Early land-crawlers used their bones to process CO2

Ancient land-crawling animals may have used the complex bone structures in their skin to process carbon dioxide, deterring acid build-up.

The function of the “dermal bones” found in early tetrapod fossils has always been a mystery. A new paper suggests that the tetrapods may have used these bone structures to neutralise acidity, like some present-day amphibians and reptiles. The tetrapods would have had difficulty getting rid of bodily CO2 in other ways.