| 词条 | Protosiren |
| 释义 |
| name = Protosiren | fossil_range = {{Fossil range|Middle Eocene}} | regnum = Animalia | phylum = Chordata | classis = Mammalia | ordo = Sirenia | familia = †Protosirenidae | genus = †Protosiren | genus_authority = Abel, 1904 | subdivision_ranks = Species | subdivision =
}} Protosiren is an extinct early genus of the order Sirenia. Protosiren existed throughout the Lutetian and Bartonian stages of the Middle Eocene. GeographyFossils have been found in the far-flung locations like the United States (North Carolina), Egypt, France, Hungary, India, and Pakistan. EcologyLike the extant sirenians (manatee and dugong), Protosiren is thought to have fed on sea grasses as well as freshwater plants. Unlike extant sirenians, Protosiren had hind limbs. Although the limbs were well-developed, they were small and the sacroiliac joint was weak. Consequently, Protosiren is thought to have been mainly aquatic, rarely venturing on to land.[1] See also{{Portal|Paleontology}}
References1. ^Berta, Annalisa, 2017. Rise of Marine Mammals: 50 Million Years of Evolution. Johns Hopkins University Press.
External links
5 : Eocene sirenians|Transitional fossils|Prehistoric mammal genera|Taxa named by Othenio Abel|Fossil taxa described in 1904 |
| 随便看 |
|
开放百科全书收录14589846条英语、德语、日语等多语种百科知识，基本涵盖了大多数领域的百科知识，是一部内容自由、开放的电子版国际百科全书。