Development of Species Preferences in Two Hamsters, Phodopus campbelli and Phodopus sungorus: Effects of Cross‐Fostering

Abstract

Experiments were conducted to investigate species‐specific preferences in two closely related species of hamsters, Phodopus campbelli and Phodopus sungorus. Male hamsters that were raised with conspecifics spent more time investigating an anaesthetized conspecific male than a heterospecific male, and also spent more time investigating odours of conspecifics than those of heterospecifics (midventral gland, urine, and saccular secretion). Cross‐fostered P. sungorus males reversed their normal preferences, spending more time investigating stimuli (anaesthetized males and all three odours) of the foster species. Cross‐fostered P. campbelli males also investigated an anaesthetized male of the foster species more than a male of their own species, but did not show a preference for odours alone. Social experience during the 15 d immediately following weaning also influenced these preferences. If exposures during and after nesting were to heterospecifics the preference for heterospecifics was strengthened; if either period of experience was with a conspecific, this eliminated the preference for heterospecifics in P. sungorus but did not influence the lack of a preference in P. campbelli. Thus, early experience during both the nestling stage and the 15 d after weaning influenced responses to species‐typical cues in both species, but it had a more pronounced effect in P. sungorus.