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Home , Acanthocephala, Bryozoa, Chaetognatha, Chordate, Ctenophora, Gnetophyta

The of by Dana Visalli/www.methownaturalist.com

It is not known how life on earth began. Genetic and chemical evidence indicates that life was initiat- ed only once, as one , and that all succeeding organisms are descendants of this first life, which is known as LUCA--the last universal common ancestor. The Earth is thought to be 4.5 billion old, and life appeared approximately 3.8 billion years ago, almost as soon as the planet had stabilized ade- quately for life to be theoretically possible. Estimates for the total number of species alive today vary wildly, from around 5 million to more than 100 million. 1.8 million species have been named and catego- rized by scientists. The immediate evolutionary relationships among organisms are not universally agreed upon and so the branching of the has different interpretations. The one used here is one of the more straightforward versions. Life began as relatively simple, single cells resembling , and diversified from there into 6 distinct Kingdoms: Bacteria, Archea, , , Fungi and . A currently popular alternate tree divides life first into 3 domains--Bacteria, Archea, and (see below), and then the Eukaryotes radiated into 4 kingdoms. An important evolutionary is between prokaryotes and eukaryotes. The word prokaryote translates from the Greek as ‘before the ,’ or ‘before the nucleus.’ Prokaryotes--Bacteria and Archea- -do not have a nucleus in their cells--a separate area with its own membrane that contains the DNA of the . The word means ‘true seed’ or ‘true nucleus,’ and obviously a eukaryote does have a nu- cleus. This group includes the other 4 kingdoms of life besides Bacteria and Archea: Protists, Plants, Fun- gi and Animals. Primary Life Groups: 6 Kingdoms: Bacteria (Greek, ‘cane,’ because the first Bacteria discovered were rod-shaped)- About 2000 species known in 11 phyla. The total number is hard to assess, guesses range from the tens of thousands to billions. Bacteria are prokaryotes; their cells have no nucleus. They are found in almost all environments, from deep underground to the stratosphere. The of bacteria thought to exceed that of all animals and

plants combined. Bacterial cells are about 1/10th the size of eukaryotic cells and Bacteria, magnified 1000x are typically 0.5-5.0 u (micrometers; a micrometer is 1 millionth of a meter) in length.

Dana Visalli/[email protected]/www.methownaturalist.com, Kingdom Archea (Greek, ‘ancient’)- About 1000 species known in 2 phyla; the actual total existing is unknown. Like Bacteria, Archea are prokaryotes, but they have unique proper- ties that separate them from both eukaryotes and Bacteria. Most Archea are an- aerobes--they obtain their energy without using oxygen, and in fact oxygen is toxic to them. Many Archea are ‘extremeophiles,’ which means ‘lover of extreme conditions.’ They can be found thriving in extremely hot water (up to and above An Archea, Sulfolobus 212°F), in ice, in super-saturated salt water. and deep below ground. Size is 0.1-15 u.

Kingdom Protista (Greek, ‘the very first’) (aka Protoctista)- 100,000-200,000 species in 36 phyla. Pro- tists have eukaryotic cells and are mostly unicellular; some are multicellular but have no specialized tissue, for example. They are typically divided into 3 groups, -like, -like and fungi-like protists. Size is variable; while aver- aging 0.1 mm, they vary from 0.01 mm to 65 meters (giant ). Paramecium, a Kingdom Plantae (Latin, ‘to sprout’)- About 300,000 species in 12 phyla (often called divisions in the Plant Kingdom). Plants are thought to have evolved from certain . They began to colonize land 450 million years ago, which required some means of dealing the problem desiccation (drying out). Size ranges from the duckweed-like Wolffia which is 0.5 mm long, to the largest redwood tree at 115 meters (380 feet) tall.

Kingdom Fungi Flower anthers & (Greek ‘’)- 75,000 species in 6 phyla have been identified; total may num- ber more than a million. One of the 6 phyla of Fungi is , which are mostly fungal with an algae or symbiont ( inside the ). Fungi are now thought to have diverged from other life 1.5 billion years ago, and colo- nized land about 500 million years ago. Most plant species have a symbiotic (beneficial) relationship with one or more fungal species. The majority of the fun- gi that we see----have most of their organic structure underground and can grow to enormous size. A honey (Armillaria ostoyae) in Ore- Honey mushroom gon grows over 2200 acres and is a contender for the largest organism on the plan- et. Yeast cells can be as small as 2 micrometers (2 millionths of a meter).

Kingdom Animalia (Latin, ‘breath’ or ‘soul’)- The total number of animals on earth is unknown; a mil- have been identified and the total is probably well over 5 million (including insects and various phyla). 99% of all animals are --they lack a backbone. Of the 36 phyla of animals, most are aquatic of one sort or an- other. Truly land-dwelling forms are found only in two phyla, Arthropoda A piglet, in moss (insects and their kin) and Cordata (animals with backbones). One contender for the smallest animal in the world is the water or moss piglet (); di- minutive ones are 0.1 mm long. The largest animal in the world and the largest that has ever lived is the blue . It can grow to 100 feet in length and 400,000 pounds. Before there were probably a million blue in the ; today there are about 8000.

Kingdoms break down as follows: Subkingdom, , , , , Ge- A nus, Species. For example are in Phylum Chordata, Class Mammalia, Order , Family , , Species H. sapiens.

2 Branches on the Tree of Life

Prions (The name derived from ‘-infection’)-A is an infectious agent, a pro- tein in a misfolded form. All known prion diseases in affect the struc- ture of the or other neural tissue and all are currently untreatable and fatal. Diseases include bovine spongiform encephalapathy (mad cow disease) and Creutzfeldt-Jacob Disease. Prions are not considered living organisms but are mis- folded protein molecules which may propagate by transmitting a misfolded pro- tein state. If a prion enters a healthy organism, it induces existing, properly White spots are microscopic holes folded to convert into the disease-associated, misfolded prion form. This in neural tissue caused by prions triggers a chain reaction that produces large amounts of the prion form. Prion rep- lication is subject to just like in living organisms.

Viruses (Latin, ‘poison’)- About 5000 viruses are known, with another 4000 unclassified, and probably over million extant. A virus is a minute infectious agent that can reproduce only by entering a cell in a living organism and using its cell ma- chinery. Some can crystallize like minerals and persist for years in that state. Vi- ruses can infect all types of life forms, from animals and plants to Bacteria and Archea. The smallest ones are only 20 nm (nanometers, 20 billionths of a meter, 20 millionths of a millimeter). Viruses attacking a bacteria The virus particle, or virion, in its simplest form is just nucleic acid enclosed in a protein shell. Its may consist of double- or single-stranded DNA or RNA. the smallest viruses have as few as four , while the largest have several hundred. Much smaller still are viroids, tiny molecules of naked RNA, which foul up the metabolism of plants.

Prokaryotes (Greek, ‘before the seed’) Prokaryotes are organisms that have what could be considered primitive cells which have no nucleus--no membrane-bound area inside the cell containing the cell’s DNA. A second type of larger cells, the eukaryotes (‘true seed’), do have a nucleus. Two kingdoms make up the prokaryotes, Bacteria and Archea. They are the earliest life form we know of, 3.8 billion years old, and the only life-form on Earth for 2 billion years. Prokaryotes outnumber all eukaryotes combined: there are more bacteria in one than all the people that have ever lived; the human body contains more bacterial cells than human cells, and it is thought that the biomass of Bacteria and Archea outweigh the combined biomass of the other 4 kingdoms. They are pervasive, being found in salty, acidic, alkaline, and very hot and cold environments as well as what life typically considers comfortable.

Bacteria are essential to the other kingdoms, as decomposers of organic material, fixers of nitrogen, and pro- ducers of atmospheric oxygen and nitrogen. If Bacteria disappeared, the other four kingdoms would soon fol- low. On the other hand half of all human disease is caused by Bacteria. Some are opportunistic- they are always present, for example Streptoccus pneumonia, which is always in the , and will multiply when body defenses are down.

Prokaryotes are 1/10 to 1/100 the size of eukaryotic cells, have 1/1000 the DNA, and are haploid, which means they only have one strand of DNA, rather than two (diploid). Bacterial motility (movement) is by flagella or slime . Reproduce occurs by binary --splitting in half--which progresses geometri- cally. Some cells can reproduce every 20 minutes, which would equal 1 million kg in 24 hrs. Like sex in eu- karyotes, prokaryotes do indulge in bacterial conjugation, when two organisms come into contact, a thin bridge can form, through which one of the bacteria donates a copy of some of its DNA. Many prokaryotes can also pluck short strands of DNA out of the surrounding liquid medium, where it has been ejected by oth- er cells.

3 Kingdom Bacteria - Although known primarily as soil bacteria, they may be more abundant in freshwaters. Actinobacteria is one of the dominant bacterial phyla and contains one of the largest of bacterial genera, Streptomyces. While many cause diseases in humans, Streptomyces is a notable source of antibiotics. Al- though some of the largest and most complex bacterial cells belong to the Acti- nobacteria, the group of marine bacteria in this phylum has been described as possessing some of the smallest free-living cells. Streptomyces Aphragmabacteria- These are tiny, irregularly-lobed, ameba-like cells that live as intracellular parasites of many different animals, plants, and protists. As such, they are the smallest cellular organisms on earth with a range in size of 0.3-0.5 µm (micrometer, a thousandth of a millimeter). Several Aphragmabacteria diseases af- flict humankind. One is Mycoplasma pneumoniae, the causative agent of a disease of the upper and lower respi- ratory tracts. Bacteroides- Obligate anaerobes (cannot co-exist with oxygen). Bacteroides are normally mutualistic, making up the most substantial portion of the mammalian gastrointestinal flora, where they play a fundamental role in processing of complex molecules to simpler ones in the host intestine. As many as 1010-1011 (100 billion) cells per gram of human have been reported. Studies indicate that long-term diet is strongly associated with the gut microbiome composition. Those who eat plenty of protein and animal fats have predominantly Bacteroides bacteria, while for those who consume more carbohydrates the Prevotella species dominate Chlorobia- A strictly anaerobic (‘without oxygen’), photolithotrophic (‘rock-living’) us- ing hydrogen sulfide as an source (and sometimes hydrogen gas, and water) and CO2 as a carbon source. Chlorobium species are thought to have played an important part in mass events on Earth. If the oceans turn anoxic (due to the shutdown of circulation) then Chlorobium would be able to out-com- pete other photosynthetic life. They would produce huge quantities of methane and hydrogen sulfide which would cause global warming and acid rain. This would have huge consequences for other oceanic organisms and also for terrestrial organisms. Evidence for abundant Chlorobium populations is provided by chemical fos- sils found in sediments deposited at the mass extinction. Chloroflexa- Another strictly anaerobic, photolithotrophic green sulfur bacteria recently split out of Chloro- bia (above), found in hot springs. Cyanobacteria (cyano is Greek for ‘blue’)- Aerobic (‘with oxygen’) photosynthe- sizers. By producing gaseous oxygen as a byproduct of , cyanobac- teria are thought to have converted the early reducing (negatively charged) atmosphere into an oxidizing one (positively charged, hungry for electrons, which are negative.....and are readily available from hydrogen atoms), which dra- matically changed the composition of life-forms on Earth by stimulating biodiver- sity and leading to the near-extinction of oxygen-intolerant organisms. According Cyanobacteria to endosymbiotic theory, the found in plants and eukaryotic algae evolved from cyanobacterial ancestors via endosymbiosis....which is to say, chloroplasts were once individual, free-living bacteria, which were engulfed by a larger bacteria, probably with an intention to consume, but in- stead of being consumed began to work together with and inside of the larger cell (= ‘working to- gether). Deinococci (from the Greek, ‘dreadful granule’)- Aerobic bacteria that are highly resistant to environmental hazards. Deinococcus survive when their DNA is ex- posed to high doses of gamma and UV radiation. Where other bacteria change their structure in the presence of radiation, such as endospores, Deinococcus toler- ate it without changing their cellular form and do not retreat into a hardened structure. A human lethal dose of radiation is 500 rads, Deinococcus has tolerated

3 million rads. Found in hot springs. Deinococcus

4 Pirellulae- Obligate aerobes found in . Species in this phylum cause a number of diseases, includ- ing chlamydia and pneumonia.

Proteobacteria- Purple bacteria- Because of the great diversity of forms found in this group, the Proteobacte- ria are named after Proteus, a Greek god of the capable of assuming many different shapes. They include a wide variety of , such as Escherichia, Salmonella, Vibrio, Helicobacter, and Yersinia, and many other notable genera. Others are free-living (nonparasitic), and include many of the bacteria responsible for nitro- gen fixation.

Spirochaetae- A group of chemoheterotrophs (they feed on energy bound up in compounds) with helically coiled (corkscrew shaped) cells. Most are free-living and anaerobic, but there are numerous exceptions. Found in marine and fresh water, muddy sediments, and the gastrointestinal tracts of some mammals.

Thermotogae (Greek ‘heat’ and ‘toga’-some species have an extra sheath)- anaerobic, mostly thermophilic (heat loving) and hyperthermophilic bacteria found around deep sea vents and hot springs.

Kingdom Archea It was realized only as recently as the 1970s that as organisms have unique properties separating them from both Bacteria and all of the eukaryotes. Archea are similar in size and shape to Bacteria, but contain genes and chemical pathways that are more closely related to eukaryotes than to Bacteria. Most are ‘extremophiles,’ living in extreme environments: hot, cold, salty, dark, although they have also been found in benign environments, like in the human navel.

Archea (Greek, ‘spring old quality’)- Thermoacidophiles, Crenarchaeota inhabit hot springs all over the world, and also may be abundant in deep in rocks. They are that assimilate CO2 into their bodies using inorganic chemicals as energy sources: H2, CH4, NH3, and other re- duced (hydrogen rich) compounds.

Euryarchaeota (Greek, ‘true ancient ones’)- Methanogens and halophiles (salt-loving)- some are motile via flagella and some are immotile. All 3 classic bacterial shapes-- rods, spirillum and coccus-- are represented. Methanogens are found worldwide in sewage, sediments, and in the intestinal tracts of animals, including wood-eating insects. They have names prefixed by ‘methano.’ Methanogens obtain energy by reducing CO2 and oxidizing H2, forming methane. Halophiles live in extremely salty or alkaline environments.

Kingdom Protista (Greek ‘very first to establish’)- The protists are generally speaking the smallest of the organisms with eukary- otic cells--that is, cells with a nuclear membrane (forming the nucleus) inside the larger cell membrane. Most protists are single-celled organisms. The kingdom as a whole is a catch-all unit that has in other schemes been divided up in to as many as 20 kingdoms. Used here is one of the most basic and easily understood taxono- mies for this group. The 16 phyla listed are divided into 5 informal groups based on mobility and nutrition:

Group 1- with no permanent means of locomotion (3 phyla):

Actinopoda (Greek, ‘ray feet’)- Actinopods and radiolarians are non-motile, het- erotrophic Protista with a diameter of 0.1–2 mm that produce intricate mineral made of silica. They are found as throughout the ocean, and their skeletal remains make up a large part of the ocean floor as siliceous ooze. Radiolarians have many needle-like pseudopodia (‘false feet’) which aid in the Radiolarian's buoyancy. Radiolarians can often contain symbiotic algae which provide most of the cell's energy. The earliest known date to the very A Radiolarian start of the period 550 million years ago. Radiolaria appear to be most abundant in warm waters of the equatorial zone, unlike which prefer cool water. They can also act as predators, capturing diatoms and other organisms by ingesting them into their central cavity.

5 (Latin, ‘little hole bearing’)- There are about 9000 known species. Foramins are amoeboid protists, characterized by streaming protoplasm that among other things is used for for catching food, and by an by an external shell, or test, usually made of . All but a few are aquatic and most are marine, the majority of which live on or within the seafloor sediment () while a smaller variety are floaters in the water column at various depths (). A few are known from freshwater or brackish conditions and some soil A foraminfera test (shell) species have been identified. Foraminifera typically produce a shell which can have either one or multiple chambers, some becoming quite elaborate in structure. They are usually less than 1 mm in size, but some are much larger, the largest species reaching up to 20 cm.

Rhizopoda (Greek, ‘root foot’)- the single-celled . They are characterized by the possession of pseudopodia--temporary outgrowths of the , which are used for locomotion and engulfing food particles. Rhizopods are found in fresh- water and marine habitats and the soil. Amoebas reproduce by binary fission; there is no . Amoeboid-like cells occur not only among the , but also fungi, algae and animals.

Group 2- Photosynthetic Protists (7 phyla)

Bacillariophyta (Latin, ‘little stick plant’)- Diatoms (Greek, ‘to cut through,’ refer- ring to the 2 halves of the ’s shell) are a major group of algae, and are among the most common types of . Most diatoms are unicellular, although they can exist as colonies in the shape of filaments or ribbons, fans, zigzags, or stars. Diatom-Cymbella affinis Diatoms are major producers within the marine and freshwater food chains. A unique feature of diatom cells is that they are enclosed within a cell wall made of silica. They are especially important in oceans, where they are estimated to contrib- ute up to 45% of the total oceanic , and are responsible for 25% of the oxygen in the atmosphere.

Chlorophyta (Greek, ‘yellow-green plant’)- These are the green algae. They have traits in common with the plants (like plants they utilized chlorophylls ‘a’ and ‘b’, and store energy as starch) and are in fact sometimes placed in the Plant Kingdom. Green algae may be unicellular (one cell), multicellular (many cells working togeth- Volvox aureas er), colonial (living as a loose aggregation of cells) or coenocytic (composed of one large cell without cross-walls). While most species live in freshwater habitats and a large number in marine habitats, other species are adapted to a wide range of envi- ronments. Watermelon snow, or Chlamydomonas nivalis, lives on summer alpine snowfields. Others live attached to rocks or woody parts of . Some lichens are symbiotic relationships between fungi and green algae. Life was simple when all green-colored algae were included in a single phylum. Increasingly, it has become clear that the green algae are very diverse in their relationships and are now often included in two phyla, (4500 species) and (3500 species). Synura- a Chrysophyta Chrysophyta (Greek, ‘golden plant’)- A phylum of unicellular marine and freshwa- ter protists known as the golden algae, this includes the abundant and sometimes the diatoms (Bacillariophyta). Some are free-swimming individuals and others are colonial; the vast majority are photosynthetic. As such, they are par- ticularly important in lakes, where they may be the primary source of food for zoo- plankton. They are not considered truly autotrophic by some biologists because nearly all chrysophytes become facultatively heterotrophic (‘other-feeding’) in the absence of adequate light, or in the presence of plentiful dissolved food. When this occurs, the photosynthetic cell atrophies and the alga may turn predator, feeding on bacteria or diatoms. There are more than 1000 described species. Coccolith- 6 Dinoflagellata- (Greek, ‘whirling whip’)- A large group of flagellated (tailed) pro- tists. Most are marine plankton, but they are common in freshwater habitats as well. Many are photosynthetic, but some are known to be mixotrophic, combining photosynthesis with ingestion of prey. In terms of number of species, dinoflagel- form one of the largest groups of marine eukaryotes, although this group is substantially smaller than the diatoms. Some species are of marine animals and play an important part in the biology of reefs. About 1600 spe- Dinoflagella cies are described, with an estimate of 2600 total extant. So-called red tides are caused by .

Euglenophyta- Euglenids are commonly found in freshwater, especially when it is rich in organic materials, with a few marine, and endosymbiotic members. Most euglenids are unicellular. Many euglenids have chloro- plasts and produce energy through photosynthesis, but others feed by phagocytosis (‘to devour a cell’) or strictly by diffusion. Prey such as bacteria and smaller are ingested through the cell mouth (the cy- tosome).

Phaeophyta (Greek, ‘dusky brown plant’)- Brown Algae, a large group of mostly marine multicellular algae, including many of colder Northern Hemisphere waters. They play an important role in marine en- vironments, both as food and for the habitats they form. For instance Macrocystis, a brown , may reach 60 meters in length, and forms prominent underwater forests. Worldwide there are 1500–2000 species.

Rhodophyta (Greek, ‘red plant’)- , about 6000 species of mostly multicellular algae, primarily ma- rine but including 164 freshwater species. Many of the coralline algae, which secrete calcium carbonate and play a major role in building coral reefs, belong here.

Group 3- Heterotrophs with flagella or cilia (2 phyla)

Ciliophora (Latin, ‘eyelash bearing’)- The are a group of protists character- ized by the presence of hair-like organelles called cilia, which propel the organism via an undulating movement. Ciliates are an important group of protists, common almost everywhere there is water: in lakes, ponds, oceans, rivers, and soils. About 3,500 species have been described, and the potential number of extant species is estimated at 30,000. Included in this number are many ectosymbiotic and endo- symbiotic species, as well as some obligate and opportunistic parasites. spe- Didinium injesting a Paramecium cies range in size from as little as 10 µm to as much as 4 mm in length, and include some of the most morphologically complex protists. Most ciliates are heterotrophs, feeding on smaller - isms, such as bacteria and algae, and detritus swept into the oral groove (mouth) by modified oral cilia.

Zoomastigophra (Greek, ‘animal whip’)- These are free living or parasitic, sexual or asexual heteroptrophs with at least one ; some have thousands of them. Some species are parasitic, such as Typanosoma, a zooflagellate causing African Sleeping Sickness. The protist disease agents are acquired from human beings or from animals harboring the parasites.

Group 4- Non-motile -forming animal parasites (1 phylum)

Apicomplexa (Latin, ‘summit enfolding’) (aka Archeaprotista)- is a large group of parasitic protists, most of which possess a unique organelle, a type of called an apicoplast, and an apical structure involved in penetrating a host's cell. They are unicellular, spore-forming, and exclusively parasites of - mals. Flagella are found only in the motile . Includes Plasmodium, the cause of malaria, which kills up to 200 million people per , and Giardia lamblia, the causative agent of giardia. Giardia lamblia

7 Group 5- Slime Molds-heterotrophs with restricted mobility

Acrasiomycota (Greek, ‘bad judgement fungus’) (aka Rhizopoda)- Cellular slime molds; they occur in damp habitats on land and feed on microorganisms. When food runs out and they are ready to form sporangia, they release signal molecules into their environment, by which they find each other and create swarms. These amoeba then join up into a tiny multicellular slug-like coordinated creature, which crawls to an open lit place and grows into a fruiting body, a sporangium. Some of the amoebae become to begin the next generation, but some of the amoebae Cellular Slime Mold sacrifice themselves to become a dead stalk, lifting the spores up into the air.

Myxomycota (Greek, ‘ fungus’)- Plasmodial slime molds share one big cell wall that surrounds thousands or millions of nuclei. Proteins called microfilaments act like tiny muscles that enable the mass to crawl at rates of about 1/25th of an inch per hour. As long as there is enough food and moisture, the mass thrives. But when food and water are scarce, the mass separates into smaller blobs. The Plasmo- dium forms stalks topped by sphere-like fruiting bodies that contain spores that are carried by the rain or wind to new locations. Plasmodial Slime Mold

Oomycota (Greek, ‘ fungus’)- filamentous protists which must absorb their food from the surrounding water or soil, or may invade the body of another organism to feed. As such, play an important role in the decomposition and recycling of decaying matter. Parasitic species have caused much human suffering through destruction of crops and . ‘Egg fungus’ and refers to the large round oogonia, or structures con- taining the female . The Oomycota were once classified as fungi, because of their filamentous growth, and because they feed on decaying matter like fungi. The cell wall of oomycetes, however, is not composed of , as in the fungi, but is made up of a mix of cellulosic compounds. Some water molds are parasites on other organisms; they may grow on the scales or of fish, or on . Other species are parasitic on aquatic invertebrates such as , , and , and on diatoms.

Kingdom Fungi (From Greek, ‘sponge’)- There are an estimated 100,000 species. Fungi differ from other organisms in having cell walls that contain chitin; genetic studies have shown that fungi are more closely related to animals than to plants. Nearly all fungi can reproduce asexually by releasing spores produced by a single parent. Many are also capable of sexual reproduction by conjugation of tissue. For many, sexual reproduction is a contingency mode that occurs only when there has been an unfavorable change in the environment. The few unicellular fungi, like yeast, are thought to have evolved from multicellular forms. Mycelium (the underground portion of the organism) can grow up to half a mile a day. The oldest fungi date to the , 410 million years ago. These are intimately associated with fossil plant tissue. It has been suggested that fungal as- sociations made it possible for plants to become truly terrestrial. Today terrestrial ecosystems would collapse without fungi to decompose dead organic matter. 8 genera in this classification:

Ascomycota (Greek, ‘bladder fungus’)- About 64,000 species known. The sac-fungi produce spores in small cup-shaped sacs called asci, hence the name . The mature sac fungi spores are known as ascospores, they are released at the tip of the ascus breaks open. Yeast is the most common one-celled ascomycete. Yeast re- produces through asexual process called . The buds form at the side of the parent cell, they pinch-off and grow into new yeast cell which is identical to the par- ent cell. Examples of sac-fungi are morels, truffles, cup fungi and powdery mil- Morels are Ascomycetes dews.

Basidiomycota (Greek, ‘club fungus’)- About 32,000 species known. includes the classsic mush- rooms, puffballs, smuts, and rusts. The spores are borne on a club-shaped spore case called basidium. The ba-

8 sidia are lined up on the under the cap. An average sized mushroom produces over 16 billion spores. These spores rarely germinate or mature.

Blastocladiomycota- These small fungi live in fresh water and soil. Some are para- sites on nematodes, midges, and plants, including one that causes ‘brown disease’ on corn, and another that parasitizes alfalfa. Amanitas are Basidiomycetes (Greek, ‘little cooking pot fungus’)- Chytrids are one of the early diverging fungal lineages and are saprobic, degrading refractory materials such as chitin and , or acting as parasites. Their mem- bership in kingdom Fungi is demonstrated by their chitin cell walls and absorptive (saphrophitic) nutrition. About 800 species have been identified. Chytrids have been isolated from a variety of aquatic habitats, includ- ing peats, bogs, rivers, ponds, springs, and ditches, and terrestrial habitats, such as acidic soils, alkaline soils, temperate forest soils, rainforest soils, arctic and Antarctic soils. The chytrid species Batrachochytrium dendroba- tidis is responsible for chytridiomycosis, a disease of amphibians. Discovered in 1998, this disease is known to kill amphibians in large numbers, and has been suggested as a principal cause for the worldwide decline.

Glomeromycota- Approximately 230 described species. Most species are terrestrial and widely distributed in soils worldwide where they form symbioses (mycorrhizas) with the roots of the majority of plant species (>80%).

Lichenes (Lichenales)- A is a composite organism that emerges from algae or cyanobacteria (or both) living among filaments of a fungus in a mutually benefi- cial relationship. The whole combined has properties that are very different from properties of its component organisms. The fungus benefits from the symbiotic rela- tionship because algae or cyanobacteria produce food used by the fungus by photo- synthesis. There are about 20,000 known species of lichens. Xanthoria- a crustose lichen Micosporidia- The constitute a phylum of spore-forming unicellular parasites. They were once thought to be protists but are now known to be fungi. Loosely 1500 of the probably more than one million spe- cies are named. Microsporidia are restricted to animal hosts, and all major groups of animals host microspo- ridia. Most infect insects, but they are also responsible for common diseases of crustaceans and fish.

Zygomycota- These fungi are usually found on cheese, bread, and other decaying food. They are zygote forming fungi, hence the name . The spores are produced in round-shaped case called sporangium. The grayish fuzz seen on bread and decaying food is actually mass of mature sporangia mold. Under the micro- scope they are seen as pinheads. When the sporangium breaks open hundreds of spores are released. About 700 species are known. Zygomycota Kingdom Animalia (Latin ‘having breath’)- All animals are heterotrophs (‘other-eating’) and must ingest other organisms or their products for sustenance. Most animal phyla appeared in the fossil record as marine species during the Cam- brian explosion 540 million years ago. The earliest known animal fossils are found in 665-million-year-old rock in Australia. They are distinguished from plants, algae and fungi by lacking rigid cell walls and digest- ing food in an internal chamber. All animals are motile, if only at certain life stages.

Subkingdom Parazoa (Greek, ‘beside animals’): lack tissues organized into organs and have an indetermi- nate shape.

9 1. (Greek, ‘flat animal’): These are considered ‘ animals,’ representa- tives of early of the Animal Kingdom. They are the simplest in structure of all non-parasitic animals. They are generally classified as a single species, adhaerens, although there is enough genetic diversity that it is likely that there are multiple, morphologically similar species. They were first discovered in 1883, in a saltwater in Austria. Barely visible to the naked at about 1 mm across, they are amoeba-like, with no regular body outline. It feeds on small particles of A Placozoan, probably Trichoplax organic debris. It’s evolutionary history is not clear and it is considered possible they lost physiological complexity rather than never having had it.

2. Porifera (Latin, ‘pore bearing’): 10,000 species, most marine with only 150 species in freshwater. These are the ‘,’ multicellular organisms that have bodies full of pores and channels allowing water to circulate through them. Sponges do not have nervous, digestive or circulatory systems. Instead most rely on maintaining a constant water flow through their bodies to obtain food and oxygen and to remove wastes. They are filter feeders; it is estimated that a sponge must filter 1 ton of water to grow 1 ounce in weight. Most are ; is released into water Porifera and drawn into neighboring sponge. Sponges are similar to other animals in that they are multicellular, heterotrophic, lack cell walls and produce sperm cells. Unlike other animals, they lack true tissues and or- gans and have no body symmetry.

Subkingdom (Greek, ‘true large animals): Eumetazoa have tissues organized into organs. They are divided into two branches, (radial body symmetry) and Bilaterata (bilateral symmetry).

Radiata: 3. (pronounced nigh-dear-ee-ah, Greek, ‘nettle’) (aka ) (Greek, ‘hollow intestine’) >10,000 species, including hydras, , sea anenomes, and coral. They have one body opening, a gastrovascular cavity, with no distinct or- gans. There are two body plans, a sessile polyp (e.g. hydra) and a floating medu- sa (jellyfish). They are all , with a net but no brain; their behavior is rigid. No one has yet trained a jellyfish. Some jellyfish have are 30 me- ters long. Fossils exist to 700 million years age. Divided into 4 classes: Pacific Sea Nettle- Cnidaria 1. : Almost wholly sessile: sea anemones and coral animals. 6200 sp. 2. Cubozoa: Sea wasps and box jellies. A few genera. 3. Hydrozoa: Includes hydras and ‘colonial swimmers’ such as the Portugese Man o’ War; 3 100 sp. 4. Scyphozoa: jellyfish. 200 sp.

4. (Greek, ‘comb bearing’): Comb Jellies. About 150 species known. Body of soft gelatinous material in a membrane bag, with comb paddles, which are aggregates of external cilia. All are marine. They range in size from a few millime- ters to 1.5 meters in length. Like Cnidarians they have a decentralized rather than a brain; they are sometimes classified with Cnidarians in the now usual- ly defunct phylum Coelenterata. Ctenophores are predators, taking prey ranging from microscopic larvae and rotifers to the adults of small crustaceans. A Ctenophoran

Bilateral Symmetry Bilaterally symmetrical organisms may be acoelomate (Greek,‘without a hollow’--no cavity between gut and outer body wall), pseudocoelomate (cavity present, but not completely lined with ), or coelomate (having a true , a completely lined with mesoderm).

Acoelomate- no cavity between gut and outer body wall

10 5. Platyhelminthes (Greek, ‘flat worm’): 15,000 species. Relatively simple bilateral, unsegmented, soft-bodied invertebrates. Unlike other bilaterians, they are acoelo- mates (no body cavity), and have no specialized circulatory and respiratory organs, which restricts them to having flattened shapes that allow oxygen and nutrients to pass through their bodies by diffusion. The digestive cavity has only one opening for both ingestion and egesetion (removal of wastes). Found in freshwater, marine and humid terrestrial environments. Traditionally broken down into the 3 following A , Platyhelminthes groups, which have proven to not be monophyletic (do not share a close common ancestor): : parasitic tapeworms, living mostly on . No digestive system. Can grow to more than 20 meters. : parasitic flukes, mostly on vertebrates. There are 200 million people around the world who are infected w flukes (schistoma), suffering body pains, anemia and dysentery. : free-living . Simplest of all , the are acoelomate with one body opening, dis- tinct organs, and a rudimentary; they can modify response to stimuli.

6. (Greek, ‘thread-form’)- 350 species are known and 2000 are ex- pected. They are known as horsehair worms, so-called because they are hair-like and there was a belief they sprang from horsehairs. They range in size from 50-100 cm. They are found all over the world in all kinds of water, a few are found in soil. They have no respiratory, circulatory, excretory nor digestive organs, absorbing nu- trients through the cell walls. The adult worms are free-living, but the larvae are parasitic on arthropods such as and . Horsehair Worm 7. Nemertina (Greek, the name of a sea nymph)- About 900 species. ranging in size from 0.5 mm to one that measured 54 meters, making it the longest animal ever found. Know in the vernacular as worms, also called ribbon worms. The are free-living, mostly bottom-dwelling marine worms with a distinctive eversi- ble proboscis consisting of a long, hollow tube. Nemerteans move slowly, using their external cilia to glide on surfaces on a trail of slime. They are very similar to flatworms, but do have a digestive tube with two open- ings and simple . Pseudocoelomate-an incipient cavity between the gut and the outer body

8. Nematoda Greek, ‘thread’)- About 25,000 species described, an estimated 1 mil- lion in existence. Nematodes or roundworms, more than half are parasitic. Unlike cnidarians and flatworms, nematodes have tubular digestive systems with openings at both ends. They are present in nearly every ecosystem from marine to freshwater to to soils. They represent 90% of all animals on the ocean floor, and are so numer- ous that they may comprise 80% of all individual animals on earth. Humans host at least 50 species of nematodes. Nematodes are critical in the aeration of soil and the circulation of its mineral and organic components. 9. Rotifera (Latin, ‘wheel bearer’)- 2200 species have been described. Most rotifers are 0.1-0.5 mm long, and are common in freshwater environments throughout the world, with a few saltwater species. Some rotifers are free swimming and truly planktonic, others move by inchworming along a substrate, and some are sessile, attached to gelatinous holdfasts that are attached to a substrate. The are an impor- tant part of the freshwater zooplankton, being a major food source and with many species also contributing to the decomposition of soil organic matter. 10. (Greek, ‘thorn ’)- 1150 species have been described. A phylum of parasitic worms known as thorny-head worms, characterized by the presence of an eversible proboscis armed with spines, which it uses to pierce and hold the gut wall of its hosts, which may include invertebrates, , amphibians, and mammals. Recent genome analysis has shown they are descended from rotifers. Acanthocephala 11 11. (Greek, ‘to move the snout’) - 180 species known. A phylum of small (1 mm or less) that are widespread in mud aand sand at all depths; sometimes called mud dragons. They do not have external cilia, but in- stead have a number of spines along the body, plus up to 7 circles of spine around the head. These are used for locomotion, gripping the substrate with the spines while drawing up the body. They feed on organic matter in the substrate. Kinorhyncha 12. Annelida (Latin, ‘little ring’)- 10,000 species of worms, distinguished by the ringlike external segments that coincide with internal partitions containing digestive and reproductive organs repeated in tandem. They live in marine and freshwater and in soil, ranging in size from 0.5 mm to 3 meters (the giant Australian earth- worm). Included here are the former phyla (240 species of small marine worms), Pogonophora (deep- sea tube worms, 80 species) and ( worms, also marine, 300 species). There are 3 classes of An- nelids: Hirudinea: Leeches, 300 species. Leeches can suck up to 10 times their body weight of blood,then not eat again for 4 months. Oligochaeta: 3100 species. Terrestrial bristle worms, including earthworms. Polychaeta (‘many setae’ or bristles”) 5400 species. Marine bristle worms, featherduster worms, tubeworms.

13. (Greek, ‘claw bearers’)- 180 species. Popularly known as worms, these creatures have tiny , antennae, and multiple pairs of legs (between 13 and 43 pairs). Velvet worms grow to between 0.5 and 20 cm long. They have variously been compared to worms with legs, caterpillars and slugs. Most common in tropical regions of the Southern Hemisphere, they prey on smaller ani- mals such as insects, which they catch by squirting an adhesive mucus. In modern , they are particularly renowned for their curious mating behavior and for Onychophora bearing live young. Males of many Australian species exhibit special structures on the head, which apparently take over certain tasks in transferring sperm to the females. In the species Euperipatoides rowelli, sperm is collected by these structures, and, when a female is encountered, the worm inserts its head in the .

14. Tardigrada (Latin, ‘slow step’)- More than 1000 species. The common names for are ‘moss piglets’ (they are common among moss) and ‘water ’ (tardigrades have legs tipped with claws, and a lumbering gait). They are micro- scopic, water-dwelling, segmented animals with eight legs. Depending on the spe- cies, they range in size from 0.1 to 1.5 mm long. Tardigrades occur throughout the world in some of the most inhospitable places, from high peaks in the Himalayas (above 20,000 ft) to boiling water near heat vents on the ocean floor, and from the A Moss Piglet Arctic to vast ice fields of . During severe environmental conditions that would kill most creatures on earth, tardigrades roll up into little dehydrated balls called "tuns" where they survive for extend- ed periods of time. This dormancy phenomenon is called cryptobiosis (or anabiosis). They can survive temper- atures of -450° F to +300°F. A lethal dose of x-rays for humans is 500 roentgens; it is 600,000 roentgens for moss piglets. - 15. (Latin, ‘moss animal’)- 4150 species known. Aquatic filter feeders because they often look like plants. Typically about 0.5 mm long, they sieve food particles out of the water using a retractable crown of tentacles lined with cilia. Mostly marine, some live in freshwater. Some species form mineralized exoskele- tons that encrust over surfaces.

Coelomate: has a true body cavity completely lined with mesoderm. A Bryozoan

16. Brachiopoda (Latin, ‘arm foot’)- 300 species. Marine animals with bivalve shells that attach to rocks by a fleshy stalk.. They have the common name lamp shells, because some look like old pottery oil lamps. Brachio-

12 pods live mostly in cold water and low light. They can live up to 30 years; most ob- tain a width of only 10 to 30 mm. The ventral shell is is usually larger than the dorsal, and the body is aligned within differently than in mollusks (dorsally and ventrally rather than laterally).

17. (Latin, ‘soft’)- 150,000 species, including snails slugs, oysters, clams, oc- , and . Most are marine while some live in freshwater or are terrestrial. All A are soft-bodied, most are protected by a shell of calcium carbonate. Size ranges from 1 mm to 20 meters (giant ). North America has the largest number of freshwater mollusk species in the world. There are 5 com- mon classes (and 3 rare ones not listed here): 1. Cephalopoda (head foot’)- Octopi, squid and nautilus. They are built for speed, with well-developed . Shelled called ammonites were the domi- nant invertebrate predators for hundreds of millions of years until the mass extinc- tion at the end of the Cretaceous. Only one shelled survives, the chambered nautilus. 2. (‘ foot’)- snails and slugs, 100,000 species. The largest of all classes except Insecta (below). Chambered Nautilus 3. Pelecyoda (‘hatchet foot’)- Also known as Bivalva: clams, , scallops, oysters (15,000 species). 4. Polyplacophora- . They have oval bodies covered by eight scaly plates (650 species). 5. Scaphopoda- Tusk or shells.

18. (Greek, ‘hair ’)- About 125 species identified, commonly known as arrow worms. A phylum of predatory marine worms that are a major component of plankton worldwide. They are found in all marine waters, from shal- low tide pools to the deep sea and polar regions. Most chaetognaths are transparent and are shaped, but some deep-sea species are orange. They range in size from 2 mm to 12 cm. Despite the limited diversity of species, the number of individu- als is large. of Chaetognatha

19. Arthropoda (Greek, ‘jointed foot’). Probably 5 million species or many more; the total is unknown. As biol- ogist JBS Haldane famously remarked, ‘God has an inordinate fondness for beetles.’ Some taxonomies break up Arthropoda into -- & their kin, and Mandibulata-insects and crustaceans. Arthropods have jointed appendages and an made of chitin (a stiff and complex derivative of glucose). They have well-developed sense organs, extensive , and an open circulatory system (no arteries and veins). The , which evolved in the sea for protection, pre-adapted arthropods for life on land, as the chitin retains water. The oldest animal fossils found on land are 400 million year old . It is a complex phylum, with 3 (or more) subphyla) and 18 classes.

Subphylum Chelicerata (Greek, ‘arm lips’)- Spiders & Kin. 6 pair of appendages, of which the first pair differ from the others. Called chelicerae, they are jawlike and grasping. Chelicerata lack sensory antennae. 3 classes: 1. Class Arachnida: Spiders, scorpions, and ticks. All have 4 pair of segmented legs, most are carnivorous, most prey on insects. There are 10 or more orders, 8 are listed below. umping 1. Acarina- mites and ticks- 48,000 species. 2. Araneida-spiders- 38,000 named, may be twice as many extant. 3. Chelonethida- pseudoscorpions- 3300 species. 4. Hydrocarina-watermites- 5000 species. 5. Phalangida- daddy longlegs. 6. Scorpoionida- scorpions- 1300 species. 7. Solpugida- wind scorpions- 200 species. 8. Thelyphonida- whip scorpions- 100+ species. Whip Scorpion

13 2. Class Merostomata- Horseshoe crabs- 4 species. 3. Class Pycnogonida- Sea spiders- 1300 species.

Subphylum Crustacea (Latin, ‘skin’)- 68,000 species described, includes , co- pepods, isopods, barnacles, , crabs, . Crustaceans have 2 antennae and 2 body regions, the cephalothorax and the abdomen. There are 9 orders: 1. (‘both feet’)- scuds and beach hoppers. 2. Branchiopoda- fairy shrimp, shrimp, clam shrimp. 3. Cirripedia- barnacles. 4. Cladocera- water fleas. 5. Copepoda- . Among the most numerous of animals. 6. - lobster, crayfish, crabs, shrimp. 7. Isopoda (‘equal feet’)- 7 pair of equal leglike appendages. Mostly marine but includes sow & pill bugs. 8. Malacostraca- krill. 9. Ostracoda- seed shrimp.

Subphylum (or Uniramia)- Insects (Latin, ‘to cut into,’ referring to the dis- tinct body segments)- Millions of species in at least 26 orders. Insects have 3 pairs of legs, 3 body sections, 1 pair of antennae, and generally 1 or 2 pair of wings. In terms of insects outnumber all other forms of life combined. Common on land and in freshwater, they are rare in the sea. The fossil insects are from the Devo- nian, 410 million years ago. Insecta Subphylum - Centipedes and Millipedes. 14,000 species. Centipedes have 1 pair of legs per seg- ment and antennae with 14 segments; they are terrestrial carnivores. Millipedes have 2 pair of legs per seg- ment and antennae with 7 segments, they are vegetarian and detrivores. The Illacme plenipes has 750 legs.

20. Echinodermata (Greek, ‘ skin’)- 7000 species. , sea urchins, sand dollars, sea cucumbers, sea lilies. Adults have radial symmetry, but larvae are bilateral. There are no freshwater nor terrestrial spe- cies. They are characterized by the presence of , which serve for locomotion, food handling and respi- ration. Another distinct trait which most have is their remarkable powers of of tissue, organs, limbs, and in some cases complete regeneration from a single limb. Geologically they are im- portant in that their ossified skeletons are major contributors to many limestone formations.

21. Hemichordata (Greek, ‘half chord’)- 90 species, known as acorn worms. They are worm-like marine filter feeders from 2.5 to 250 cm long that inhabit U-shaped burrows in sandy or muddy substrate. They resemble in that they have slits and a nerve chord, and they are in fact the closest extant phylogenetic rele- tives of chordaes among the invertebrates.

22. Chordata (Latin, ‘chord’)- 65,000 species. All chordates share 3 distinct character- An istics: 1. A is present in all , 2. All chordates have dorsal, hollow nerve chord, 3. Pharyngeal slits (gill slits) are present on all embryos (these probably originally functioned as filters for filter feeding in early chordates). There are 3 subphyla: 1. Urochordata (Latin, ‘tail chord’)- 1260 species, these are the , including sea squirts, in which most adults are soft-bodied, sessile or planktonic marine filter- feeders that lack the definitive chordate features. However all larvae have the standard chordate features, including long, tadpole-like tails; they also have rudi- mentary brains. 2. Cephalocordata (Latin, ‘head chord’)- 25 species, known as or amphioxus. They are small marine animals with elongated bodies with a notochord that extends Tunicate

14 the length of the body. They spend much of their lives buried in sand in shallow wa- ter, filter-feeding on organic matter through their 100 pharyngeal slits. In some loca- tions they are extremely common; at Discovery Bay in Jamaica up to 5000 individuals can be found per square meter of sand. 3. Vertebrata- vertebrates with distinct 64,000 species, including fish, amphib- ians, , mammals, and birds (this subphylum is sometimes referred to Crania- A lancelet ta). Characteristics include 1. cephalization (a central brain and sensory structures, 2. a enclosing a nerve chord, 3. a closed circulatory system with a and veins, 4. paired appendages. Most species survive an average of 2 million years before going extinct. 7 existing classes and 2 extinct ones listed below.

1. Class (‘without jaws’): 6 species; lampreys, and slime . No true jaws, scales or fins. The vertebral column is cartilaginous. The young ammocoete is similar to the amphioxus, with more apparent cephalization, larger gill slits, mouth and segmented muscle. Included here are the extinct Ostracoderms (shell-skinned), the first well defined vertebrates. They were small jawless, bony, armored fish appearing in the , abundant in the -Devonian. Lamprey The hard 'shell' over the head was of calcium phosphate, the equivalent of bone. 2 orders: 1. Mxyiniformes: . 2. Petromyzontiformes: lampreys.

2. Class Placoderma (‘plate–skinned’): A long extinct group of armored fish with jaws, which replaced the os- tracoderms in the Devonian. Probable ancestors of the (bony fish). To 3 meters length.

3. Class Acanthodii: Appeared in the Devonian and now long-extinct, they were small (minnow-sized) predators with spine–supported fins, body scales, jaws with replacement teeth and an . They are in an evolutionary line with , both having homocercal tails. Extinct.

4. Class Chondrichthyes- , rays and chimera. 800 sp. Cartiligenous , true jaws and fins, no operculum, internal fertilization, egg with , auditory, sight and olfactory organs. Sharks have regions in their skin that can pick up electric fields generated by muscle contraction, as well as lateral lines. 5-7 external gill slits. The largest is the whale , to 60' and 40 tons. 2 subclasses: : (ratfish). No scales, one . Operculum present, bony head fused to brain case, long skinny tail. Mollusk eaters. Have a clasping organ Ratfish on the head for mating. Elasmobranchi: sharks and rays. Placoid scales, 5-7 gills. Sharks have paired fins, heterocercal tail, re placement teeth.

5. Class Osteichthyes (bony fish): 30,000 species, which is almost 50% of all vertebrates. Most nu- merous of both species and individuals among vertebrates. They have a bony skeleton, true jaws and fins, and an operculum. There are two subclasses: 1. (flesh-finned): represented today by two orders: 1. Dipnoi- : fish with lungs. 2 genera and 6 species extant, 4 in Africa, 1 in South America and 1 in Australia. 2. Crossopterygii (lobe-finned): One ancient species extant, the (hollow spine), in the genus . In bone structure and other ways Crossopterygii resemble Amphibians and are thought to be their ancestors. 2. (ray-finned): Most familiar fish; bases of fins are enclosed in body wall, fins are supported by slender ray-like bones, scales extend under the skin. Divided into 3 ‘superorders’: 1. : and . Largely cartiligenous skeleton and 15 with a heterocercal tail (unequal upper and lower lobes). 2. : and . Skeleton well ossified, tail somewhat heterocercal. 3.Teleosti: ossified skeleton, tail usually homocercal (equal lobes).

6. Class Amphibia (double life): 4000 species, 6% of vertebrate life. All have gills at some stage, lay eggs in water (or keep them moist), metamorphose, have moist per- meable skin, and have a 3-chambered heart. All adults are carnivores. Most fertilize externally. The oldest fossils are from the Devonian; they were the only vertebrates on land in the Devonian and early . The largest known amphibian was Eogyrinus (Greek, dawn tadpole), which grew -like to 15' in the Devonian. The largest today is the Chinese giant at 3+ feet. 4 orders: Chorus 1. - Urodela (tailed): . 390 species. Most are in the northern temperate zone. Internal fertilization (via packets), well defined limbs, tails. 2. Anura (tailless): . 3843 species. Jumping adaptation (pelvic girdle fixed to vertebral column, posterior fused into urostyle, radioulna), specialized tongue. 3. Apoda- (legless ones): Burrowing amphibians. 165 species. World wide in the tropics. In ternal fertilization, eggs or live birth, often blind, no trace of limb girdle, have scales (the only amphibians that do). 4. - Sirens: 6 families, 36 genera, 165 species.

7. Class Reptilia (Greek, ‘crawling’): 6000 species, 14% of vertebrate species. 8 charac- teristics: 1) exothermic, 2) 3-chambered heart and partial separation of blood flow, 3) amniotic egg, 4) precotial young (miniature adult and no parental care), 5) lungs, 6) epidermal scales, 7) complex lower jaw, 8) differentiation of vertebra into cervical, lumbar, thoracic, sacral, caudal. Cotylosaurs ('stem ') were amphibian-like creatures (now extinct) that laid an amniotic egg. There are 7 subclasses: 1. Anapsida (Gr, no openings in the near the temples): 240 species, . Garter very little changed since the , which makes the one order, Chelonia, the most primitive living or- der. Characteristics include: amphibian limbs (permanent 'pushup'), 2) skull (no fenestra- gaps in skull), 3) conspicuous bony covering dorsally and ventrally, the carapace and the plastron. 2. : ichthoysaurs. Euryapids (a single hole in the temple region), -like. Extinct. 3. Synaptosauria: plesiosaurs. Euryapids, aquatic or semi-aquatic, long neck with thin body. Extinct. 4. ('scaled reptiles'): Two orders: 1. Rhycocephalia ('snout-head'): single species, the Tautora (Mauri, 'black spine') or Sphenodon ('wedge-tooth') of New Zealand). . 2. ('scaly'): Lizards and . Modified . The largest is the , to 10' and 365 lbs. Two suborders: 1. Lacertilia: Lizards. 3000 species. 2. Serpentes: Snakes. 3000 species. Ancestral snakes were apparently burrowing lizards. Have chemical sensor tongue, keen eyes, no ears, left lung is reduced or absent. 5. Archosauria ('ruling reptiles'): 23 living species. The are/were included here. Diapsid (two holes in the temple region of the skull). 1 living and 3 extinct orders: 1. : cross, , . Unchanged since the : 4- chambered heart, advanced breathing system (diaphragm), well developed voice. 2. Pterosauria: Flying reptiles. Enlarged 4th digit. Extinct. 3. Saurichia: Dinosaurs. -hipped, Quadra- and bi-pedal. Extinct. 4. Ornithisuchia: Dinosaurs. -hipped, heavily armored, quadraped. Ex tinct. Caiman 6. Synapsida: -like reptiles. --one hole in the temple region of the skull. 7. : Includes mammals and their ancestors.

16 8. Class Aves: 8600 species. 22% of vertebrates. 23 orders. Evolved from dinosaurs in Mesozoic. Characteristics: 1) feathers, 2) wings, 3) 4-chambered heart, 4) lungs, 5) hollow bones, 6) no teeth, 7) modified jaw (beak), 8) homotherms, 9) large brains, 10) scaled feet, I I ) eggs (amniotic), 12) flight. Aves appeared in the Jurrassic.

They are evolved for flight, for example the skeleton of frigate birds have a wing- span of 6 feet and weighs 4 ounces. Adaptations for flight: 1) feathers, 2) pneumatic Mountain bones, 3) thin skull, 4) toothless keritinized jaw, 5) crop and (can't chew food), 6) fusion in skeleton (= fewer bones), in the repro system: 7) lays eggs (doesn't carry fetus), 8) seasonal changes, 9) female has only 1 , 10) rapid and efficient digesting, 11) excrete uric acid (low mois- ture, small bladder). 12) high body body temp, 13) efficient to fuel muscles and metabo- lism, 14) 4 chambered heart, 15) an energy-rich diet, 16) keel on the sternum for attachment of wing muscles..

If it weren't for the preservation of its feathers, Archeopteryx ('ancient wing', 140 million years ago) would be regarded as another Archosauria. Many vertebrate zoologists argue that modern birds are living Archo- saurs and should be classified as reptiles.

9. Class Mammalia: 4500 species, 10% of vertebrates, 20 orders. Arose from Ther- apsid reptiles which showed up in the late Permian; mammals first appear in the . They coexisted with dinosaurs, and were about the size of a , proba- bly nocturnal (big eye sockets). Homeothermy may have evolved as an adaptation to nocturnal life, pre-adapting mammals to the cooler climate of the late Creta- ceous. Characteristics: 1) hair, 2) mammary glands, 3) homeothermy (constant internal temp), 4) pelvic and pectoral girdles allow efficient locomation , 5) few offspring with high parental investment 6) well developed brain.

There are 1700 species of , 875 of , 300 of , 250 of carnivores, 190 of hoofed animals. Mam- mals are divided into 3 distinct subclasses: 1. ('first beasts') or ('one orifice'--the cloaca). Early divergence, perhaps Paleo- zoic. There are only 3 species extant, the and 2 . 2. ('middle beasts') or ('pouched')- 240 species. 3. ('true beasts') or placentals- 4000 species.

The Miocene was the golden age of mammals. The radiation of species peaked at that time; since then there has been a decline in diversity and numbers. The appearance of humans outside of Africa at the end of the Pleistocene had tremendous impact on fauna, with the extinction of much of the megafauna in North and South America and in Australia.

Mammals are remarkably diverse, from tiny bats to whales. The bumblebee from Thailand and Myanmar is 2-4 cm long and weighs 1.5 grams (there are 28 grams in 1 ounce). Some blue whales are more than 30 meters long and weigh as much as 200 tons. This is the equivalent of three Brontosaurs. A blue whale heart weighs 1/2 ton; a child could crawl through the major artery leaving it.

Kingdom Plantae - Plants began to colonize land about 450 million years ago. Several adaptations were required; gametes had to disperse through a non-aquatic environment, and the plant and the had to be protected from des- iccation. Nearly all plants reproduce sexually, nearly all are capable of . All employ alter- nation of generations, all are heteromorphic, with the diploid more conspicuous in all but and allies. The 3 major stages of plant evolution are 1) the emergence onto land 450 million years ago, requiring a cuticle and jacketed gametangia; 2) , 360 million years ago, and 3) flowers (and atten- dant protected seeds), 140 million years ago. Plants are divided into 12 divisions, or phyla, as follows:

17 1. - Liverworts, 9000 species. Liverworts have 3 basic growth forms, foliose (leafy), fruitcose (stringy) and crustose (diminutive attached everywhere to substrate).

2. Anthocerotophyta- , 100 species. Hornworts grow with green, flat- tened thallus; their name comes from the elongated, horn-like reproductive struc- ture. They are found throughout the world but only in damp environments. Liverwort

3. Bryophyta (Greek, ‘moss plant’)- 16,000 species. have 2 distinct adaptations for life on land, a cuticle (a waxy covering on the to prevent moisture loss) and gametes that develop in a gametangia, where they are kept moist. The male gametangia is called the antherida, in which flagellated sperm are produced. They re- quire water to swim to the female gametangia, the , where the egg releases a sugar that draws the male by forced movement. Most bryophytes have no vascular transport; they must imbibe water like a sponge. They are "elegantly adapted to a limited range of terrestrial habitats." They are not a to vascular plants. Their oldest fossils are 350 million years ago, by which time vascular plants already existed. Spagnum mosses cover about 1% of the Earth’s terrestrial surface.

4. Lycophyta (Greek, ‘ plant’): About 1,000 sp in 5 genera. They were a major part of the landscape in the Carboniferous, thriving for millions of years. One extinct line had trunks 2 meters in die and heights to 50 meters (Lepidodendron; their bark is the major constituent of carboniferous coal). The gametophytic generation is invisible un- derground for up to ten years, nurtured by symbiotic fungi. ‘Cannel coal' is derived from the massive spore accumulations of ancient . Clubmoss 5. Pteridophyta (Greek, ‘little feather plant’): and Horsetails, 12,000 species, 2/3 of which are in the tropics. Flagellated sperm require moisture to swim to archegonia, dispersal is by spores. Spores give rise to a small, pho- tosynthetic filament called a protonema, which grows into a small, heart-shaped, photosynthetic on the ground. The sporophyte grows out of this.

The follow 4 divisions are (Greek, ‘naked seed’): Gymnosperms were the first to develop physiological strategies that allowed them to be free of the pres- ence of liquid water for reproduction. In particular they replaced the flagellated sperm with pollen transported by wind. They also retained the small gameotophytic generation—the male stamens and female —within the large sporophyte gen- eration, thus protecting them from desiccation, and they developed seeds for disper- sal rather than spores. Gingko

6. Ginkgophyta- One species exists today, Ginko biloba, is the only living descendant of a group that was extensive in the Mesozoic. It is little changed from the mid-, where it appears among the first fossil plants. is very resistant to pollution and insects.

7. Coniferophyta (‘cone plant’): About 600 species in 50 genera. Among the tallest (redwoods up to 380'), largest (the General Sherman Sequoia is 80' in cir- cumference) and oldest (bristlecone pines are over 5000 years) living things on Earth. In Pinus fertilization occurs more than a year after ; cones usually take 3 years to mature. The mature seed contains tissue from three plant generations (the seed coat is from parent sporophyte, food reserves are from the female gameto- phyte, and embryo is the next sporophyte generation). The oldest in the BristleconePine fossil record dates from the Carboniferous, 300 million years ago. It is thought that their drought-proof leaves evolved in the Permian, a time of world-wide aridity.

18 8. (Latin is from Moluccan ganemu, a gnetophyte species found on the island of Ternate)- 70 species in 3 remotely related genera. Includes trifurca, Mormon tea; there are 40 or so species of Ephedra.

9. Cycadophyta- About 100 species in 9 genera, found only in tropical and subtropi- cal regions. They are more closely related to angiosperms than to other gymno- . Primary roots can be as long as 36', secondary roots harbor cyanobacteria, enabling to populate nitrate-depleted areas.

Angiosperms- Anthophyta and angiosperm are two different names for the same thing—flowering plants. The name angiosperm, which translates from the Greek as A ‘little seed case, highlights one main difference between this group and the gymnosperms, which means ‘naked seed.’ Angiosperms have an additional layer of tissue surrounding the seed.

10. Anthophyta (Greek, ‘flower plant-)- 275,000 species in 300 families. There are at least 4 evolutionary trends in flowers: 1) reduction in number of floral parts, 2) fu- sion of floral parts, 3) symmetry changed fin radial to bilateral, 4) The ovary shifted fm superior to inferior position. Flowers are often designed specifically for pollina- tion by one bird or insect. Many flowers produce ultraviolet 'nectar guides' (invisible to humans) that lead pollinating insects to nectar, and thereby position the creature for maximum pollination efficacy. Fruit often turns bright red and Saxifraga oppositifolia sweet when ripe, which attracts birds and mammals (insects cannot see red well) who are effective seed dispersers.

“There is grandeur in this view of life, with its several powers, having been originally breathed into a few forms or into one; and that, while this planet has gone cycling on according to the fixed law of gravity, from so simple a beginning endless forms most beautiful and most wonderful have been, and are being, evolved.”

“The main task of the immediate future is to assist in activating the inter-communion of all living and non-liv- ing beings in the emerging Ecozoic era of Earth development. What is most needed in order to accomplish this task is the great art of intimacy and distance: the capacity of beings to be totally present to each other while further affirming and enhancing the differences and identities of each. Thomas Berry

“The value of science remains unsung by singers: you are reduced to hearing not a song or poem, but an eve- ning lecture about it.“ Richard Feynman

“The statistical probability that organic structures and the most precisely harmonized reactions that typify liv- ing organisms would be generated by accident, is zero.“ Ilya Prigogine Recipient of two Nobel Prizes

“The human mind is not capable of grasping the Universe. We are like a little child entering a huge library. The walls are covered to the ceilings with books in many different tongues. The child knows that someone must have written these books. It does not know who or how. It does not understand the languages in which they are written. But the child notes a definite plan in the arrangement of the books - a mysterious order which it does not comprehend, but only dimly suspects.” Albert Einstein

by Dana Visalli/[email protected]/www.methownaturalist.com,