KNOWLEDGE BASE

Can beavers recognise their siblings by smell alone? This study in the USA showed that yes, they can! Beavers showed less strongly territorial reactions to the scent of their sibling's anal gland secretion than to non-relatives. The same was also true for the beaver's mate, even if the mate had never met his or her partner's family. This suggests that beavers can recognise their kin by way of smelling anal gland secretion, and that unrelated beavers can learn to identify them, too. They could not distinguish between relatives by smelling castoreum samples.

By measuring beavers' activity, oxygen consumption, and metabolic rates of beavers in a zoo in Germany, scientists determined the beaver's energy needs when swimming underwater. This paper described the methods and results in detail, finding that beavers consumed more energy when resting in the water than on the land. Unsurprisingly, beavers consumed yet more when swimming in the water. The text compared beavers' swimming to other aquatic mammals and birds using this quantitative data as well as more qualitative observations of beavers' swimming technique.

In 1995, Scottish Natural Heritage proposed to assess reintroducing the Eurasian beaver to Scotland. This paper helped to confirm the causes of beavers' historic extinction: as they no longer existed, this feasibility study could proceed. Within the paper, a complete history of the beaver in Britain is set out. Beavers likely arrived in Britain 8,000 years ago, when the land bridge to mainland Europe still existed. In oral tradition, Scottish highlanders had a word for beavers which literally translates into English as 'broad tail' - very similar to the word in Welsh. Please note, this resource is not open-access.

Beaver teeth grow quickly and continuously throughout their life. They can therefore be used as records of the environment throughout their life, much like tree rings can tell you about the past. This paper reported on chemical analyses which allowed scientists to recount climate histories from beavers' teeth and bones, understanding changes in conditions such as humidity and temperature. They also tested samples from an ancient giant beaver.

Fatty acids are a group of common molecules found in animal fat. This study reported on an analysis of fatty acids in different mammals. It found that beavers had high levels of a specific class of fatty acids called Δ9-monounsaturated fatty acids, which may allow them to adapt to colder temperatures. Please note, this resource is not open-access.