Khia Dobbinson

The oddity effect: applying principles from psychology to an ecological question


Predators face many challenges when attacking prey groups. One such challenge, for visual hunters, results from a limited channel capacity, i.e. only so much visual information can be processed at one time. This means that certain features, such as group uniformity and the high number and density of group members, can make groups more perceptually challenging, or ‘confusing’. The behavioural consequence for predators is a reduction in attack success, this is known as the ‘confusion effect’. One strategy, which is thought to help overcome the ‘confusion effect’ is where a predator targets visually distinct, or ‘odd’, individuals. This is known as the ‘oddity effect’. My work focuses on the ‘oddity effect’. With themes of attention, perception and cognition. I am interested in which prey draw the attention of predators over other group members, and what visual features might be more ‘odd’ than others.

One challenge of studying ‘oddity’ is the requirement of stimuli (prey) to be as similar as possible, differing only on a single level of ‘oddity’. To overcome this challenge computerised stimuli can be used, something experimental psychologists have been doing to study attention capture and the ‘pop-out’ effect for decades. I am currently lab based, and work with sticklebacks and humans preying on computerised stimuli.