Definition: 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.
Definition: The mortality rate doubling time (MRDT) is considered to be a measure of the rate of ageing. It is estimated from the slope of the Gompertz curve by: MRDT = 0.693/G where G is the exponential (Gompertz) mortality rate coefficient.