The evolution of corvid intelligence: development mechanisms and function of cognitive abilities in wild jackdaws

Contrary to their 'bird-brained' reputation, recent studies show that some bird species are capable of surprising feats of mental ability. Corvids, members of the crow family, for instance, have brains of a similar size to chimpanzees (relative to the size of their bodies) and are known to make and use tools, recognise themselves in mirrors, deceive one another and plan for the future. However, as almost all research has been conducted in captivity, we have little idea of the factors that favoured the evolution of corvid intelligence in nature. Studies of corvids in their natural environment are essential to allow us to better understand the evolution of intelligence in the animal kingdom. I will set up the first long-term, dedicated field study of corvid intelligence, using jackdaws. Jackdaws are highly sociable, inquisitive corvids that tolerate the close presence of humans, making them ideal for studies of intelligence. They also have the practical advantage over other corvid species that they will readily take to nest boxes, so they can be easily monitored and fitted with colour-rings to allow identification of individuals. I will set up multiple nest box colonies and use experiments and detailed observations of individual behaviour over five years to examine the cognitive challenges and benefits of life in jackdaw societies. One of the main driving forces behind the evolution of primate intelligence is thought to be the need to navigate the challenges of social life in complex and dynamic societies. I will play back recordings of jackdaw calls and examine their responses to determine whether they, like social primates, can recognise multiple individuals and keep track of the relationships between them. By following the behaviour of individuals throughout their lives, I will be able to determine whether jackdaws that invest heavily in forming and maintaining social relationships reap rewards in terms of their ability to compete for resources and rear offspring. Living in groups may provide important advantages because individuals can gain useful information from one another. Like children, young animals may acquire important skills by interacting with their elders. One particularly important skill may be the ability to recognise predators. I will investigate whether hearing recordings of adult alarm calls at the same time as coming across a model of a novel predator will make young jackdaws learn to avoid that predator in the future. I will also train individual jackdaws to open food puzzles in different ways and examine whether other individuals in their groups acquire the same technique and whether techniques spread between groups when jackdaws aggregate in flocks. I will then be able to investigate whether some individuals are more likely to learn than others, and whether the spread of information through groups is affected by the relationships of the individuals within them, as occurs in human societies. Laboratory studies of animal intelligence often find that only a small number of the individuals tested can successfully complete tasks. If we are to understand the evolution of intelligence, we need evidence that greater abilities are beneficial and parents' abilities are passed on to their offspring. I will present jackdaws with a series of food-finding puzzles and examine whether individuals are consistent in their tendency to solve the different puzzles and whether their performance relates to their natural ability to find food and successfully raise chicks. By swapping eggs between nests, I will also be able to investigate whether individuals' abilities are affected by the conditions they faced as chicks and examine the degree to which parental abilities are inherited.

Recent findings suggest that corvids, members of the crow family, possess sophisticated cognitive abilities comparable to those of primates. However, the vast majority of work to date has been conducted in captivity, limiting our understanding of the factors favouring the evolution of corvid intelligence in nature. I will establish the first dedicated field study of corvid cognition using a nest-box population of individually recognisable wild jackdaws, an inquisitive, voluble and highly social corvid species. Integrating approaches from psychology and evolutionary biology, this project aims to: (1) Assess the applicability of the social intelligence hypothesis for corvids by using playback experiments to determine whether jackdaws, like social primates, recognise multiple individuals, keep track of the relationships between them and derive substantial fitness from their investments in social relationships. (2) Investigate the effects of social learning on individual and group-level behaviour. Experiments will examine social learning of anti-predator behaviour by fledglings and the spread of novel skills within and between groups. Statistical models will identify learning mechanisms and examine the effects of individual characteristics and social relationships on information transmission. (3) Assess the causes and consequences of variation in cognitive ability. I will present jackdaws with novel tasks across a variety of cognitive domains, determine the extent of individual consistency across tasks, derive individual performance scores and investigate whether these correlate with measures of reproductive fitness. Cross-fostering experiments will allow assessment of genetic and developmental influences on cognitive performance. By generating insights in into the development and fitness consequences of wild corvids' cognitive abilities, this project will make an important contribution to our understanding of the evolution of intelligence.

In addition to its academic impact, this project will generate substantial benefits for the wider community. SCIENTIFIC ENGAGEMENT WITH THE PUBLIC This project addresses the evolutionary origins of intelligence and culture, topics central to our understanding of human characteristics and our relationship with the rest of the natural world. It is therefore perfectly placed to attract public interest and develop scientific engagement with the wider community. As evidenced by the popularity of nature documentaries, there is a great appetite for information about animal behaviour. More specific to this proposal, media coverage has recently generated excitement about the intelligence of corvids. I shall capitalise on this to foster interest in bird behaviour and instil excitement in scientific discovery. I have extensive media experience through my research on meerkats, including numerous newspaper, radio and television interviews (for the BBC, Canadian Broadcasting Corporation, National Public Radio and others), assisted in the production of a documentary for NHK (Japan) and contributed photographs and articles to magazines. Existing media contacts and knowledge gained during Cambridge Rising Stars and BBSRC media training courses will assist me in publicising the project to a wide audience through interviews and articles in newspapers and wildlife magazines. EDUCATION I will work with local schools, museums and the Institute of Continuing Education (ICE) in Madingley to promote education about nature in general and animal behaviour in particular. I have a great deal of teaching experience, having run lecture courses and tutorials for undergraduates from Cambridge and various American Universities (as part of a Cambridge summer school). I have also given lectures to science societies, contributed to educational children's magazines (Highlights and Yes Magazine) and run a children's workshop at the University Zoology Museum. As part of this project, I will distribute leaflets at the ICE in Madingley Hall (located in the centre of the study site), explaining the nature and purpose of my research and providing links for further information. Leaflets will be produced at the start of the project and updated every six months. I will also give an annual talk at the ICE and organise workshops at the Madingley Preparatory School and the Zoology Museum to educate and encourage young naturalists. Finally, the project will provide invaluable training and experience for a research assistant. CONSERVATION Public enthusiasm about the complex behaviour of charismatic animals is critical in highlighting conservation issues. By publicising my findings, I aim to promote widespread public interest in the striking intelligence of local birdlife and thereby foster a deeper appreciation and respect for the natural world. I will work with the Cambridge Conservation Forum, a unique alliance of conservation researchers and practitioners, to generate publicity and maximise the conservation impact of my work. AGRICULTURAL POLICY AND ANIMAL WELFARE Corvids are commonly persecuted as vermin despite their value in controlling populations of invertebrate agricultural pests (Hadjisterkotis, E. 2002 Z. Jagdwiss 49: 50-60). This project will generate data on the agricultural impact of corvid populations and help to change public perceptions. I have already had success in changing local land managers' views about corvids, and hence was granted permission to conduct research. Through an annual public talk in Madingley and continuing to work closely with land managers I will foster a greater tolerance of corvids and, if necessary, help to develop humane deterrents and trapping schemes to minimise their agricultural impact. Regular discussions with facilities managers at the Sub-Department of Animal Behaviour will allow me to apply insights on corvid development and behaviour generated by the project to improve facilities for captive birds.