How does the long tail rats in their struggle for survival?

Tails are significant in rats in thermoregulation. The blood vessels that run along the tails constrict and dilate in response to environmental temperatures. The other function of the tails is to maintain balance during movement of the rats such as when it is moving across telephone wire or rope.   

thinking it would be physical characteristics

regents of the university of california v. bakke, 438 u.s. 265 (1978), was a landmark decision by the supreme court of the united states. it upheld affirmative action, allowing race to be one of several factors in college admission policy.