Amniotes are tetrapod vertebrate animals belonging to the clade Amniota, a large group that comprises the vast majority of living terrestrial and semiaquatic vertebrates. Amniotes evolved from amphibious stem tetrapod ancestors during the Carboniferous period.

羊膜动物 （Amniote）是一群四足 脊椎动物 ，包括合弓类动物（ 哺乳类 与 似哺乳爬行动物）与 蜥形类 （含爬行动物、鸟类）。 羊膜动物藉由产卵、胎生等方式繁衍，胚胎由 多层膜 来保护。 在 真兽类 哺乳动物，更演化出 羊膜 来包覆胎儿。 羊膜动物与 两栖动物 的差异在于保护胚胎的膜，与缺乏幼体变形为成体的阶段 。 羊膜动物由产卵、胎生等方式繁衍，胚胎由多层膜来保护。 羊膜动物与两栖动物的差异在于保护胚胎的膜，缺乏幼体变形为成体的阶段。 [2] 根据较广泛的 …

2024年12月16日 · 羊膜动物 （学名： Amniota）是 脊椎动物 的一个 演化支，其特征是 胚胎 在发育过程中会形成 胎膜，使其可以在远离 水体 的 陆地环境 进行 繁殖。 羊膜动物与不具备胎膜的 两栖动物 一起组成了代表 陆生 脊椎动物的 四足总纲。

Amniota, a group of limbed vertebrates that includes all living reptiles (class Reptilia), birds (class Aves), mammals (class Mammalia), and their extinct relatives and ancestors. The amniotes are the evolutionary branch (clade) of the tetrapods (superclass Tetrapoda) in …

羊膜動物 （學名： Amniota）是 脊椎動物 的一個 演化支，其特徵是 胚胎 在發育過程中會形成 胎膜，使其可以在遠離 水體 的 陸地環境 進行 繁殖。 羊膜動物與不具備胎膜的 兩棲動物 一起組成了代表 陸生 脊椎動物的 四足總綱。

Amniotes include most of the land-dwelling vertebrates alive today, namely, mammals, turtles, Sphenodon, lizards, crocodylians and birds. It is a diverse clade with over 20000 living …

2024年1月1日 · Amniotes (Amniota) form a monophyletic group that encompasses the last common ancestor of living mammals and reptiles, and all descendents of that ancestor. They are characterised by the possession of an amniote egg (or at least amniotic membranes in live-bearers) that contains the essentials for embryo development, but is protected by a ...

1997年6月1日 · Recent phylogenetic analyses of Paleozoic tetrapods have yielded startling new insights into the origin and early evolutionary history of amniotes.

Amniotes are a group of tetrapod vertebrates that have a terrestrially adapted egg. They include mammals (synapsids), and sauropsids (reptiles and birds). Amniota is defined as the most recent common ancestor of Reptilia and Mammalia, and all of that ancestor's descendants.

2019年4月17日 · Amniotes are vertebrate organisms which have a fetal tissue known as the amnion. The amnion is a membrane derived from fetal tissue which surrounds and protects the fetus. The amnion can be found within the egg, as in lizards and birds, or the amnion can simply enclose the fetus within the uterus.