miacids造句

• The miacids are a paraphyletic group containing all miacoids that are not viverravids.
• Their teeth and skulls show that the miacids were less developed than modern carnivorans.
• Miacids are thought to have evolved into the modern carnivorous mammals of the order Carnivora.
• Carnivorans evolved from members of the family Miacidae ( miacids, now recognized as paraphyletic ).
• "' Miacoidea "'is a paraphyletic families of carnivores : Miacidae ( the miacids ) and Viverravidae.
• Christian Mathis has defined to make a difference between the miacids from Europe and the American genus " Miacis ".
• It has been proposed that miacids arose in North America and Europe 50-60 million years ago then later spread to Asia.
• The divergence of carnivorans from miacids is now inferred to have occurred in the middle-Eocene ( ca . 42 million years ago ).
• The transition from miacids to Carnivora was a gradual trend during the Paleocene to late Eocene, with taxa from both North America and Eurasia involved.
• In the Middle Eocene ( about 42 mya ), the miacids started to branch into two distinct groups of the order Carnivora : the Feliforms and Caniforms.
• The miacoids are divided into two groups : the miacids, with a full complement of molars, and the viverravines with a reduced number of molars and more specialized carnassials.
• The miacids did not appear until the very end of the Paleocene and are characterized by their shorter skull, and loss of contact between the calcaneum and fibula in the ankle.
• "' Miacids "'are extinct primitive carnivoramorphans within the family "'Miacidae "'that lived during the Paleocene and Eocene epochs, about 62 & ndash; 33 million years ago.
• The divergence of carnivorans from other miacids, as well as the divergence of the two clades within Carnivora, Caniformia and Feliformia, is now inferred to have happened in the middle Eocene, about 42 million years ago ( mya ).
• This combination of factors suggests that, rather than gradually declining due to pressure from rodents and similar placentals, multituberculates simply could not cope with climatic and vegetation changes, as well as the rise of new predatory eutherians, such as miacids.