ИСТИНА

In many rodents, females play a crucial role in pair formation, choosing a mate based on its chemical signals. The goal of the study was to reveal a possible role of the chemoanalytical abilities (CA) in mate choice in Djungarian hamster (Phodopus sungorus) females. Previously, CA have been described as the abilities of hamster males to distinguish the odor of one individual in a mixture of excreta from several conspecifics. CA are stable, genetically determined feature of an animal and varies significantly between individuals. This allowed us to select males with extreme values of this trait - high CA (HCA, males that could analyze urine mixtures that consist of seven individual samples) and low CA (LCA, males that are able to analyze urine mixtures that consist of 2-3 individual samples). Based on preliminary observations we hypothesized that in two choice test female hamsters will prefer urine odor of HCA males. The results supported the hypothesis – females investigated urine of HCA males significantly longer than that of LCA males. A total urine protein concentration, as a potential marker of CA, was not found different between HCA and LCA males. However, it cannot rule out an involvement of, e.g., MHC and/or lipocalins, in CA coding. As CA are mediated by cognitive processing mechanisms, such as memory and analysis, the results provide first evidence that in rodents mate choice may be determined by chemosignals coding cognitive traits of the partner.