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

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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.