Nthe hills of north carolina, several different species of wrens live in one large pine tree. this is possible because the wrens a) must have the resource competition from the other wren species. b) eat different foods found in and on the tree. c) have different natural enemies. d) breed at different times.

thrombocytopenia, which is a deficiency in blood platelets, can cause bleeding and bruising in the dermis similar to senile purpura. other possible causes include: exposure to ultraviolet rays and aging skin are common causes of senile purpura. senile purpura may also be a sign of collagen loss in the skin and bones.