| 翻訳と辞書 |
Dire wolf
The dire wolf (''Canis dirus'', "fearsome dog") is an extinct carnivorous mammal of the genus ''Canis'', roughly the size of the extant gray wolf, but with a heavier build. It evolved in North America and later moved into South America. ''Canis dirus'' is assigned to the Rancholabrean land mammal age of North America (240,000–10,000 years BP) and was among the many large carnivores and megaherbivores that became extinct in North and South America near the end of the Pleistocene epoch. Salamander Cave in the Black Hills of South Dakota has produced the oldest known fossil of what is thought to be a dire wolf. The site preserves a fauna approximately 252,000 years old, based on uranium-series dating of a horse fossil found there.〔 Its ending is associated with the Quaternary extinction event.
==Description==
The dire wolf averaged about in length and weighed between ,〔(【引用サイトリンク】title=Wolves, Coyotes, and Dogs (Genus Canis) )〕 which made it the largest species in the genus ''Canis''.〔 Limb elements are rarely found outside the La Brea Tar Pits, which makes it hard to compare the size of average individuals between populations. The dire wolf is estimated to have been 8% shorter at the shoulder than the modern Northwestern wolf, and of equal height to the typical gray wolf, but more heavily built.〔 With the exception of the canine teeth in some populations, male and female body and teeth sizes evidence no major sexual dimorphism, similar to most canines. In some populations, males’ canine teeth were considerably larger, suggesting male competition for breeding access. In other populations, lack of dimorphism in the canine teeth suggests little competition.
Despite superficial similarities to the gray wolf, the two species differed significantly. Today’s largest gray wolves would have been of similar size to an average dire wolf; the largest dire wolves would have been considerably larger than any modern gray wolf. The dire wolf is calculated to have weighed 25% more than living gray wolves.〔
Many of these characteristics were needed to fight off and prey on larger megafauna. The legs of the dire wolf were proportionally shorter and sturdier than those of the gray wolf, and its brain case was smaller than that of a similarly sized gray wolf.〔(【引用サイトリンク】title=Wolves, Coyotes, and Dogs (Genus ''Canis'') )〕
抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』
■ウィキペディアで「Dire wolf」の詳細全文を読む
スポンサード リンク
| 翻訳と辞書 : 翻訳のためのインターネットリソース |
Copyright(C) kotoba.ne.jp 1997-2016. All Rights Reserved.
|
|