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Structural adaptation that enables an individual to blend with its surroundings, and that allows an individual to avoid detection by predators.
cardinal teeth
Hinge teeth located directly below the umbo in a heterodont hinge.
A single attribute of an organism.
The pattern formed by zones of separated pigments and of colorless substance in chromatographic procedures.
A group of organisms (usually species) that are more closely related to each other than any other group, implying a shared common ancestor.
See phylogenetic analysis
The splitting of lineages over time, with the consequent increase in numbers of taxa.
A tree diagram depicting patterns of shared characteristics and relationships of organisms, generated through phylogenetic analysis.
Two or more unrelated species with a close ecological relationship that evolve together, such that one species adapts to the changes of the other, thereby affecting each other’s evolution.
A type of symbiosis in which two (or more) individuals of unrelated species live in close proximity to one another, in which one member is unaffected by the relationship and the other benefits from it.
comparative anatomy
The comparative study of the structure of organisms with regard to homologous organs or parts.
How the vast and varied components of an organism (genes, molecules, cells, organs) function together to create life, behaviors, species interactions, ecosystems, etc.
continuous variation
Variation measured on a continuum rather than in discrete units or categories (e.g., height in human beings, shell length in bivalves).
Evolutionary change in two or more unrelated organisms that results in the independent acquisition of similar traits.
The fossilized excrement of animals.
cryptic coloration
Coloration that allows an organism to match its background and hence become less vulnerable to predation or recognition by prey.
A comb-like structure along the ventral edge of the byssal notch in scallops in which the byssal threads rest.