therapsid

1 Life is discovered on Mars in the shape of fish-lizard creatures called therapsids, although it is not plain how these beasts are able to subsist without any larger ecosystem.

2 Scientists have classified the four-legged predators as therapsids, along with the creatures that evolved into modern-day mammals.

3 As we’ll see, the rocks preserved in the Parnaíba Basin of northeastern Brazil appear to be the right age to preserve early therapsid fossils.

4 Mammals evolved from therapsids in the late Triassic period, as the earliest known mammal fossils are from the early Jurassic period, some 205 million years ago.

5 And while the team has yet to uncover any therapsids, Angielczyk says, the explorations have turned up a variety of other odd fossils.

6 But there’s still much to learn about this terrifying therapsid, and its life before the largest extinction event in the history of the planet.

7 The quicker growth rate of the archosauromorphs, which had been discovered in previous studies of dinosaurs and their relatives, meant that these animals reached sexual maturity relatively earlier than the therapsids.

8 Still, Theodor points out that the new study indicates how archosauromorphs may have become dominant because they simply "prevented the remaining, smaller therapsids from evolving larger size."

9 Synapsids also include therapsids, which were mammal-like reptiles from which mammals evolved.

10 If that’s the case, then it is necessary to explore fossiliferous rocks of approximately the right age in new geographic areas to see if we can find evidence of early therapsids.

11 The pectoral region, for example, appeared in the therapsids as they evolved longer forelimbs, positioned under the body rather than splayed to the sides.

12 Synapsids give rise to mammals, which are therapsids.

13 Romer and Price suggest that Haptodus, although too late in time to be an actual ancestor, shows "all the common features of the Dimetrodon group on the one hand and the therapsids on the other."

14 His current research involves studying how the major groups of therapsids are related, a topic that has received surprisingly little attention from paleontologists.

15 The new species, slightly larger than a wild pig, is a member of the extinct group of mammal-like reptiles called therapsids, the most abundant four-footed species during the Permian period.

16 The recent discovery of the very early therapsid Raranimus in China suggests that incomplete geographic sampling may indeed be an important factor contributing to the uncertainty surrounding the early history of therapsids.

17 The area also was ideally located to catch early therapsids or their ancestors if they were dispersing from equatorial North America to southern Africa.

18 Areas where therapsid fossils have been found are highlighted in yellow; the richest and most studied deposits are in southern Africa and Russia.

19 An alternative is that therapsid ancestors have been found in North America and/or Europe, but have not been recognized as such.

20 Many therapsids disappeared, and the few, diminutive lineages that survived faced competition from a different sort of creature—the archosauromorphs.

1 合弓亚纲

edaphosaurus

2 兽孔目

dicynodont cynodont

3 众多属

blue gecko ichthyosaur ichneumon filefish