title: Digit length may reveal unusual breeding behaviour in a seabird.
abstract: The hormonal environment experienced during prenatal development may affect adult phenotype and behaviour. Digit lengths may provide an estimate of steroid levels encountered during embryonic development in humans and other vertebrates. Finger patterns in humans have been shown to reveal sexual orientation or cooperative behaviour. We explored individual breeding behaviour in a monogamous seabird, the Balearic shearwater Puffinus mauretanicus and unexpectedly detected some cooperative breeders. Furthermore, we show evidence of correlation between digit lengths and cooperative breeding in this species. Additionally, we suggest that the first digit could be a possible indicator of prenatal steroid levels. These results are the starting point for further tests of the hypothesis that first digit length is an indicator of prenatal hormone levels in other vertebrate species. Moreover, these results may offer practical use in wild populations to study the implications of the changes in prenatal environment for adult social behaviour.
authors.affiliation: Institut Mediterrani d'Estudis Avançats IMEDEA (CSIC-UIB), Miquel Marquès 21, 07190 Esporles, Mallorca, Spain. m.genovart@uib.es
authors.forename: Meritxell
authors.initials: M
authors.lastname: Genovart
authors.forename: Maite
authors.initials: M
authors.lastname: Louzao
authors.forename: José M
authors.initials: JM
authors.lastname: Igual
authors.forename: Daniel
authors.initials: D
authors.lastname: Oro
mesh_terms: D000728:Androgens / Q000502:physiology; D000818:Animals; D001717:Birds / Q000033:anatomy & histology / Q000502:physiology; D003299:Cooperative Behavior; D005121:Extremities / Q000033:anatomy & histology; D005260:Female; D008297:Male; D012726:Sexual Behavior, Animal
chemical_list: D000728:Androgens