What caused a spike in the number of moose during the years 1990–1995?

Although there are a limited number of amino acids many different types of proteins exist because..

2. given that most biochemical (other than coal) rocks react with hydrochloric acid, what does that tell you about organisms?

The concept of keystone species is controversial among ecologists because most organisms are highly interdependent. if each of the trophic levels is dependant on all others how can we say one is most important