Multimodal Signalling


One of my interests is in communication that can be perceived using more than one sensory modality, also known as multimodal signals. Many animals, including primates (humans and rhesus monkeys), spiders (wolf spiders and tropical wandering spiders), frogs (dart-poison frogs) and of course, gallinaceous birds (red jungle fowl and domestic fowl) communicate using multimodal signals. These signals occur in many different social contexts, including courtship, aggressive encounters, and food sharing.  

 

 The multimodal signal I am most interested in is a food-related display called tidbitting, which male fowl, Gallus gallus, perform upon finding food in the presence of a female. The display is composed of coaxing, cluck-like calls and repeated bobbing and twitching motions of the head and neck.   During the performance, the male repeatedly picks up and drops the food item with his beak. The display usually ends when the hen takes the food item either from the ground or directly from the male’s beak.  

  

I use a variety of techniques including high-definition video playback, 3D animations, and animatronics to address how variation in performance in the two modalities affects female behavior.

My research focuses on questions in animal communication and cognition and how the pressures created by social group living may have shaped these.


Some ongoing and past projects:

 

Why do roosters have wattles?

Males of many species perform elaborate displays in which multiple ornaments feature prominently. However, female preferences often depend upon both display movements and a subset of the ornaments. This response selectivity means that female choice cannot explain the function of nonpreferred ornaments. These structures may instead have an ancillary function. Male junglefowl possess multiple fleshy ornaments, which feature prominently during food-related displays (tidbitting). There is strong evidence for female choice based on display frequency and comb characteristics, but little evidence for choice based on wattles. Wattles are thin, elastic structures that hang loosely from a male’s lower mandibles and vary in size over a male’s lifetime. These structures swing rapidly during tidbitting, potentially increasing the area around the head and increasing image motion. Using 3D animation, we tested the prediction that wattles enhance signal efficacy and information content.

Is it good to be the king?

Stress in the dominance hierarchy

Group living place individuals in direct competition with others for similar resources. Within a dominance hierarchy, the dominant individuals typically have primary access to food, shelter and mates. However, dominance may come at a price. If subordinates are incompletely suppressed, the dominant may be forced to expend energy to monitor and to continually prevent the subordinate from accessing to the dominants preferred mates. We are examining the relationship between the dominants’ and subordinates’ behavioural types and their stress responses.