An amino acid is an organic molecule that is made up of a basic amino group (−NH2), an acidic carboxyl group (−COOH), and an organic R group (or side chain) that is unique to each amino acid.
Geographical variation refers to differences among populations in genetically based traits across the natural geographic range of a species. ... In the simplest case, we divide these factors into purely genetic versus environmental components to tease apart their relative contributions to observed phenotypic variation.
They construct dams and create an ecosystem for other species . Because of their dam building nests become available for birds, fish population increases and waterfowl population goes up