Evolution is surprising.
>>A spider which has evolved to drink blood. But, it can't get blood from animals that manufacture blood. So, it evolved to drink blood from animals that already drank blood. Because that's easier.
Evolution is surprising.
If the spider evolved to drink blood but at the same time couldn't get it due to it's inefficient fangs, then it would have died due to a lack of blood -- and the potential lineage would have gone with it.
Think about it, if it couldn't get blood from any other animal, how was it to survive? How did it know about fat juicy mosquitos?
Those who believe in the DOGMA of evolution treat the process as an intelligent entity, able to make conscious decisions. It's sad because there is much to be said about the theory of evolution, but it get's clouded by the adherents of the "religion" of evolution...