The spine is the indicator of stature
Salt concentration is the factor among the following factors given in the question that does not vary between a fast flowing river and a pond that receives no water input. The correct option among all the options that are given in the question is the second option. I hope the answer comes to your help.
The role of mass extinction in evolution. At the most basic level, mass extinctions reduce diversity by killing off specific lineages, and with them, any descendant species they might have given rise to. ... But mass extinction can also play a creative role in evolution, stimulating the growth of other branches.
