The Effects of Dietary Stress on Body and Testis Measurements of a Southwestern Longlegs Spider, Physocyclus mexicanus
Date of Thesis
Currently, the physiological effects of resource allocation due to severe dietary restriction and starvation are poorly understood; and in fact, the system-wide effects of any environmental stresses on spider physiology remain relatively unstudied (Michalik and Ramirez, 2014). While work has been done with juvenile spiders on varying feeding quantity before the final molt (Higgins and Rankin, 2001), no work has been done to study the effects of reduced diet on testes of spiders. The goal of this study was to show the consequences of dietary restriction in the spider Physocyclus mexicanus (Family Pholcidae; Physocyclus Simon, 1893). Differences in several body measurements were compared including testis size as a consequence of a severely restricted diet compared to control spiders on an ad libitum diet. Smaller body size (carapace width, leg length, and palp size), reduced weight, and smaller testis size (length and volume) under severe dietary restriction was observed. It was also found that juveniles had less testis volume compared to adults on an ad libitum diet. The results of this study lend support to the idea that, for starving iteroparous spiders, resources will be reallocated less to reproductive potential and growth and more toward maintenance and survival to ensure that reproduction can occur when resources improve.
Spiders, Testes, Testis size, Low diet, High diet, Body measurements, Dietary restriction, Physocyclus mexicanus, Palps, Pedipalps, Palp development, Palp size, TPL, Pholcidae, Effects of dietary restriction on spider size, Resource
Masters Thesis (Bucknell Access Only)
Master of Science
Leocadia V. Paliulis
Wilson, Diane E., "The Effects of Dietary Stress on Body and Testis Measurements of a Southwestern Longlegs Spider, Physocyclus mexicanus" (2014). Master’s Theses. 131.