So in this case there's across-protection mutualism between these two species in which they help to avoid predation.

“因此在这种情况下这两个物种就形成了互惠共生关系。”

All of the species that fall off will form a clade.

所有脱落的物种都会形成个进化枝。

Over 90% of the world's plant species form relationships with beneficial fungi.

世界上超过 90% 的植物物种与有益真菌形成亲缘关系。

Plateaus, forests, lakes, coastlines, These various geographical features and climate conditions have helped to form and preserve widely different species.

高原、山林、湖、海岸线，这种地理和气候的跨度有助于物种的形成和保存。

In large genera the species are apt to be closely but unequally allied together, forming little clusters round other species.

在大属中，物种倾向于密但不平等地结合在起， 在其他物种周围形成小簇。

Sheela Turbek: Normally, for speciation to occur organisms have to be confined to different geographic regions in order to accumulate genetic differences.

Sheela Turbek：通常情况下，要发生物种形成，生物局限于不同的地理区域，以便积累遗传差异。

But from reasons already assigned I can by no means agree with this naturalist, that migration and isolation are necessary elements for the formation of new species.

但是根据已经给出的理由， 我决不能同意这位博物学家的观点， 即迁徙和隔离是新物种形成的要因素。

I was quite surprised by my results because they were contrasting to so many other species, where the oldest males sire the most offspring or the males with the largest territories.

我对研究结果感到非常惊讶，因为这些海豚与许多其他物种形成了对比，年纪最大的雄性海豚或是拥有最大领地的雄性海豚繁殖了最多的后代。

All that we want to show is, that where many species of a genus have been formed, on an average many are still forming; and this certainly holds good.

我们想要表明的是， 在个属的许多物种已经形成的地方，平均而言，许多物种仍在形成； 这当然很好。

Where many species of a genus have been formed through variation, circumstances have been favourable for variation; and hence we might expect that the circumstances would generally still be favourable to variation.

如果个属的许多物种是通过变异形成的， 那么环境就是有利于变异的；因此我们可以预期环境通常仍然有利于变化。

This new center of endemism is emerging a large-scale water tower that wasn't known peatlands that weren't known, source lakes that weren't known are being documented for the first time in the 21st Century.

这个全新的特有物种中心正在形成个不为人知的大型水塔，不为人知的泥炭地，以及在21世纪首次被记录下来的不为人知的源头湖泊。

And it's just about impossible to be sure  exactly which species made a particular set of tracks unless they literally died in them, so fossilized tracks aren't given the  same name as the animal that made them.

而且几乎不可能确定究竟是哪些物种形成了组特定的足迹， 除非它们真的死在了这些足迹中，因此化石足迹的名称与制造它们的动物不同。

This species forms a marked exception, crouching and creeping in compliance with the most rigorous demands of climate; yet enduring bravely to a more advanced age than many of its lofty relatives in the sun-lands far below it.

这个物种形成了个明显的例外，蹲伏和爬行符合最严格的气候要求；然而，它比远在它下面的太阳大陆上的许多崇高亲戚更勇敢地坚持到更高的年龄。