Beavers in the Wetlands

The North American beaver (Castor canadensis) is one of two living species of beaver, along with its Eurasian counterpart. They are, of course, rodents - they are related to gophers - and relatively large ones at that. They are found across all but the most treeless parts of the US and Canada, as well as the border regions of northern Mexico; they have even been introduced to Finland, Belgium, and Argentina. They are a relatively common species across much of this range, something that has been helped in recent decades by restrictions on hunting.

Nonetheless, while not endangered themselves, they can be key to maintaining ecosystems, not least because they are one of the few nonhuman species that substantially modifies the land around them. Their ability to alter wetland habitats by dam-building has been identified as a key factor in maintaining other species at greater risk, such as amphibians in the Rocky Mountains. On top of which, their habit of cutting down trees affects the composition of the forests in which they live.

Eocene (Pt 2): In the Jungles of Europe

Heterohyus

During the Eocene epoch, Europe was very different from the way it is today. For one thing, it was still separated from Asia, with the Turgai Strait running between the two, roughly from what would now be the Black Sea to the Arctic Ocean. But, were you to look at a map without any modern day context, you probably wouldn't call it a continent, because it wasn't a single landmass, but a chain of large islands.

The biggest of these lay to the north, encompassing Scandinavia and the lands to the east. Just south of that, the second-largest was the one that would later become Britain, France, Germany, and some of their smaller neighbours. A smaller, but still sizable, Iberian island lay to the southwest, and a collection of low-lying ones occupied the south and east, with the more mountainous parts of that region having yet to form.

But, even if you didn't know the changes in the geography, if you could simply travel back in time to the Early Eocene and look around you, it wouldn't feel much like Europe. The continent was closer to the equator than it was now - northern Germany was about where Milan is today - but, even ignoring that, the world as a whole was much hotter. This is part of the reason for the islands, since there were no ice caps back then, but it means that our hypothetical time traveller would be, in almost any part of the landmass, standing in a jungle.

Viverrids: Genets of Central and Southern Africa

Rusty-spotted genet

The genets are one of the most speciose of the carnivoran genera, with at least fourteen species living across Africa and, in the case of the common genet, just beyond it. However, the majority of the species have been little studied. As small, nocturnal carnivores often dwelling in hard-to-reach places, it is relatively hard to do so, and they lack the cachet that applies to larger, more glamorous animals such as cheetahs, hyenas, or even wild cats. 

It probably doesn't help that there is not a great visual or (so far as we know) behavioural difference between them. In many cases, the easiest way to tell them apart is simply to note where they were found. There are subtle differences between them, to be sure, but you may have to look quite closely, and the variations are often matters of degree. Nonetheless, let's see what I can say as I take a look at the seven confirmed species that I didn't cover in the last one.