Samuel Preston studies human population, or demographics, for the University of Pennsylvania.

塞缪尔·普雷斯顿在宾夕法尼亚大学研究人口统计学。

Researchers studied a large population of free-ranging macaques on an island off Puerto Rico.

研究人员对波多黎各一座岛屿上数量巨大的自由放养猕猴进行了研究。

Robert Hummer is a researcher who studies population health at the University of North Carolina.

罗伯特·哈默是北卡罗来纳大学研究人口健康的研究员。

In 2012, the Civil Rights Project at the University of California studied racial populations in schools.

2012年，加州大学的民权项目研究了学校的种族人口。

He was a lead writer of the government report and has studied polar bear populations for more than 30 years.

他是这份政府报告的主要撰稿人，研究北极熊种群已有30多年。

She's been studying the dolphin population that inhabits Shark Bay… a UNESCO World Heritage site off the coast of western Australia.

她一直在研究鲨鱼湾的海豚种群，鲨鱼湾位于澳大利亚西部海岸，是联合国教科文组织世界遗产保护地。

I studied population genetics and plant genetics.

我研究人口遗传学和植物遗传学。

So we're reaching a point, there's been all kinds of challenges before, with the complexity of studying different populations.

所以我们已经到达了这样一个阶段， 之前存在着各种各样的挑战，研究不同人群的复杂性。

By studying populations like the Shark Bay dolphins for many years, we start to see the complex ways they maintain their important social relationships.

通过多年来对鲨鱼湾海豚等种群的研究，我们开始注意到它们维持重要社会关系的复杂方式。