My research on visual acuity focuses on describing cross-species variation in acuity, exploring the ecological and morphological factors underlying that diversity, and integrating measures of acuity with studies of signaling.
1. Describing the diversity of acuity across species and exploring the ecological and morphological factors underlying that diversity
Acuity varies over at least four orders of magnitude across animals with image-forming eyes, yet we know very little about the evolutionary pressures underlying this variation. To explore these ideas, in collaboration with Dr. Nick Brandley (Wooster College), I have begun developing a database of acuity across species using primary literature relating. Check back here for updates! 2. Understanding how acuity may act as a selective force on signal form Although it is now well accepted among biologists that we must account for the animal color vision when studying perception visual signals, acuity is not yet widely incorporated. I’m broadly interested in exploring how acuity may be a selective force on signal evolution. |
3. AcuityView Software
In collaboration with Dr. Sönke Johnsen, I have written and published an R Package called AcuityView (Methods in Ecology and Evolution; Caves and Johnsen 2017). AcuityView removes the spatial information from an image that is below the resolution of a given viewer, allowing any researcher to modify images based on animal acuity (see figure below for an example image). For more info on the AcuityView package, see this webpage about the software. I actively maintain and update the AcuityView package, so please feel free to contact me with feedback and suggestions.
Pigmented jellyfish tentacles, as the spatial aspects of the scene might appear from three different viewing distances to three potential prey items (the krill Thysanopoda monacantha, the Antarctic krill Euphausia superba, and the larval alewife fish Alosa pseudoharengus) and two fish large enough to destroy tentacles (the adult alewife Alosa pseudoharengus and the king mackerel Scomberomorus cavalla). Column labels show alpha-min, acuity (in degrees and cycles per degree respectively). The larger jellyfish and its tentacles were assumed to be 1m in length. Image of jellyfish from Wikimedia Commons (photographer: Chris Ruvolo). Figure from Caves et al. 2018, Trends in Ecology and Evolution.