Descrizione del progetto
Le cause e le conseguenze dei conflitti sessuali violenti, e spesso mortali, negli insetti
Il cannibalismo sessuale, ovvero il caso in cui un soggetto (generalmente la femmina) mangia il potenziale o l’effettivo partner di accoppiamento prima, durante o dopo il rapporto, è un comportamento comune tra gli insetti. La mantide Miomantis caffra, ad esempio, lo mette in atto nella fase precedente all’accoppiamento. Anche i maschi sono proni alla «violenza»: lottano con le femmine per obbligarle ad accoppiarsi e spesso ne pungono l’addome durante il processo. Le cause e le conseguenze di tale conflitto sessuale in questa specie sono scarsamente comprese. Con il sostegno del programma di azioni Marie Skłodowska-Curie Actions, il progetto SCISM si avvarrà di approcci sul campo, di laboratorio e di modellizzazione per analizzare il conflitto sessuale nell’evoluzione di comportamenti cannibali e anti-cannibali. SCISM prenderà in considerazione importanti domande senza risposta sui taxa con cannibalismo sessuale, tra cui il modo in cui il conflitto sessuale nell’ambito delle decisioni sull’accoppiamento modella il comportamento di maschi e femmine.
Obiettivo
Sexual cannibalism, which occurs when a female eats her mate before, during or after mating, is a classic example of sexual conflict since females gain a meal but males lose their life. The risk of premature death is expected to select for cautious mating tactics that help males to secure matings and avoid being eaten. Although such tactics are common in cannibalistic species, males of the Springbok mantis, Miomantis caffra, take a far more aggressive approach, wrestling females to coerce them to mate. Males that win wrestling bouts are more likely to secure matings and avoid cannibalism, but wrestling severely wounds females whose abdomens are punctured by males' weaponised forelegs. While this harmful male behaviour appears to be a classic manifestation of sexual conflict, the exact causes and consequences of male coercion and female injury in this species are yet to be elucidated. My project aims to use field, laboratory, and modelling approaches to investigate the role of sexual conflict in the evolution of cannibalistic and anti-cannibalistic behaviour. First, to determine rates of female injury in the wild, I plan to use mark-recapture techniques to track sex-ratio and injury incidence through time in wild populations of M. caffra in Auckland, New Zealand, where the species is widespread. Second, I plan to run a series of laboratory experiments to explore whether males increase their fitness by injuring females, or whether injury is an incidental side-effect of males' drive to mate. Third, I plan to run a mesocosm experiment to examine whether an increase in the intensity of sexual conflict reduces female survival and population productivity--a key theoretical prediction that has rarely been tested. Finally, I intend to use modelling techniques to investigate, more generally, the role that sexual conflict over mating decisions plays in shaping male and female behaviour in sexually cannibalistic taxa--a relationship that is currently poorly understood.
Campo scientifico
Parole chiave
Programma(i)
- HORIZON.1.2 - Marie Skłodowska-Curie Actions (MSCA) Main Programme
Meccanismo di finanziamento
HORIZON-TMA-MSCA-PF-EF - HORIZON TMA MSCA Postdoctoral Fellowships - European FellowshipsCoordinatore
20148 Hamburg
Germania