There are two main groups of bats, which are believed to have evolved independently of each other, but both from a common ancestor.

蝙蝠主要有两大类，人们认为它们是各自独立进化的，但都来自同一个祖先。

youdao

Often the development groups have little in common and no interaction with one another.

通常情况下，开发团队的共性很少，相互之间也没有交互。

youdao

Tribalism will also threaten the efficacy of international organizations, which tend to assume common interests between groups.

部落主义也将威胁到国际组织的效力，而国际组织往往承载着团体之间的共同利益。

youdao

Most analysts view it more as a movement of various local groups with the common aim of imposing Islamic-based rule.

VOA: standard.2009.03.11

Smoking - the leading cause of avoidable deaths - is now twice as common among groups in lower socio-economic groups.

BBC: Why are we so unhealthy?

Tampering with nature and being morally reprehensible -- these are common charges against stem cell research from religious and pro-life groups.

CNN: You, again: Are we getting closer to cloning humans?

It's more common in Sub-Saharan Africans, African-Americans and Native Americans than in other population groups.

CNN: Albinism