Primary goals of welfare biology are to improve our understanding of the quality of life of animals in relation to their environments, and to find the most promising ways of helping them. There’s a wide range of topics that welfare biology can address. In studying the wellbeing of wild animals, research in evolutionary biology in general, and in the life history of animals in particular, may be very useful. This field aims to explain patterns of growth, reproduction, and death in animals, in terms of natural selection and in relation to their environments. Such knowledge can be very useful in assessing what the lives of individuals in different populations might be like.
Below is a project draft about sexual competition that illustrates the kind of life history research that could be developed in welfare biology. This research project idea is designed with a broad scope, which is why lists of possible species and welfare proxies worth considering are included.
We hope to inspire researchers interested in sexual selection and competition and other life-history related topics to design their own research projects adapted to their own circumstances. The results could improve our understanding of wild animal suffering.
Sexual selection is considered a form of natural selection that favors adaptations for acquiring mates rather than adaptations for survival.1 Although certain traits can enhance an individual’s fitness in terms of both survival and reproduction (e.g., foraging in efficient ways enhances their chances of survival and provides nutrients for the growth of sexual ornaments such as colored feathers), sexually selected traits can also hinder an individual’s survival.
In many animal species, traits that enable individuals to increase their ability to acquire mates are selected in two general ways: mate competition (intrasexual selection) and mate choice (intersexual selection). The first occurs when individuals engage in combat with rivals of the same sex, and favors characteristics of offense (weapons) such as horns, antlers, claws, and aggressive behavior. The second occurs when individuals of the same sex engage in courtship displays to attract individuals of the opposite sex, and favors the development of sexual ornaments such as colors, odors, elaborate dances, and vocalizations.2 Many of these traits have been associated with lowering the chances for survival of individuals of one sex.3 The large antlers of male moose, for example, are bulky and heavy, reducing their capacity for flight from predators, and antlers can become entangled in low-hanging tree branches and shrubs, increasing risk of death in male individuals. Bright colorations and elaborate vocalizations, such as those seen in many male birds and frogs, attract not only females, but also predators.
This suggests that sexual competition may cause individual suffering, either directly, as injuries incurred from fighting over a mate, or indirectly, as when animals engage in courtship behaviors that make them more likely to be predated. However, no studies have yet determined whether there is such a cost or have attempted to quantify it. Doing so is important, for in species with very strong sexual selection, sexual competition may be one of the main causes of mortality and suffering.
Determine the direct and indirect effects of sexual competition on the welfare of individuals belonging to species where sexual selection is a dominant selective force.
Direct and indirect effects may be assessed separately in different research projects.
For direct effects of sexual competition in the wellbeing of animals
For indirect effects of sexual competition in the wellbeing of animals
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