on the human level... (evolution)

Evolution
So, I was watching a National Geographic special about Yellowstone Park last night, and it made some very interesting points. Besides being beautiful and crystal clear on my new HD, (which is why we originally watched it) it made a very good point for evolution. There are over 4,000 bison in Yellowstone Park, and about 32 different packs of 10 wolves or more. Naturally, the wolves hunt mainly bison. There is one pack in particular that are "bison specialists" according to the local park rangers. One day, the rangers received a call from some tourists who had seen that certain pack of wolves take down a bison in a relatively short period of time. In fact, when this pack normally kills a bison, they do it in about an hour, and that is fast. But the guests of the park said they saw the wolves kill a normal sized bison in only 15 minutes. Wow. So the rangers went looking for the carcass to see why it was so easy to make the kill. When they found it, they cracked open the bone and found that the bone marrow was red and clumpy. Usually it should be brown and have the consistency of peanut butter. Weak bone marrow means a sickly, dying bison. So, it is gathered that evolution is why this bison died. The pack noticed that the sick and dying bison was being selected for hunting, and they left her alone with the wolves. They decided that they would rather have a member of their herd who was sick die, than any member of the herd that was healthy. They choose to keep the healthy bison in the herd, so that the healthy bison could pass down the trait of strong bone marrow. They did what us humans should do. Our sick, dying and useless members of our "herd" are not phased out, though. We let our sick, dying and useless reproduce - and reproduce more of their kind into society. The bison herd wins. The humans haven't quite figured evolution out yet - on the human level.