Definition: The number of fossil occurrences in the Paleobiology Database (https://paleobiodb.org) that are identified as belonging to a particular taxon or any of its subtaxa.
Definition: External ear (pinna) length is a standard measurement in mammalogy, usually measured in a living mammal or a fresh mammal carcass. External ear length is measured from the base of the notch at the bottom of the ear to the apex (highest point) of the ear.
Definition: A group of species that exploit the same food resources, and/or use the same feeding or foraging methods. http://en.wikipedia.org/wiki/Guild_(ecology)