All articles tagged with #tetrapods
Paleontologists have named a new Permian tetrapod, Tanyka amnicola, from nine jaw fossils found in Brazil, notable for a bizarre twisted lower jaw and sideways denticles that suggest an early plant-based diet; the animal may have been up to about three feet long and lived in Gondwana-era lakes roughly 275 million years ago, making it a 'living fossil' in the stem tetrapod lineage.
Paleontologists at the Field Museum describe Tanyka amnicola, a 275-million-year-old stem tetrapod whose jaw is unlike any seen in early vertebrates: a twisted shape with backward-facing, denticle-covered teeth that likely ground plants. Once thought to be a deformity, the jaw appears to be an evolutionary design, suggesting an herbivorous lifestyle for this three-foot-long, salamander-like ancestor and revealing a long-surviving, now-extinct lineage. Only the jaw has been found, so the full appearance remains speculative.
Researchers have studied mudskippers to understand how the first animals to leave the oceans and wander onto shore would have had to figure out how to blink. Mudskippers are one of the few fish that can survive outside of water for extended periods of time thanks to their amphibian-like adaptations. By studying mudskippers, the researchers say that there’s an opportunity to understand how tetrapods may have evolved to blink millions of years ago in a separate yet similar way. The mudskipper appears to have rearranged its muscles in order to pop its eyes in and out, hinting that ancient tetrapods may have evolved in a similar way.
Mudskippers, an amphibious fish, have evolved a blinking behavior that serves many of the same purposes as human blinking, providing clues as to how and why blinking might have evolved during the transition to life on land in our own ancestors. The study shows that blinking may be among the suite of traits that evolved to allow the transition to life on land in tetrapods. The researchers analyzed the behavior with high-speed videos and compared the anatomy of mudskippers with that of a closely related water-bound fish that doesn't blink.