Meeting Abstract
A growing body of work demonstrates that many organisms adaptively modify their developmental environment through their metabolism, activities, and choices through a process known as niche construction (NC), which has the potential to bias selective environments and alter the rate and direction of evolution. Here we assess the influence of NC on larval development in two species of Onthophagus dung beetles that differ in the duration of larval development, and hence the opportunity for larval NC to impact developmental outcomes. Larval Onthophagus develop in subterranean brood balls made of dung and constructed by their mothers. In both nature and the laboratory, Onthophagus larvae engage heavily in several putative niche constructing behaviors within this dung ball, including mechanical manipulation of the surrounding dung and the construction of specialized feeding and pupation chambers. However, the functional attributes and fitness consequences of these putative niche constructing behaviors are unclear. Here, we utilize a novel method for eliminating larval NC from the brood ball environment, and assess the effect of this elimination on developmental rate, adult body size, and relative investment into morphological structures. We predict that preventing larvae from modifying their environment will result in decreased performance across all developmental measures, and that this effect will be most pronounced in the species that spends the longest time inside the brood ball. Consistent with our predictions, results to date suggest that eliminating niche constructing behaviors reduces adult body size, and that this effect is stronger in species with extended larval stages, supporting a role for NC in developmental outcomes. Here we present our latest results and discuss them within the context of developmental plasticity and adaptation.
