Crossword clues for therapsid
Wiktionary
n. (context biology English) Any extinct reptile of the order ''(taxlink Therapsida order)''; thought to be direct ancestors of the mammals
WordNet
n. probably warm-blooded; considered direct ancestor of mammals [syn: protomammal]
Wikipedia
Therapsida is a group of synapsids that includes mammals and their ancestors. Many of the traits today seen as unique to mammals had their origin within early therapsids, including having their four limbs extend vertically beneath the body, as opposed to the sprawling posture of other reptiles. The earliest fossil attributed to Therapsida is Tetraceratops insignis from the Lower Permian. Therapsids evolved from pelycosaurs (specifically sphenacodonts) 275 million years ago. They replaced the pelycosaurs as the dominant large land animals in the Middle Permian and were replaced, in turn, by the archosauromorphs in the Triassic, although one group of therapsids, the kannemeyeriiforms, remained diverse in the Late Triassic. The therapsids included the cynodonts, the group that gave rise to mammals in the Late Triassic around 225 million years ago. Of the non-mammalian therapsids, only cynodonts and dicynodonts survived the Triassic–Jurassic extinction event. The last of the non-mammalian therapsids, the tritylodontid cynodonts, became extinct in the Early Cretaceous, approximately 100 million years ago.
Usage examples of "therapsid".
Dimetrodon was a carnivorous pelycosaur, probably ancestral to the therapsids.
Happily, that was the stream we belonged to, and it evolved into a family of protomammals known as therapsids.
Traversodonts continued to survive nearly to the end of the Triassic, with the tritylodonts persisting into the Middle Jurassic as the last surviving therapsids.
Avisaurs and small mammals invaded the realm of the venators and other dinosaurs, along with the therapsids and suchids.
Unable to compete head to head with these aggressive new creatures, the therapsids by and large vanished from the record.
No one had ever measured how deep it was in the middle, but Professor Challenger had found it was full of fish and carried a fine population of fish-eating monsters—crocodiles, mesotherm reptiles, and aquatic therapsids.