Description du projet
Le conflit sexuel violent et souvent mortel chez les insectes: causes et conséquences
Le cannibalisme sexuel, lorsqu’un partenaire d’accouplement (en général la femelle) mange son partenaire potentiel ou actuel avant, durant ou après l’accouplement, est courant chez les insectes. La mante religieuse Miomantis caffra recourt à ce cannibalisme avant l’accouplement. Les mâles sont également enclins à la «violence», luttant avec les femelles pour les contraindre à s’accoupler, perçant souvent leur abdomen ce faisant. Les causes et les conséquences de ce genre de conflit sexuel chez cette espèce ne sont pas bien comprises. Avec le soutien du programme Actions Marie Skłodowska-Curie, le projet SCISM utilisera des approches sur le terrain, en laboratoire et de modélisation pour analyser le conflit sexuel dans l’évolution du comportement cannibale et anticannibale. SCISM s’intéressera à des questions importantes non résolues sur les taxons sexuellement cannibales, y compris la manière dont le conflit sexuel dans les décisions d’accouplement façonne le comportement des mâles et des femelles.
Objectif
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.
Champ scientifique
Mots‑clés
Programme(s)
- HORIZON.1.2 - Marie Skłodowska-Curie Actions (MSCA) Main Programme
Régime de financement
HORIZON-TMA-MSCA-PF-EF - HORIZON TMA MSCA Postdoctoral Fellowships - European FellowshipsCoordinateur
20148 Hamburg
Allemagne