Meeting Abstract
Some males engage in fierce competitions using elaborate weapons to gain access to females and reproduction. Yet, not all males in these species have large or robust weapons. Weapons can become damaged and this phenomenon is surprisingly common. When weapons are compromised, males are less likely to win male-male competitions or may avoid them altogether. Thus, males in species that use weapons to secure females are likely to have evolved alternative routes to achieve reproductive success. One way may be to boost sperm production, so males can provide more ejaculate to females in the rare cases that they are encountered. In this study, we examined whether males with weapons damaged during development have increased offspring production. We induced developmental hind leg weapon damage in Narnia femorata (Hemiptera: Coreidae), a species that exhibits resource defense polygyny and is known to increase testes size when a weapon is lost during development. We then mated intact and weapon damaged males with four virgin females successively. Weapon damaged males produced more offspring with large females. We also noted behavioral differences between male groups. Large males with intact weapons mated with more females than weapon damaged males. Together, these results suggest that damaged males have a larger ejaculate and may be strategically investing that ejaculate in fewer females, leading to the increase in overall reproductive success. When weapon damage limits male access to females, they are able to employ an alternative reproductive strategy to counteract their diminished opportunities to mate. This strategy may help maintain variation in a population and relax the strength of sexual selection on these weapons.
