25 Q 1

Compared with aquatic habitats, terrestrial habitats offer both advantages and challenges for an animal making a transition from water to land. Summarize how these differences might have influenced the early evolution of tetrapods.

The differences between aquatic habitats and terrestrial habitats making a transition from water to land because movement from water to land is the most dramatic event in animal evolution because it involves invasion of a physically hazardous habiat. Freshwater enviornments were unstable and during the dry periods many pools and streams evaporated, water became foul. and dissolved oxygen dissapeared. Gills were unsuitable because in air, the fillaments collapsed.

Movement onto land was clearly a revolution in vertebrae history.During seasonal droughts, aquatic vertebrae were forced to move to other pools. Recent discovery of more complete fossils of the earliest known tetrapods changes. A consensus emerging now is that tetrapods evolved their limbs underwater and only later, for reasons unknown, moved onto land.

Unless otherwise stated, the content of this page is licensed under Creative Commons Attribution-ShareAlike 3.0 License