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The Evolutionary Tree of Life

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The Evolutionary Tree of Life This work by Garry Stevens is licensed under Life is easy. We know this because the Creative Commons licence CC-BY-NC-ND, earliest evidence dates from 3,800 million LUCA and is available for free from years ago (mya), shortly after the earth’s charts.archsoc.com. See terms of use there. seas stopped boiling, and complex Main source: Walker G., Dorrell R.G., chemical substances could survive without Schlacht A., Dacks J.B. (2011): Eukaryotic being ripped apart. NEOMURA Bacteria are "little bags of chemicals", EUBACTERIA systematics New walls The archaea and eubacteria are surrounded by a membrane. Usually they True bacteria collectively referred to as prokaryotes, since have either cilia (small hairs on the The cell walls of the Neomura do not contain neither have a membrane-enclosed The Tree of Life membrane surface) or flagella (a large a polymer called murein, which is present in nucleus. For almost half the history of life on bacteria. whip) to move around. They are typically 1% earth, they were the only living organisms. of the size of a eucaryote cell They reproduce by dividing in two. They are common pathogens of other organisms. Every Creature That Has Ever Lived ARCHAEA Archaea are as structurally simple as They are not pathogens, but instead are The eucarya are the product of an If the prokaryotes were easy to create, the EUCARYA True nucleus Old bacteria bacteria, but exhibit much more diverse important commensal or mutually beneficial archaeon engulfing a bacteria, and the next step to the eucaryotes was incredibly The eucaryotes have cells that contain chemical metabolisms; and can live in partners to many other organisms. latter remaining as endosymbionts within the difficult. After the last unversal common complex structures enclosed within extremely salty, hot, cold, acidic or alkaline host cell. Mitochondria and plastids are ancestor (LUCA) produced bacteria and membranes. The most important is the environments that bacteria could not classic examples. This seems to have archaea, it took 1,700 million years until the nucleus, which contains genetic material. tolerate. They are common in the oceans. happened several times, to produce first eucaryotes developed, 2,100 mya. Most eukaryotic cells also contain other different lineages. membrane-bound organelles such as mitochondria. The unikonts have a single flagellum, or are UNIKONTA Archaeplastid cells have plastids, organelles BIKONTA The bikonts are cells with two flagella and EOZOA The eozoa seem to be the earliest amoebae with no flagella; and a triple-gene Two flagella Single flagellum that provide energy by photosynthesis. two specific genes fused into one. Early animals eucaryotes, neither bikonts nor unikonts. fusion that is absent in the bikonts. Many are today parasites or commensals of other organisms. For example, they cause ARCHAEPLASTIDA HACROBIA HAROSA trichomoniasis, giardiasis, and sleeping APUSOZOA AMOEBOZOA Ancient plastids EUGLENOZOA EXCAVATA OPISTHOKONTA Acronym Footless animal Acronym True eyespots Hollowed out sickness in humans. Single posterior flagellum Changing animals Hacrobians are widely distributed in marine The harosans are a large group of organisms and freshwater environments. ranging from small unicellular creatures that produce shells, to vast kelps. Many are important parasites and pathogens, such as malaria. VIRIDIPLANTAE RHODOPLASTIDA GLAUCOPHYTA HAPTOPHYTA CRYPTOMONADA RHIZARIA HETEROKONTOPHYTA ALVEOLATA CONOSEA LOBOSEA DISCOBA METAMONADA HOLOZOA True plants Red plastids Blue-green plants Fastening plants Hidden units Root-like pseudopods Different length flagella With cavities FUNGI NUCLEARIIDAE Coned Changed units Lobed Compound word Chitin + glucans cell walls Whole animals Cristidiscoidea CHLOROPHYTA STREPTOPHYTA CERCOZOA FORAMINIFERA RADIOZOA CILIOPHORA APICOMPLEXA DINOFLAGELLA MYCETOZOA ARCHAMOEBAE Tailed animals Fungus animals Green plants Twisted plants Bearing holes Radial animals Bearing cilia Top infolds Whirling flagella The metazoa are what most people think of METAZOA CHOANOFLAGELLATE MESOMYCETOZOEA Original changing animals The chlorophytes are a large group of as animals: multicellular organisms, whose Advanced animals A Between fungi and animals marine algae. cells perform different functions. They possess Funnel animal Hox genes, which regulate embryonic development, constructing complex structures unknown in all other organisms. Slime moulds Sea lettuces Malarias Plankton Special Note: This chart shows much more Animals detail for the metazoa than other organisms, but it does not mean they are more CHAROPHYTA EMBRYOPHYTA important, nor more numerous. Amoebozoa are single-celled organisms Germ plants PARAZOA PLACAZOA ? plants Of all the bikonts, only the embryophytes EUMETAZOA Land plants Beside the animals Wide and flat animals noted for their ability to flow through their established themselves on land; and unlike True advanced animals The metazoa are the second difficult step in environments. They include the slime moulds, all other bikonts, their fertilized eggs are Both the parazoa and placozoa are evolution. It took 1,300 million years for some which can form single organisms with nurtured within the parent, and disperse as a multicellular, but neither have the eucaryotes to evolve into the simplest differentiated cells. multicellular embryo, rather than a single specialised nervous, digestive or circulatory metazoans. But after that event, life cell. systems present in the eumetazoa. exploded in diversity. Stoneworts Porifera/Sponges Trichoplax BRYOPHYTA TRACHEOPHYTA Moss plants Vascular plants ACROSOMATA CNIDARIA Sperm with acrosomes Nettles Tracheophytes, or vascular plants, have The acrosomata have a special shield specialised tissues to conduct water and Cnidaria are predators with rudimentary covering their head of their sperm. This is one other products through out the plant. nerve nets and differentiated cells. They feature separating the cnidaria from the develop from two germ layers as embryos ctenophora, which otherwise appear as (diploblasts). Mosses similar jellyfish. LYCOPODIOPHYTA SPERMATOPHYTA PTERIDOPHYTA BILATERIA ANTHOZOA SCYPHOZOA CUBOZOA HYDROZOA Wolf-footed plants Seed-bearing plants Ferns CTENOPHORA Flower animals Drinking cup animals Comb bearing Bliateral symmetry Cube shaped Water animals Club mosses Fern plants Corals, anemones Jellyfish Comb jellies Box jellies Man'o'war PROTOSTOMIA DEUTEROSTOMIA Mouth first Bilaterians are not only bilaterally In the embryonic development of the In the embryonic development of the Anus first symmetrical, but also develop from three protostomes, the dent that first forms in the deuterostomes, the dent that first forms in separate germ layers as embryos blastula becomes the organism’s mouth. the blastula becomes the organism’s anus. (triploblasts): an endoderm, mesoderm, and an ectoderm. This allows the formation of complex organs. PLATYHELMINTHES ECDYSOZOA LOPHOTROCHOZOA ACOELOMORPHA ECHINODERMATA CHORDATA XENOTURBELLIDA HEMICHORDATA Shedding animals Flat worms Compound word No coelom Hedgehog skin Notochord in embryo Strange worm Half cord All the ecdysozoans have a three-layered cuticle composed of organic material, which is periodically molted as the animal grows. Flat worms Starfish Acorn worms, graptolites PANARTHROPODA CHAETOGNATHA NEMATODA SCALIDOPHORA TROCHOZOA LOPHOPHORATA UROCHORDATA CRANIATA Long-haired jaw Thread Bearing spines Wheel animals Trochozoan larvae have two bands of cilia Bearing crests Tail cord Skull (small hairs) around their middle. The lophophorates have a fan of ciliated tentacles surrounding the mouth. Arrow worms Round worms Tunicata, sea squirts, cunji ARTHROPODA ONYCHOPHORA TARDIGRADA KINORHYNCHA PRIAPULIDA LORICIFERA ANNELIDA MOLLUSCA NEMERTINI SIPUNCULA POGONOPHORA ECHIURA BRYOZOA BRACHIOPODA PHORONIDA ENTOPROCTA CEPHALOCHORDATA VERTEBRATA Jointed feet Bearing claws Slow walking Snout in motion Penis worms Corselet (outer case) Ringed one Soft animals Greek sea nymph Small tubes Beard bearing Viper tail Moss animals Arm foot Greek myth Phoronis Anus within Head cord Backbones Velvet worms Water bears Mud dragons Earthworms, leeches Snails, squids, clams Ribbon worms Peanut worms Spoon worms Lamp shells Horsehoe worms Goblet worms Lancelets.
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