然而远古哺乳动物化石仍然十分罕见，主要是因为其体型太小。
But ancient-mammal fossils are still exceedingly rare, mostly because of their small sizes.
2004年，研究人员们在北极高地现场搜寻哺乳动物化石。
Researchers in the field search for mammal fossils in the High Arctic in 2004.
该地点属洞穴堆积，采集哺乳动物化石12种，石制品二千余件。
The site belongs to cave accumulation, in which there are 12 mammalian fossil species and more than 2000 pieces of paleoliths.
这些足迹化石的发现填补了这一重要地区新近纪哺乳动物化石记录的空白。
These tracks fill a gap in the record of Neogene mammals in this important part of the world and contribute significantly to our knowledge of these faunas.
与“阿蒂”一起被发掘的还有29种禽类化石和20种小型哺乳动物化石，包括枭类、鹦鹉、鼩鼱、蝙蝠和老鼠。
Ardi was found in alongside crumbling fossils of 29 species of birds and 20 species of small mammals - including owls, parrots, shrews, bats and mice.
骨骼化石附近的其他发现则显示当时处于树木繁茂期，有29种禽类化石和20种小型哺乳动物化石在此地点被发掘。
Findings near the skeleton indicate that at the time it was a wooded environment. Fossils of 29 species of birds and 20 species of small mammals were found at the site.
“要找小型哺乳动物化石，就得手脚并用跪在地上，或者直接趴在地上爬着走，”鲁吉尔说，“不怎么体面的，一整天基本就在土里滚。”
"Getting on your hands and knees, or going flat on the ground and crawling your way across, is how you find small-mammal fossils, " Rougier said. "It is not very glamorous.
在周口店北京人遗址出土的猿人化石、石制品、哺乳动物化石种类数量之多以及用火遗迹之丰富，都是同时代其它遗址所无法相比的。
For all the ape fossils, stoneware, and fossil of mammals unearthed at the Peking Man Site, other sites of the same age are not its match regarding quantity and miscellany of "fire" remains.
在周口店北京人遗址出土的猿人化石、石制品、哺乳动物化石种类数量之多以及用火遗迹之丰富，都是同时代其它遗址所无法相比的。
For all the ape fossils, stoneware, and fossil of mammals unearthed at the Peking Man Site, other sites of the same age are not its match regarding quantity and miscellany of "fire" remains.
应用推荐