A 3-base deletion in the AAUAAA sequence in the 3' untranslated region of an mRNA that eliminates the AAU, thereby preventing RNA polymerase from polyadenylation the mRNA would have the effect of; decreasing the number copies of the polyeptide that would be translated from this mRNA. A deletion is a mutation in which a part of a chromosome or a sequence of DNA is lost during DNA replication.
The best answer would be "research reasons why species change over long periods of time"
if not i apologize but this is my best guess<span />
During nitrogen fixation, bacteria breaks nitrogen gasses down into a usable form for plants.
Seminal vesicles
prostate gland
bulbourethral glands
I hope this helped. :)