Reliable signaling by chemical cues of male traits and health state in male lizards, Lacerta monticola.
In spite of the importance of chemoreception in social organization and sexual selection of lizards, there is a lack of general knowledge on how the characteristics of chemical signals mediate these behaviors. Moreover, it is unknown which are the mechanisms that might confer honesty to the information provided by chemical signals. We analyzed here whether characteristics of the lipophilic fraction of femoral gland secretions of Lacerta monticola male lizards can be related to the morphology, physical condition, and health state of the sender. Our results indicated that some male traits, such as body size, number of blue spots, and number of femoral pores and their level of fluctuating asymmetry, were related to variability in the relative proportions of some lipophilic chemical compounds found in secretions. Thus, conspecifics could obtain reliable information on the producer of a scent mark based on chemicals alone, and this might be the basis of female choice observed in this lizard. Moreover, only males with a greater T-cell immune response had higher proportions of two steroids (ergosterol and dehydrocholesterol) in their femoral secretions, which might suggest that the signal is honest and costly to produce. We suggest that only high-quality males could divert these compounds from metabolism to secretions in order to produce an exaggerated and honest "chemical ornament."
Departamento de Ecología Evolutiva, Museo Nacional de Ciencias Naturales, CSIC, José Gutiérrez Abascal 2, 28006 Madrid, Spain. Pilar.Lopez@mncn.csic.es
Pilar
P
López
Luisa
L
Amo
José
J
Martín
D000818:Animals; D049628:Body Size; D002508:Cephalometry; D004487:Edema / Q000139:chemically induced; D004912:Erythrocytes / Q000469:parasitology; D005528:Foot / Q000473:pathology; D006614:Hindlimb / Q000033:anatomy & histology; D007111:Immunity, Cellular; D008116:Lizards / Q000033:anatomy & histology / Q000469:parasitology / Q000502:physiology*; D008297:Male; D010675:Pheromones / Q000737:chemistry / Q000502:physiology*; D010835:Phytohemagglutinins / Q000494:pharmacology
D010675:Pheromones; D010835:Phytohemagglutinins