Can birds use chemical cues to assess potential mates?

The aim of this research is to increase our understanding of the cues involved in mate assessment and selection. How and why animals choose particular individuals as mates and avoid others are fundamental questions in evolutionary biology. However, they commonly make mate-choice decisions that we can not explain with existing theory, and inconsistencies in mate preferences between individuals are frequent. One possible explanation is that animals are responding to sensory information to which humans are not receptive, and so have overlooked. I propose that the use of chemical information by birds may be a prominent example. Birds are known to have a sense of taste, but the traditional view that they are microsmatic (have a poor sense of smell) has precluded significant research into this area. However, there is now convincing evidence that birds not only have a functional olfactory system, but can also detect and respond to olfactory stimuli in their environment in order to find food, navigate and even to recognise conspecifics and individuals. Remarkably, however, whether birds use chemical cues to assess the quality and suitability of potential mates (as commonly occurs in other vertebrates) has never been tested experimentally. In an entirely novel set of experiments, I will (a) investigate whether an individual's odour profile (that is, the unique combination of chemicals that compose their body odour) can encode information on the genetic relatedness of potential mates, how important odour is in relation to visual and vocal cues and how odour-based kin recognition develops. I will also (b) experimentally test whether specific volatile compounds identified on the feathers can be used by females to assess the quality of potential mates. I plan to use Japanese quail (Coturnix japonica) as a model species. A huge amount is already known about their basic biology and, crucially, they are known to posses a good sense of smell. They are also known to suffer from severe inbreeding depression, and so have evolved the ability to discriminate between potential mates on the basis of their genetic relatedness; however, the cues they use are yet to be elucidated. I will address these questions using a combination of behavioural mate-choice assays and feather-odour analysis using gas chromatography-mass spectrometry (GC-MS). This is an entirely new field of research with enormous potential for discoveries that could revolutionise our understanding of avian behaviour.