The reproductive life-histories of male banded mongooses

Abstract

The constraints of finite resources subjects all species to life-history trade-offs who should face costs for survival and future fecundity as a result of reproductive investment. There is not one common optimal solution for investment into different life-history traits due to variable selection pressures laying the groundwork for the wonderful diversity of life-histories we see in the wild. Where species navigate multiple bouts of reproductive activity throughout their lives, to maximise fitness they must adaptively balance reproductive investment as the costs and benefits of said activity change. Both sexes face this problem, but males overall have seen less study on their reproductive life-histories due to obstacles to the tractability of observing their reproductive activity and the assumption males invest less into reproduction. The banded mongoose research project has comprehensively overcome these obstacles through long term observations ongoing since 1995 and parallel sample collections and experiments. By harnessing the power of this long term system I uncover: adaptive reproductivity activity decisions throughout the lives of male banded mongooses (Chapter 1), the social dynamics of allomarking in banded mongoose groups which may be involved in the reproductive suppression of subordinate males (Chapter 2), the strategic use of sneaky alternative reproductive tactics by males that lose out on reproductive positions (Chapter 3), and an early mating advantage for male banded mongooses (Chapter 4). A recent development in the field is life-history trade-offs have the potential to spill over to the next generation. The balance between current reproductive investment and future fecundity and survival then expands to incorporate consequences for fecundity and survival of the next generation. I show tentative evidence of shielding against the intergenerational oxidative costs of reproduction in male banded mongooses (Chapter 6), the first indication of its kind in males, the significance of which I review in Chapter 5.