This would lead to a selective pressure on men to take the task of propositioning very seriously indeed.

这就导致选择性的压力，当一个男人必须相当严肃的对待他试图接近的异性。

Under the selective pressure of bats, nocturnal moths have evolved many adaptive traits to defense and evade bats.

在蝙蝠回声定位的选择压力下，夜间活动的蛾类进化出一系列防御、逃避等适应性特征。

If the individual populations' environments were exerting strong selective pressure, such differences should have been apparent.

但如果某一人群的环境真正具有很强的选择压力那么上述差异会很明显。

Scientists had assumed that great mass would have produced selective pressure for the larger sacrum, but now they know that the sacral enlargement came first.

科学家以前猜测可能是种群太大导致的竞争压力使蜥脚龙最终产生了，不过现在他们知道了蜥脚龙从何处分化而来的。

The result demonstrated that the immune selective pressure only had selective function, but not the creating - mutation function in the mutation of virus.

本研究结果显示，抗体这一免疫压力在病毒的变异中可能只起选择性作用，而不起促进变异的作用。