Dr Ei-Ichi Izawa is an animal psychologist at Keio University in Japan who spends his days building a deeper understanding of the evolution of animal behaviour at different levels. ‘Humans and primates have evolved body types, or morphologies, to support dextrous foraging behaviours controlled in real time using visual feedback,’ he explains. His latest work is on a project called ‘Body Control and Neural Underpinnings in Birds’, which draws on a range of multidisciplinary approaches to understand more about the differences in convergent evolution between birds and primates. ‘Some crows, finches and parrots also display complex behaviours including tool use, but to date no-one has established whether these birds can similarly rapidly adjust their body movements according to what they see. Our project seeks to fill this gap in knowledge,’ says Izawa. The project has two main objectives. Firstly, an experiment has been designed to carefully compare the pecking ability of pigeons and crows with an extended bill, to determine if the birds’ feeding ability is compromised. Secondly, the team is exploring the neural mechanisms behind any observed movement adjustments to the artificially extended body part. As Izawa notes, the project is important to better understand the reasons for convergent evolution of behaviours between disparate groups of animals and also to shed light on how and why some species, including humans, have evolved complex and sophisticated cognitive abilities. The multidisciplinary project is supported by funding from the Japan Society for the Promotion of Science and is currently entering its second phase, having already made some important discoveries. Izawa outlines how primates (including humans) hands and limbs are visually guided. ‘This means movements can be instantly adjusted in response to an observation, for instance a prey animal fleeing’. This is such an automatic response for humans, it is hard to imagine it may not happen in all creatures. ‘However, to continually adjust movement in response to visual cues, we use sensorimotor conversion mechanisms to map the coordinates of what is perceived by the eye onto the position of body parts, in an instant,’ he observes. This requires a considerable amount of rapid feedback processing. To avoid such neural complexity, some birds such as pigeons use a highly precise and ballistic strategy without on-line correction. ‘Previous research on pigeons suggests that their feeding behaviour is based on preplanning during fixation and that no visual cues are used once the pecking movement is generated,’ notes Izawa.