Sunday 21 July 2024

Drought and the Mother Rhino

You may be surprised to discover that the white rhinoceros (Ceratotherium simum) is not internationally listed as an endangered species. This is because it is reasonably widespread across southern Africa, poaching of the species has been in decline since 2014, largely due to effective enforcement methods. While it did almost go extinct in the late 19th century, well over 10,000 of the animals are thought to be alive today, with populations in some areas still rising in recent decades. In fact, it meets all the usual criteria for a species of "least concern", one that we wouldn't normally consider even close to being threatened.

This, of course, hides a fair bit of complexity.

Sunday 14 July 2024

Antelopine Antelopes: The Giraffe-Gazelles

Gerenuk
Despite appearances, true gazelles are not the closest living relatives of the springbok. That honour is probably tied between two other species, although there have yet to be sufficient genetic studies to absolutely nail that down - one could be closer than the other. They likely diverged from the springbok over 10 million years ago in the late Miocene, earlier than the blackbuck is thought to have diverged from the true gazelles, so it's perhaps unsurprising that they look quite different.

They also look slightly odd, and very distinctive.

The better-known of the two is the gerenuk (Litocranius walleri). The name comes from the Somali word for the animal, but it is more commonly known as the "giraffe-gazelle" in many European languages, and it's easy to see why. It is, of course, much smaller than a giraffe, with males having a shoulder height of around 100 cm (39 inches). The colour is also different, a relatively uniform reddish-brown over the back, with a paler shade in the flanks, neck, and limbs, and stark white underparts. There are also white markings on the face, around the eyes. Only the male has horns, which rise almost vertically out of the skull before curving back in an S-shape.

Sunday 7 July 2024

Giant Kangaroos: Were They Utterly Hop-less?

Most people have a clear image of what a kangaroo is: a large herbivorous animal that carries its young in a pouch and that moves by hopping about on its hind legs. There are three living species of true kangaroo, and this description does, indeed, accurately fit all of them. However, the kangaroo family, or Macropodidae, is much larger than this, with a total of 63 species, most of which can generically be described as "wallabies". 

There are also several fossil species known, stretching back to the late Oligocene, over 25 million years ago. Having only skeletal remains, and often partial ones at that, while we know that they had sufficient similarities to be placed in the same family and their teeth indicate they were herbivorous, what about the other two features: pouches and hopping?