As the way of illustrating our disscussion of group behavior of animals, we are going to watch what I think is a fascinating video tape about eland, one of the two major species of As(antelopes) in Africa. They live in herds about in about(up to) 200 individuals. But first, let’s go over some of the general advantages animals get from group association. Probably the most important advantage is defense against predators, samply being in a large group decreases the chances that any indvidual would(will) be the victim of the predator. Cooperated defence further increases the chance of the servival for individual and species. You’ll see in the video, that one(when) herd was attacked by hyenas, the elands deliberately drive their young into the center of a tightly passed group, the center being safer than the prephery. The herd acts in the way that increases the chances for servival of the offspring. Cooperated defence may even take more of(the form of offense). Many species of small birds will join together in group to attack the predators like owls and hawks. Another advantage to living in a group is the common sense notion that many eyes are better than single pair. It is that large detect predators at greater distance than do individuals. Of course there is a down side to live in a group also. But let watch the video before we get into that.

找我的听力贴特别好找,因为只有我的被扣过钱

lz的听力帖子真穿越。。太有喜感了。。

别人都是按天听写 你是按周听写。。。。

:loveliness:

又过一个星期咯

要为成为富婆的理想而努力啊。' t- x* E6 G8 m* l: d& s
我要向你学习