定義： a pair bond between two adult animals of the same species – typically of the opposite sex. This pair may cohabitate in an area or territory for some duration of time, and in some cases may copulate and reproduce with only each other. Monogamy may either be short-term, lasting one to a few seasons or long-term, lasting many seasons and in extreme cases, life-long.
定義： 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.
定義： Number of individuals in a group that spends the majority of their time in a 24 hour cycle together where there is some indication that these individuals form a social cohesive unit.
定義： 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)
