Meeting Abstract
In order to survive, animals must quickly decide if certain sensory stimuli are salient, then they must assign attractive or aversive values to these stimuli and generate adaptive behavioral responses. However these value assignments vary depending on specific environmental features. We use the small yet complex nervous system of the fruit fly, Drosophila, to investigate how organisms assign appropriate value to sensory stimuli and how the local environment plays a role in modulating these assignments. It is known that flies from certain regions of the Mojave desert (D. mojavensis) prefer odors specific to the food in those areas (Date et. al 2017 & Schluter 2001). There are also necessary differences in their visual ecology and visuomotor reflexes compared to forest-dwelling (D. melanogaster) flies (Park and Wasserman, 2018). Here we measure interspecific differences in eye morphology (surface area, field of view, etc) and visual psychophysics (contrast sensitivity(CS), spatial acuity(SA), and temporal acuity(TA). We find that desert flies have larger eyes, fields of view and optical acuity but lower optical sensitivity compared to forest flies. However, desert flies demonstrate minimal loss in CS and a large loss in SA, with no notable difference in TA. The pattern of having a high acuity and low sensitivity at the optical level but a low acuity and boosted contrast sensitivity shown in behavior, suggests spatial neural summation to improve sensitivity in dim environments. These results further our understanding of how unique features of landscapes can shape visual circuitry required for adaptive behavior.
