Here’s why Rattus norvegicus has taken over Europe
The black rat spread across Europe in two waves, first in Roman times and then in the Middle Ages. But today it has had to cede Europe to the ‘Norwegian’ brown rat.
The Arctic may be a long way from the industrial world, but harmful chemical substances find their way northward and concentrate in animals there. Researchers have now found a disturbing trend: concentrations of one harmful chemical family are higher in thin Arctic foxes than in their more well-fed brethern.