10 members of Proboscidea

Elephants are incredible creatures. They are probably as intelligent as dolphins, and communicate in a similar way, using infrasound (low frequency sound waves) instead of ultrasonic clicks. Unlike dolphins and other members of the order Cetacea however, there are only 3 species extant today. In no particular order, 10 interesting members of the order that elephants belong to - Proboscidea:

1. Gomphotherium

This elephant ancestor lived during the Miocene and Pliocene. It is considered to be a member of the gomphotheres, a group of proboscids directly ancestral to mammoths and modern day elephants. It stood about 3m tall, and had 4 tusks, two upper incisors and 2 lower incisors. Conjecture has it that Gomphotherium used the bottom tusks to dig up aquatic vegetation.

2. Platybelodon

This is another gomphothere. The upper two tusks were reasonably small compared to the size of the animal, and were probably used for defensive purposes. The bottom 2 tusks were fused, forming a kind of shovel, which helped the animal dig up more solid vegetation than aquatic plants. It also let the animal scrape bark off trees, as modern-day elephants do. Platybelodon lived during the Miocene.

3. African elephants

The African elephants are members of the genus Loxodonta, and there are thought to be 2 extant species, the African bush elephant (familiar to everyone) and the African forest elephant, a smaller species that inhabits the African jungles, has more toenails, and shorter tusks. There are probably around 10,000 elephants of both species left in the wild.

4. Mastodons

Mastodons were members of the genus Mammut (no, not mammoths, although we'll come to those). Although some species were furry like woolly mammoths, they had larger heads and differently shaped teeth compared to mammoths, and had a differently curved spine. Their tusks were up to 5m long, and they may possibly have been hunted to extinction by humans in North America 4 million years ago.

5. Mammoths

Mammoths were members of the genus Mammuthus (confusing? Yes, I know). They survived till relatively recently, up to 4,500 years ago. Some species were up to 5m at the shoulder, and there were some furry ones (see, for example, woolly mammoth). They have been found to be more closely related to Asian elephants than to African elephants. They lived mostly in the northern hemisphere, and some examples have been preserved in permafrost till excavated by scientists (and the occasional hungry hunter). Pygmy woolly mammoths were found to have lived on several islands off the coast of California and in Siberia.

6. Asian elephants

Asian elephants belong to a genus all their own, Elephas. They split from the African elephant lineage about 5 million years ago in North Africa, and then migrated across to East Asia and the sub-continent. There are several extant subspecies, the most famous one living in India and Sri Lanka. There are also populations in Malaysia, Thailand, Indonesia and Vietnam. The Chinese one however, is extinct.

7. Palaeomastodon

Palaeomastodon was a member of an eponymous genus. It lived about 38 million years ago, and was fairly small at 1 to 2m. They had 2 short tusks in the upper jaws, and flat broad protruding teeth (not quite tusks) in the lower (also protruding) jaws to scoop swamp vegetation out of the water. It did have a trunk, although it was short and probably not as flexible as those of later proboscids.

8. Moeritherium

This is an extremely basal member of Proboscidea, so basal, in fact, that it doesn't have a trunk. It lived about 50m years ago, and is regarded as the common ancestor for all members of Proboscidea so far discovered. As with many of the others it was a swamp creature than subsisted on vegetation. It looked like a tapir, and was less than a metre high. It already had slightly protruding incisors on both the upper and lower jaws, the forerunners of tusks.

9. Stegodon

Stegodon is another proboscid that may have survived into historical times. A dwarf species was present on the island of Flores (part of Indonesia) till about 12,000 years ago. The first member of the genus however stood about 4m high, and had straight tusks that were up to 10m long. These tusks were so close together that the trunk would not have been able to hang down between them, and must have been been supported by them. Intriguingly, some may still survive today.

10. Anancus

As with most of the creatures described here, Anancus refers to both a genus and the first discovered member of that genus. This proboscid died out around the same time as the mastodons did, and looked very much like modern day elephants, and was about 4m high. However, it had shorter legs and much longer tusks in proportion to its size. These tusks jutted out straight ahead, and helped the animal push trees and shrubs over in its forest habitat.


While googling around for images for this post, I discovered a creationist website claiming to "disprove" evolution using elephants as an example. The counterproof was photographic evidence of the stegodont-like elephants in Nepal (and a page that claimed that mammoths were not extinct, but showed a rather rheumatic Asian elephant). How sad - there are so many pieces of evidence to support the existence of evolution, but some people still insist in sticking their heads into the ground and denying reality. Why? Aren't these creatures amazing enough to admire without bringing ideology (I won't dignify such claptrap with the word "religion") into it?

I don't like to end on that sour note, so I'll add one more fantastic proboscid:

11. Deinotherium

According to Wikipedia, the 3rd largest land mammal to have existed - up to 5m tall and 12 tonnes in weight. It also lived during the Miocene and the Pleistocene, and had recurved tusks in the lower jaw and no tusks in the upper jaw. The shape of the tusks is puzzling - what did the animal use them for? Digging for roots is a possibility, but the animal's size and weight suggests that it also used its lower jaw as a bark stripper, or a bulldozer to push trees down.