Current Projects

Pairs in the net: communication network approach to mating strategies

Communication in a network of individuals is a leading perspective on animal signalling evolution. A consequence of signalling in a network is "eavesdropping" by unintended receivers. Individuals can gain and use information from an interaction between a signaller and a receiver without directly participating in it, therefore at comparatively low cost. For many songbird species information is available on presence and extent of communication networks and eavesdropping in males. Females should be equally interested in eavesdropping on interactions, especially given the importance of sexual selection and the diversity of mating strategies in most species. Both sexes have a variety of reproductive options with respect to number of mates. In these situations there is a trade-off between increasing one's mating options and reducing the partner's, placing pressure on individuals to exploit all information on sexual activity of the partner. Both males and females of some species vocalise, with what has been called "quiet singing", during courtship and copulation. Eavesdropping on such vocalisation is theoretically possible and of advantage to the eavesdropper. In this project I will test if individuals modify their behaviour towards their mate on the basis of information on its fidelity, obtained through eavesdropping on copulation vocalisations. I will manipulate such information by playback experiments in the rock sparrow, a songbird with diverse mating strategies in both sexes.

There is a growing body of evidence which indicates that both sexes in most animals have a variety of mating strategy options. An individual's choice of strategy depends at least in part on the quality of available mates and the strategies that these, in turn, adopt. The mating strategies of males in relation to female quality and mating behaviour are of particular interest and little explored. I followed a project on sexual selection and mating strategies in alpine populations of the rock sparrow (Petronia petronia), together with Dr. A. Pilastro at the Biology department of the University of Padova (Italy). We performed a series of manipulations of a secondary sexual character present in both sexes, a yellow breast badge, to verify the effects on mating behaviour, parental care and the incidence of extra-pair paternity. This project is run in collaboration with Prof. T. Mingozzi, of the University of Cosenza (Italy), and with Dr. G. Tavecchia, of the University of Montpellier (France).

Biological and cultural evolution are considered to function in analogous ways, under the same mechanisms of mutation, migration, drift and selection of transmissible elements: genes and memes respectively. I investigated the interactions of cultural evolution, genetics and population dynamics in the reed bunting (Emberiza schoeniclus ssp.). This species is polytypic, mainly in bill morphology, but the exact mechanisms underlying the maintenance of the diversity are unclear. I analysed the genetic variation, the quantitative and qualitative variation of song and the resource use and distribution in a number of subspecies, and performed playback tests with songs, in order to asses the weight of each of these parameters in determining the evolutionary dynamics of populations. The project was carried out during my doctoral studies with the behavioural ecology research group of Prof. G. Marin and Dr. A. Pilastro. I also spent nine months in 1998 and three months in 1999 at the Animal Behaviour Department, University of Copenhagen (Denmark), to complete the project in cooperation with Prof. T. Dabelsteen, with whom I planned and performed the playback experiments. I was funded, for six months renewed by another three, by a research grant of the Danish Research Academy, and later by the Centre for Sound Communication at the University of Odense (Denmark).

During my stay at the Biology Department in Padova I assisted in another project of the group a long term study of reproductive ecology and communal breeding in the European dormouse (Glis glis).

Fluctuating asymmetry (FA) is considered an indirect measure of phenotypic quality and has been suggested to be involved in a number of behavioural contexts, especially those involving sexual selection and environmental stress. In migratory passerines, FA can directly impose high costs in terms of aerodynamics and affect accuracy of orientation and survival during migration. I tested the association of FA with orientation behaviour by capturing, measuring and testing in Emlen funnels the accuracy of orientation of blackcaps (Sylvia atricapilla), robins (Erithacus rubecula) and redstarts (Phoenicurus phoenicurus). To this end, I obtained a one-year scholarship in February 1995 from the University of Pavia (Italy) to do research abroad at the Population Biology Department at the University of Copenhagen (Denmark), with Prof. A. P. Møller. For the project I worked at the Christiansø Bird Station of the Copenhagen Zoological Museum, and at the Falsterbo Bird Observatory (Sweden). I also currently work on a project on the correlation between FA and body condition in migratory passerines at small island stopover sites along the Italian coast, in cooperation with Dr. F. Spina and Dr. M. Cardinale of the "Istituto Nazionale della Fauna Selvatica" in Bologna (Italy).