Jolyon Troscianko

Jolyon Troscianko

New Caledonian crows (Corvus moneduloides) are the most proficient non-human tool users. They are able to manufacture complex tools from barbed leaves, select tools of an appropriate length or diameter for a specific task, or use tools in order to retrieve another tool that they desire. I am investigating aspects of the cognitive, ecological and morphological adaptations for tool use in New Caledonian crows, supervised in Birmingham by Dr. Jackie Chappell.

Does NC crow tool-use depend on a greater understanding of the physical laws governing the relations between objects? I aim to tackle this question by comparing NC crow physical cognition with parrots, which are highly intelligent non-tool-using birds.

NC crow tool-use is extremely difficult to observe in the wild, so we have developed and deployed miniature video cameras on the crows in addition to motion-triggered video monitoring of common tool-use sites. We have also used isotope analyses to determine what proportion of the crows’ diet is composed of foods that can only be acquired though tool use. These investigations reveal that crows in our study site rely heavily on tool-use for their nutrition, but they also highlight the long time it takes for immature birds to become proficient tool users. As such I have studied the tactics used by crows as they probe for wood-boring beetle larvae, investigating whether this is a simple task, or one that requires a level of skill learnt over a few years. My fieldwork is co-supervised by Dr. Christian Rutz at Oxford University.

Finally, I am investigating how the bill morphology and vision of NC crows might be adapted for tool-use in collaboration with Prof. Graham Martin. The only animal currently known to have specific morphological specialisations for tool use are humans, whose hands are adapted for holding and manipulating objects with a strength and dexterity surpassing that of any other animal. The body plan of NC crows is far more constrained than that of primates, so I aim to learn whether their tool-using lifestyles have changed this body plan from that of their relatives in the Corvus genus.