Tiktaalik

Tiktaalik is a genus of extinct fish. This sarcopterygian (lobe-finned) fish from the later Devonian has many features similar to those of tetrapods (four-legged animals).

Tiktaalik lived about 375 million years ago. It is part of the transition between fish such as Panderichthys, known from fossils 380 million years old, and early tetrapods such as Acanthostega and Ichthyostega, known from fossils about 365 million years old. Its mixture of basal fish and derived tetrapod characteristics led one of its discoverers, Neil Shubin, to call Tiktaalik a 'fishapod'.John Noble Wilford, The New York Times, Scientists call fish fossil the missing mink, April 5, 2006.

This, and other species like it, prove that legs started to develop before these animals were land-based. They were shallow-water carnivorous fish, or fishapods.Clack, Jenny 2012. Gaining ground: the origin and early evolution of tetrapods. 2nd ed, Bloominton, Indiana: Indiana University Press. , () Tiktaalik was therefore a transitional fossil, and an example of mosaic evolution.


<li>Tiktaalik with limb-like fins that could take it onto land;
<li>Early tetrapods in weed-filled swamps, such as:  <li>Acanthostega which had feet with eight digits,
  <li>Ichthyostega with limbs.
Descendants also included pelagic lobe-finned coelacanth species.


 Related pages 
Tetrapod

References

Category:Fossils
Category:Extinct fish
Category:Lobe-finned fish