A group of individuals of the same species that interact will find a mate and cross breed and produce a stronger species to survive they're environment. per Darwin's law..
1) Muscle Cell*myosin filament: changes shape and pulls on and releases actin filament allowing movement*If the myosin filament was missing or injured, it would be cause difficulty in movement2) Flagellum*Dynein arms: uses energy from ATP to "grab" the attached droplet allowing a wave like movement when pulling the droplets together* If the dynein arms was missing or injured the flagellum would have no possible way of moving causing it to stuck in mid-air
Answer:
We do not know, dire wolves mysteriously became extinct
A shut down of normal testosterone production
