| MadSci Network: Evolution |
Therapsids evolved from terrestrial reptiles that evolved from aquatic ancestors (fish and amphibians). All have organs that perform the functions of kidneys. These organs (the archinephros) have been modified to form the metanephric kidneys of most terrestrial vertebrates, such as the therapsids.
The archinephros is a critical organ. Its primary
function is to maintain the internal "homeostatic" balance of salt and water
within the organism.
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