Large-scale ruminant genome sequencing provides insights into their evolution and distinct traits

大规模反刍动物基因组测序帮助洞察它们的进化和特征

编辑的话

Phylogeny and characteristics of ruminants

反刍动物的系统发育关系及特征

Ruminants are a diverse group of mammals that includes families containing well-known taxa such as deer, cows, and goats. 

反刍动物是一类多样性很高的哺乳动物，其中包括很多著名的动物类群，如鹿科、牛科和羊科。

However, their evolutionary relationships have been contentious, as have the origins of their distinctive digestive systems and headgear, including antlers and horns (see the Perspective by Ker and Yang). 

然而这一类群内部的进化关系具有争议，同样存疑的还有他们特异的消化系统和头上的角，如鹿角和牛角等（详情见Ker and Yang的观点文章）

To understand the relationships among ruminants, L. Chen et al. sequenced 44 species representing 6 families and performed a phylogenetic analysis. 

为了理解反刍动物之间的进化关系，L. Chen等人对来自六个科的44种反刍动物进行了全基因组测序，并由此构建了它们的系统发育关系。

From this analysis, they were able to resolve the phylogeny of many genera and document incomplete lineage sorting among major clades. 

从他们的分析来看，他们解决了许多属之间的系统发育关系，并发现在主要分支上存在不彻底的谱系筛选。

Interestingly, they found evidence for large population reductions among many taxa starting at approximately 100,000 years ago, coinciding with the migration of humans out of Africa. 

值得注意的是，他们发现许多物种在大约十万年前都经历了一次大型的种群数量减少，这个时间点正好与人类走出非洲相符。

Examining the bony appendages on the head—the so-called headgear—Wang et al. describe specific evolutionary changes in the ruminants and identify selection on cancer-related genes that may function in antler development in deer. 

反刍动物头上的骨质附件，又称为角的，Wang等描述了反刍动物基因组里具体的进化事件和对癌症相关基因的选择，后者可能导致了鹿角的出现。

Finally, Lin et al. take a close look at the reindeer genome and identify the genetic basis of adaptations that allow reindeer to survive in the harsh conditions of the Arctic.

最后，Lin等人仔细研究了驯鹿基因组，并找到了一些允许他们在如此极端环境下存活的适应性进化。

王老师威武！但是三篇看完了没有关于瘤胃的内容啊，瘤胃是怎么进化来的呢？