Meeting Abstract
Head functions such as vision, olfaction and feeding are critical to an organism’s survival. Here we show how males and females of the Carolina sphinx moth Manduca sexta allocate resources to the head differently under different resource constraints (high versus low quality diet and starved versus unstarved larvae). We found that on high quality diet males and females allocated resources (measured as calories per gram) similarly to the head but on poor quality diet, larger females decreased allocation to the head whereas larger males increased their allocation of resources to the head. When starved, larger males and females allocated more resources to the head although males starved after feeding high quality diet did not change allocation. To better understand these patterns, we further investigated whether the sexes differ in how resources are allocated to functions of the head (vision, olfaction and feeding) and whether this changes with resource limitation due to diet quality or starvation. Preliminary data suggests that in general, males allocated more resources to vision (eye size) relative to females under resource limitation. Preliminary results further suggest that males allocate more resources to feeding (proboscis mass) and olfaction (antenna mass) relative to females. We further investigated how these differences in head function translate into allocation to brain volume (optic lobe, olfactory lobe and mushroom body as well as the muscles involved in nectar feeding). Overall, these results suggest that the two sexes of Manduca sexta have different resource allocation strategies to head functions and these strategies are dependent on the amount and quality of resources available.
