Paternal behavior by Peromyscus leucopus in enclosures

Abstract

Male Peromyscus leucopus are known to exhibit well-developed paternal behavior in confined cages, but electrophoresis indicates promiscuity in this species. One explanation for this paradox is that the documented paternal behavioral patterns are laboratory artifacts. We made nocturnal observations of parental behavior in 14 families of P. leucopus in large enclosures and observed no paternal care. Males rarely entered the natal nest and when they did, remained in the nest for less than 2 min. Thus, we consider direct paternal care such as licking, retrieving, and huddling unlikely. We also failed to observe any indirect paternal investment such as nest building or food caching. The female in each of five pairs was very aggressive towards the male, continuously chasing him throughout most of the observation periods. Another three females actively prevented their mates from entering the natal nest. Paternal care probably does not contribute to the growth and survivorship of the young under natural conditions.