Mimetic accuracy and co-evolution of mimetic traits in ant-mimicking species.

Myrmecomorphy is the most frequent type of Batesian mimicry. Myrmecomorphic species differ in the accuracy with which they resemble ants; however, the hypothesis of the co-evolution of mimetic traits has been rarely tested. Here, we measured dozens of traits of color, shape, size, and behavior, and quantified objectively the resemblance between dozens of arthropod mimics and ants.

Intersexual trophic niche partitioning in an ant-eating spider (Araneae: Zodariidae).

Background: Divergence in trophic niche between the sexes may function to reduce competition between the sexes ("intersexual niche partitioning hypothesis"), or may be result from differential selection among the sexes on maximizing reproductive output ("sexual selection hypothesis"). The latter may lead to higher energy demands in females driven by fecundity selection, while males invest in mate searching. We tested predictions of the two hypotheses underlying intersexual trophic niche partitioning in a natural population of spiders.