Abstracts (first author)
Female fineries revisited – are they correlated with offspring quality?
The evolution and signalling content of female ornamentation has remained an enduring challenge to evolutionary biologists. While females usually invest significant amounts of their resources, including carotenoids, in offspring, all the resources allocated to elaborate ornamentation reduce resources available for other purposes. This may in turn constrain female fitness leading to dishonest female signalling.
We review the literature for empirical studies on mutually ornamented species with conventional sex roles, by focusing on the association between female ornaments and quality of their offspring.
We find 43 papers where 33 (77 %) are bird-studies, 9 (21 %) are on fishes, and 1 (2 %) is a lizard-study. Nine of these report negative, 14 non-existing, and 20 positive associations between female ornament and offspring quality. Eighteen of the bird studies (55 %) show a positive association between the two traits investigated, whereas 5 (15 %) of the studies report a negative association. The number of fish studies, although few, is skewed in the opposite direction with 2 (22 %) and 4 (44 %) studies supporting positive and negative association, respectively. A minority of studies on carotenoids-based ornaments reports a positive association (4 of 18 studies, or 22 %) between the traits, which is low compared to studies on non-carotenoids-based ornaments (16 of 25 studies, or 64 %).
The abovementioned relative large number of studies with negative association, especially common in studies on fishes and in carotenoids-based-ornaments, challenges the generality of the direct selection hypothesis to account for female fineries. This is important since this hypothesis seems to have strong support in the recent literature on the topic. In the present paper, we also propose possible explanations for the observed differences between taxa and suggest directions and ideas for the future research on the evolution of female ornamentation.