Bird Brains and Humans Share the Innovative Gene

Humans and bird brains have something important in common.

A Barbados bullfinch innovation in the wild: opening sugar packets. 

Credit: Louis Lefebvre

Barbados birds

The researchers caught bullfinches and black-faced grassquits near McGill’s Bellairs Research Institute in Barbados. Bullfinches are bold, opportunistic and innovative, while grassquits are shy and conservative. They are each other’s closest relative in Barbados and are cousins of Darwin’s finches from the Galápagos islands.

In captivity, the problem-solving skills of the two species differed considerably in lab tests. Most of the bullfinches quickly figured out how to lift the lid off a jar of food, for example, while all the grassquits were stumped by the challenge. These performances were in line with the differences in the birds’ innovativeness in the wild — a trait that can help animals survive in changing environments.

Credit; McGill University

New tools for the study of wild behavior

The researchers then compared the expression of all genes in six parts of the brain of the two bird species using state-of-the-art molecular techniques, including next-generation sequencing –- the first time these tools have been used to find brain properties related to innovation and problem-solving in wild birds.

A bullfinch solving an experimental problem in Barbados. 

Credit: Louis Lefebvre

A family of genes stood out: glutamate neurotransmitter receptors, especially in the part of the bird brain that corresponds to humans’ prefrontal cortex. Glutamate receptors are known to be involved in a variety of cognitive traits in humans and other mammals. In particular a receptor known as GRIN2B, when boosted in transgenic mice, makes them better learners. Levels of that receptor were higher in the Barbados bullfinch than in the grassquit, the researchers found.

“By comparing an extremely innovative species like the Barbados bullfinch with a closely related conservative one like the black-faced grassquit, we gain insight into the evolutionary mechanisms that can lead to divergence in behavior,” Audet says. “It might be that mammals, including humans, and birds like the Barbados bullfinch use similar mechanisms to perform cognitively. If our results are confirmed in future studies, it would be a unique demonstration of convergent evolution of intelligence, involving the same neurotransmitter receptors despite the widely different brain structures of birds and mammals.”

Funding for the research was provided in part by the Fonds de recherche du Québec – Nature et technologies, the Natural Sciences and Engineering Research Council of Canada, the Howard Hughes Medical Institute, and a Hydro-Québec doctoral scholarship.

Contacts and sources:
Jean-Nicolas Audet / Cynthia Lee
 McGill University

Citation: “Divergence in problem-solving skills is associated with differential expression of glutamate receptors in wild finches,Jean-Nicolas Audet, Lima Kayello, Simon Ducatez, Sara Perillo, Laure Cauchard, Jason T. Howard, Lauren A. O’Connell, Erich D. Jarvis, Louis Lefebvre. . Science Advances, 2018; 4 (3): eaao6369 DOI: 10.1126/sciadv.aao6369