Protects brain and spinal cord from trauma, as well as supplies nutrients to nervous system tissue. It also removes waste from cerebral metabolism.
A........................
No. Medical progress is allowing us to progress and evolve in different ways. That is the only difference. Having medical progress and good medical care allows us to pursue different types of activites we wouldn't be able to pursue otherwise. This at the same time brings a different type of evolution.
Over population if i recall correctly
Answer:
Ecosystem engineers are species that modify their environment in a significant manner, creating new habitats or modifying existing ones to suit their needs.
