hierarchy includes seven range of living organisms inhabiting it. categories namely kingdom, phylum, class, Living organisms show a variety of unique order, family, genus and species. The process characters different from non-living matter. of assigning scientific names to animal or Classification is the process by which taxonomic group is called nomenclature. Each anything is grouped in a convenient category scientific name has two components, generic based on some easily observable characters. name and a specific epithet. The important Taxonomy is the science of arrangement of component of the taxonomical tools are field living organisms. R. H. Whittaker proposed visits, survey, identification, classification, the five kingdom classification. Three preservation and documentation. Molecular domain classification was proposed by Carl taxonomical tools are more accurate, authentic Woese and his co-workers. and significant for taxonimical classification.

Glossary Shared character – A shared character is one that two lineages have in common Cladogram – A branching diagram show- ing the relationship between a number of Derived character – Derived character is species. one that evolved in the lineage leading up to a clade. Phylogeny – Relationships among vari- ous biological species based upon simi- Threatened species – Species which are larities and differences in their physical vulnerable to endangerment in the near or genetic characteristics. future. Phylogenetic tree – A phylogenetic tree or evolutionary tree is a branching dia- gram or "tree" showing the inferred evo- lutionary relationships upon similarities and differences in their physical or genet- ic characteristics.

Evaluation 1. A living organism is differentiated from 2. A group of organisms having similar non-living structure based on traits of a rank is a. Reproduction a. Species b. Growth b. Taxon c. Metabolism c. Genus d. Movement d. Family

16 3. Every unit of classification regardless of 8. Molecular taxonomic tool consists of its rank is a. DNA and RNA a. Taxon b. Mitochondria and Endocplamic b. Variety reticulum c. Species c. Cell wall and Membrane proteins d. Strain d. All the above 4. Which of the following is not present in 9. Differentiate between probiotics and same rank? pathogenic bacteria a. Primata 10. Why mule is sterile in nature? b. Orthoptera 11. List any five salient features of the c. Diptera family Felidae d. Insecta 12. What is the role of Charles Darwin in 5. What taxonomic aid gives comprehensive relation to concept of species? information about a taxon? 13. Why elephants and other wild animals a. Taxonomic Key are entering into human living area? b. Herbarium 14. What is the difference between a Zoo c. Flora and wild life sanctuary? d. Monograph 15. Can we use recent molecular tools to 6. Who coined the term biodiversity? identify and classify organisms? a. Walter Rosen 16. Explain the role of Latin and Greek b. AG Tansley names in Biology. c. Aristotle d. AP de Candole 7. Cladogram considers the following characters a. Physiological and Biochemical b. Evolutionary and Phylogenetic c. Taxonimic and systematic d. None of the above

References 1. Peter H. Raven, George B. Johnson, Holt Rinehart & Winston Harcourt Susan R. Singer, Jonathan B. Losos Education Company. (2004) Biology 7th Edition Published 3. Peter H. Raven, George B. Johnson, by McGraw-Hill Science. Kenneth A. Mason, Jonathan B. Losos, 2. Janet L. Hopson and John Postlethwait Susan R. Singer (2013) Biology 9th Edition. (2006) Modern Biology Published by Published by McGraw-Hill Science.

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