Invertebrates to Fish

  • Pikaia gracilens — extremely primitive notocord
  • Conodont— ray fins and a notocord
  • Haikouichthys — A notochord with separate vertebral elements (craniate)[1]
  • Arandaspis — Well armoured jawless fish[2]
  • Birkenia — primitive, jawless fish or fishlike vertebrate [3][4]
  • Guiyu — The oldest known bony fish[5]

Jawless fish to shark[6]

  • Cladoselache — intermediate between jawless fishes to sharks
  • Tristychius — another sharklike fish.
  • Ctenacanthus — first primitive shark.
  • Paleospinax — sharklike jaw, primitive teeth.
  • Spathobatis — First ray-like fish.
  • Protospinax — Ancestral to both sharks and skates.

Jawless fish to bony fish[7]

  • Acanthodians — similar to early bony fishes, possibly a transitional form.
  • Palaeoniscoids — primitive bony fishes.
  • Canobius, Aeduella — more advanced jaws.
  • Parasemionotus — combination of modern cheeks with more primitive features, like lungs
  • Oreochima — first teleost fish
  • Leptolepids — ancestor of modern teleost fish. Lung transformed into swim bladder.
  • Amphistium and Heteronectes — transition to the eye location of flatfishes.

Fish to amphibian[8]

  • Paleoniscoids — both ancestral to modern fish and land vertebrates.
  • Osteolepis — modified limb bones, amphibian like skull and teeth.
  • Eusthenopteron, Sterropterygion — fin bones similarly structured to amphibian feet, but no toes yet, and still fishlike bodily proportions.
  • Panderichthys, Elpistostege — tetrapod-like bodily proportions.
  • Obruchevichthys — fragmented skeleton with intermediate characteristics, possible first tetrapod.
  • Tiktaalik — a fish with developing legs. Also appearance of ribs and neck.
  • Acanthostega gunnari — famous intermediate fossil. most primitive fossil that is known to be a tetrapod
  • Ichthyostega — like Acanthostega, another fishlike amphibian
  • Hynerpeton — A little more advanced then Acanthostega and Ichtyostega
  • Labyrinthodonts — still many fishlike features, but tailfins have disappeared
  • Lungfish–A fish-that has lungs.

Primitive to modern amphibians[9]

  • Temnospondyls
  • Dendrerpeton acadianum
  • Archegosaurus decheni
  • Eryops megacephalus
  • Trematops
  • Amphibamus lyelli
  • Doleserpeton annectens
  • Triadobatrachus
  • Vieraella
  • Karaurus

Amphibian to reptile[10]

  • Proterogyrinus
  • Limnoscelis
  • Tseajaia
  • Solenodonsaurus
  • Hylonomus
  • Paleothyris

Early reptile to turtle[11]

  • Captorhinus
  • Scutosaurus
  • Odontochelys Semitestacea — partial formation of a turtle shell, showing how the hard underbelly formed first.[12]
  • Deltavjatia vjatkensis
  • Proganochelys

Early reptile to diapsid (dinosaurs and modern reptiles except for turtles)[13]

  • Hylonomus
  • Paleothyris
  • Petrolacosaurus
  • Araeoscelis
  • Apsisaurus
  • Claudiosaurus
  • Planocephalosaurus
  • Protorosaurus
  • Prolacerta
  • Proterosuchus
  • Hyperodapedon
  • Trilophosaurus

Reptile to mammal[14]

  • Paleothyris
  • Protoclepsydrops haplous
  • Clepsydrops
  • Archaeothyris
  • Varanops
  • Haptodus
  • Dimetrodon
  • Sphenacodon
  • Biarmosuchia
  • Procynosuchus
  • Dvinia
  • Thrinaxodon
  • Cynognathus
  • Diademodon
  • Probelesodon
  • Probainognathus
  • Exaeretodon
  • Oligokyphus
  • Kayentatherium
  • Pachygenelus
  • Diarthrognathus
  • Adelobasileus cromptoni
  • Sinoconodon
  • Kuehneotherium
  • Eozostrodon
  • Morganucodon — a transition between “mammal-like reptiles” and “true mammals”.
  • Haldanodon
  • Peramus
  • Endotherium
  • Kielantherium
  • Aegialodon
  • Steropodon galmani
  • Vincelestes neuquenianus
  • Pariadens kirklandi
  • Kennalestes
  • Asioryctes
  • Cimolestes
  • Procerberus
  • Gypsonictops

Dinosaur to bird[15]

  • Allosaurus –A large therapod with a wishbone
  • Coelophysis
  • Compsognathus –A small coeleosaur with a wishbone
  • Eoraptor
  • Epidendrosaurus
  • Herrerasaurus
  • Ceratosaurus
  • Compsognathus
  • Sinosauropteryx
  • Protarchaeopteryx
  • Caudipteryx
  • Velociraptor
  • Deinonychus
  • Oviraptor
  • Sinovenator
  • Beipiaosaurus
  • Lisboasaurus
  • Sinornithosaurus
  • Microraptor — a feathered bird with distinctly dinosaurian characteristics, such as its tail.
  • Xiaotingia — slightly earlier than Archaeopteryx, slightly more like a dinosaur and less like a bird
  • Archaeopteryx — the famous bird-with-teeth.
  • Rahonavis
  • Confuciusornis
  • Sinornis
  • Patagopteryx
  • Ambiortus
  • Hesperornis
  • Apsaravis
  • Ichthyornis
  • Columba One of many typical modern birds

Transitional mammalian fossils

Primates

Non-human primate to human

Cetaceans

  • Ambulocetus— an early whale that looks like a mammalian version of a crocodile
  • Indohyus — a proto-whale.
  • Basilosaurus — transition from early marine whales (Indohyus) to modern whales
  • Dorudon — Another candidate for transition from early whales to modern whales
  • Zeuglodon — a whale-like cetacean with vestigial limbs

External links

Transitional plant fossils

  • Williamsonia — an early flowering plant (“stem angiosperm”)

Rationalwiki.org

Bir Cevap Yazın

Aşağıya bilgilerinizi girin veya oturum açmak için bir simgeye tıklayın:

WordPress.com Logosu

WordPress.com hesabınızı kullanarak yorum yapıyorsunuz. Log Out / Değiştir )

Twitter resmi

Twitter hesabınızı kullanarak yorum yapıyorsunuz. Log Out / Değiştir )

Facebook fotoğrafı

Facebook hesabınızı kullanarak yorum yapıyorsunuz. Log Out / Değiştir )

Google+ fotoğrafı

Google+ hesabınızı kullanarak yorum yapıyorsunuz. Log Out / Değiştir )

Connecting to %s