Mouse burrowing 'in their genes'

The details of how mice burrow appear to be driven by genetics and not through learning, researchers report.

Biology has spent enormous effort in determining how genes affect physical traits, but little is known about how they affect structures animals make, such as bees' hives and beavers' dams.

Researchers reporting in Nature crossed mouse breeds and measured the burrows the resulting mice made.

The study has behavoural implications of many animals, including humans.

"Modular" genetic regions even relate to specific burrow parts, it suggests.

The findings bear out an idea first put forward by British evolutionary biologist Richard Dawkins, called "the extended phenotype".

It suggests that our view of genes as controlling only proteins in an individual is tremendously limited, and that genes "express" themselves in a rich variety of behaviours - or in this case, homes.

The study's key subjects were more than 300 oilfield mice (Peromyscus polionotus), which are known to make burrows into the ground toward a nest, and then an "escape route" from the nest to just below the surface, which they can break through easily in the case of danger.

Continued: http://www.bbc.co.uk/news/science-environment-21043380