His theory is supported by the fact that this family shows the highest dimorphism of all the spider families. The idea that if large size were too costly a trait, selection would find other RHPs seems not to be the case. One piece of evidence I was unable to locate was the range of male sizes, or variation. Perhaps these two mechanisms together work to limit variability of size in a population. It builds a sheet web with an attached funnel of web extending down into some part of the habitat.
Sexual dimorphism is minimal with males being the smaller of the two sexes.
She discovered this by inducing encounters in the spiders natural habitat, in this case, a desert grassland of South Central New Mexico. Mature females were collected, weighed and kept in a laboratory for 24h prior to release. These 33 behaviors were divided into five categories based on their function. Contact moves such as shoving or biting. Finally, a fifth, 'Multiple function' category for movements like Approach or Circle was created.