Evolution What the Fossils Say and Why it Matters

236 Evolution? The Fossils Say YES!

inside of the skeleton! It had an ear region adapted for hearing in water, not on land. Yet it
also had modified the lobed fin into a tetrapod limb with as many as seven or eight fingers,
although the hand and foot were not well adapted for walking, but much better suited for
swimming or creeping along the bottom. This is also shown by the proportions of its limbs,

FIGURE 10.6. Phylogeny of the transitional series from rhipidistians through primitive tetrapods. (Drawing by
Carl Buell)

Ray-finned fish

Coelacanth

Lungfish

Eusthenopteron

Panderichthys

Elginerpeton

Ventastega

Metaxygnathus

Tiktaalik

Acanthostega

Ichthyostega

Hynerpeton

Greerpeton

Amphibians

Tulerpeton

(^400385370355340325310295) Million
years
Devonian Carboniferous