Data from: Polyandry and polygyny in a social rodent: an integrative perspective based on social organization, copulations, and genetics

Animal mating systems have fascinated biologists for thousands of years.
Ways to describe amating systeminclude determining social organization,
observing copulations, or using genetics to assign parentage. Social
organization can be difficult to quantify, however, documentation of
copulations is often challenging, many copulations do not produce
offspring, and genetic variation is sometimes minimal. Here we use data
from a 7-year study of wild white-tailed prairie dogs (WTPDs, Cynomys
leucurus) living in Colorado USA to estimate the frequencies of polyandry
(i.e., copulation with ≥2 males) and polygyny (i.e., copulation with ≥2
females) from three independent approaches: (1) determination of the
number of males and females living in the same territory (social
organization); (2) observations of copulations; and (3) genetic
assignments of paternity from seven polymorphic microsatellites. We
predicted that our three approaches would yield similar estimates of
polyandry and polygyny. Because a WTPD female’s period of sexual
receptivity each spring is limited to several hours on a single day, we
also predicted that frequencies of polyandry and polygyny would be lower
for WTPDs than for animals with longer periods of receptivity. Our results
did not support these predictions. For polyandry, observations of
copulations and genetics indicated similar overall percentages (27%), but
social organization indicated a much lower percentage (2%). For polygyny,
observations of copulations indicated the highest overall percentage
(84%), then social organization (59%), then genetics (46%). All three
approaches showed striking annual variation in the frequencies of WTPD
polyandry and polygyny. Long-term studies that integrate behavioral and
genetic insights can provide a detailed view of a mating system, but
feasibility will depend on ease of capture, visibility of copulations,
length of mating season, research objectives, and genetic variation.