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The evolutionary process through which a population becomes better suited to its environment over many generations of natural selection.
adaptive trait
A heritable feature of an individual’s phenotype that improves its chances of survival and reproduction in the existing environment.
adductor muscle
One of usually two large muscles (one anterior, one posterior) that contract to close the shell of a bivalve and maintain it in that condition; the position of these muscles is usually clearly marked on the shell interior as an adductor muscle scar or impression
An alternative form of a gene; one of the different forms of a gene that can exist at a single locus.
allopatric speciation
Speciation in which the evolution of reproductive isolating mechanisms occurs during physical separation of the populations.
Change within a lineage over evolutionary time, as opposed to cladogenesis, the splitting of lineages.
Having similar function, although different in structure and origin.
The science concerned with the shape, structure and the relationship of parts of organisms; also called morphology.
The science of farming organisms that live in water, such as fish, shellfish, and algae
Ear-shaped structures on the shells of scallops, one of their defining characteristics.