There are other tiny creatures which take advantage of dense urban populations.

有些更小的生物会利用密集的都市人口而生存。

It has one of the densest black bear populations of any national park.

在所有国家公园中，它拥有最密集的一种黑熊种群。

When humpbacks live in denser populations, males looking for mates also have to deal with competing whales.

当座头鲸生活在更密集的种群中时，寻找配偶的雄性也必须与竞争对手鲸鱼打交道。

Eventually, it spread through dense human populations around the world.

最终， 它在世界各地人口稠密的人群中传播开来。

Second, our new stable food source led to bigger, denser human populations.

其次，我们新的稳定食物来源导致了更大、更密集的人口。

And because of their denser populations, disasters in a city affect far more people.

而且由于人口稠密，城市中的灾难会影响更多的人。

The parasites were relatively benign at that time, and malaria only became a major disease after agriculture and dense human populations arose.

当时的寄生虫相对良性，直到农业和人口稠密出现后， 疟疾才成为主要疾病。

With people around the world working from home and avoiding public transport, urban planners have begun pedestrianizing streets and reimagining how cities manage dense populations.

随着世界各地的人们在家工作并避免乘坐公共交通工具，城市规划者已经开始将街道步行化， 并重新构想城市如何管理密集的人口。

In temperate and polar climates, up to 40  meters below the surface, dense populations of giant kelp, the largest brown algae, grip  the rocky seafloor with branching roots called holdfasts.

在温带和极地气候下，在海面以下 40 米深的地方，巨型海带（最大的褐藻）密集种群通过称为固着物的分枝根抓住岩石海底。

A city in West Africa, for example, had similar challenges but compounded with very dense populations along the coast, severe land subsidence and drainage challenges that were exacerbated by poor solid waste management in some parts of the city.

例如，西非的一座城市面临着类似的挑战， 但沿海地区人口非常稠密，严重的地面沉降和排水挑战加剧了城市某些地区固体废物管理不善的问题。