Miocene (Pt 9): The First Sabretooths in Europe

Amphimachairodus

When hyenas first evolved, they were small, tree-dwelling animals, searching for rodents, birds, and the occasional insect among the branches. By the Late Miocene, they had already begun to come down from the trees, but many were still small, and resembled a mongoose more than a modern hyena. A few, such as Thalissictis, were larger, an early step on the path to the more familiar forms of today.

During the early part of the Late Miocene in Europe, however, the older forms still dominated, evidently showing that their lifestyle was still a valid one, perhaps in part because they weren't directly competing with their more "modern" looking relatives. Nonetheless, as the Late Miocene dawned, newer species of hyena began to appear, and these had a more dog-like appearance than their relatives. As a result, it has been estimated that as many as 20 different species of hyena may have lived in Eurasia at the time, with a greater diversity than today.

Rabbit v. Rabbit

Mountain cottontail

There are literally thousands of different mammal species currently recognised. Most of them are small, and a great many of them can be quite hard to tell apart at first glance. Or even second glance, quite frankly.

The reason that they look so similar is that some body plans have been particularly effective, allowing the creatures possessing them to survive and multiply across the globe. But, if they're so similar, why doesn't one species, over the course of time, drive the other to extinction? Even if one isn't even just marginally better at doing whatever it does than the other (and, since they aren't literally identical, that's unlikely) then sheer bad luck ought to hit one or the other of them eventually.

The Pig Family: The Strange Case of the Sulawesi Pig-Deer

Sulawesi babirusa

Warthogs are fairly odd-looking animals, as are forest hogs, among others. But, at least to my mind, when it comes to wild pigs, nothing quite beats the babirusas.

These strange looking pigs inhabit the island of Sulawesi in Indonesia. Unlike most of the others in the group, this has been an island for far longer than pigs have been in existence - when sea levels were lower, most islands to the west were joined with Asia, and those to the east with Australia, but the waters around Sulawesi are so deep that it remained isolated. I've mentioned this before, in the context of warty pigs, so it's interesting to note that those channels must have been crossed by wild pigs on no less than three occasions (the third sort of Sulawesian pig, Celebochoerus, died out in the Ice Ages).

False Deer-Llamas of Bolivia

Theosodon
(the nasal bones are that 'bump' on the forehead
just forward of the eyes)

Australia is an island continent, separated from the rest of the world's landmass for millions of years, allowing it to develop its own unique wildlife, from kangaroos and wombats to bandicoots and emus. The only other island continent we have today is Antarctica, which has no native land mammals at all (or emus, obviously).

In geological terms, however, South America was also an island continent until relatively recently, only joining North America three million years ago, towards the end of the Pliocene epoch. Even today, the strip of land connecting the two is only 35 miles (60 km) or so wide at the narrowest point, both narrower and longer than that connecting Eurasia to Africa. This means that, like Australia, South America had a long history of so-called "splendid isolation", and it evolved a number of unique animals in the process.

Monkeys, Apes, and Simians

Is this an ape or a monkey? Or both?
(Answer at the bottom)

There is, it seems to me, quite a lot of confusion among the general public about the term "monkey", and exactly which species of animal it might cover. Some people refer to chimpanzees as monkeys, while others reserve it for animals with tails, such as macaques and spider monkeys. And what about baboons or gibbons? Come to that, aren't there other kinds of primate? Where do they fit in?

Or us? Are we monkeys? Are we descended from monkeys? Or neither?

In short, what precisely is a "monkey" in scientific terms? About three-and-a-half years ago, I blogged about the definition of "primate", so perhaps now I'll look at some broad types of primate, and how they fit together.

The Pig Family: Warthogs

Common warthog

Warthogs are, quite possibly, the best known species of wild pig after the wild boar itself. They are relatively common animals, readily observed in the habitats where they live (rather than hiding in dense thickets, say) and, perhaps above all, they have a striking and distinctive appearance.

The common warthog (Phacochoerus africanus) is widespread across sub-Saharan Africa, and is currently thought to have four different subspecies. Unlike other African hogs, they inhabit lush grasslands and open savanna, country dotted with trees and waterways, but neither densely forested nor the truly arid terrain of veldt or desert. Two subspecies live in the north, in the Sahel belt that separates the Congo rainforest from the Sahara, and are found right from the Atlantic coast of Mauritania to the shores of the Red Sea in Eritrea. The others are found across East Africa and pretty much the entire south of the continent outside the deserts, reaching as far as South Africa.

Miocene (Pt 8): Giant Honey Badgers and European Pandas

Indarctos

A great many predators lived in Europe in the glorious warmth of the Mid Miocene, when the continent was lush with subtropical vegetation and the herbivores that fed on it. As the climate began to turn, and the forests gave way to more open terrain, both the herbivores and the animals that preyed on them underwent a number of changes, with the latter in particular suffering some loss of diversity. (At least, so far as we can tell from the incomplete fossil record).

This affected the full gamut of mammalian carnivores, including many of the smaller, less obvious, ones. The boundary between the Middle and Late Miocene is an arbitrary one that isn't really marked by anything much in Europe, so that, to begin with, these were as numerous as ever. There were badgers, such as Sabadellictis, and even skunks, which today are not found outside the Americas.