Daily at the same time on farms and in villages the cock shout sounds. To learn what awakes these unruly birds in so early hour, researchers try still. And each new zoologist answers this question in own way, and everyone finds new proofs to the arguments.
It is possible to call a surface of a pond, the river, a pool and any other reservoir a unique ecological niche safely. The fact is that two absolutely different environments for dwelling of living organisms – water and air are concentrated on a surface of these reservoirs.