American Mastodon

The American Mastodon
American Mastodon—The American mastodon was an elephantlike creature that inhabited North America for a much longer period of time than the mammoths. (Renata Cunha)

Scientific name: Mammut americanum Scientific classification: Phylum: Chordata Class: Mammalia Order: Proboscidea Family: Mammutidae

When did it become extinct? The American mastodon is thought to have become extinct around 10,000 years ago. Where did it live? The American mastodon was native to North America, and many remains have been found in the area immediately south of the Great Lakes.

Thousands of years ago, several species of mammoth could be found on the North American continent; however, these were not the only huge, shaggy, elephantlike beasts to be found in these lands. The mastodon, a creature that is often confused with the mammoth, lived in North America for a very long period of time—much longer than the mammoth— evolving from creatures that crossed into the New World from Asia via the Bering land bridge as early as 15 million years ago.

This enigmatic, long-dead mammal looked very much like its distant relative, the mammoth, but it was not as large as the largest of these animals, reaching a height of around 3 m, a length of about 4.5 m, and a weight of 5.5 tonnes. Its skeleton was stockier, with shorter, more robust legs than a similarly sized mammoth, and its skull was also a different shape, giving the mastodon a receding brow, rather than the big, flat forehead of their elephantine relatives. The tusks of the mastodon were very impressive, reaching lengths of around 5 m, but they were not as curved as the mammoth's. Like the mammoths, the mastodons were covered in thick, shaggy fur that was needed to ward off the cold, but it is impossible to know what color this pelage was in life—dark brown has been suggested, but we have no way of knowing. So, on the outside, the mastodons and the mammoths were very familiar, and the best way to tell them apart is to look at their teeth. The teeth of a mammoth are topped off with shallow enamel ridges, making them very effective grinding surfaces for the mashing up of grasses and other coarse plant matter. The mastodon's teeth, on the other hand, are quite different, as each one is surmounted with a small, enamel-covered cone that looks a lot like a nipple, which is where the Greek name mastodon comes from (mastos translates as "breast"; odont translates as "tooth").

The structure of the mastodons teeth gives us an idea of what these animals ate. As the teeth lacked a ridged grinding surface, we can assume that plants like grasses were off the menu for these lumbering beasts, but their dentition seems to be well suited to chopping and chewing twigs and leaves. Unlike the mammoths, which were grazing animals, the mastodon must have been a browser, feeding in the same way as modern elephants can sometimes be seen doing in the African bush—pulling branches to their mouth with their prehensile trunk. The fact that these animals fed in a different way to the mammoths is the reason why they were able to live alongside one another on the same landmass for thousands of years without coming into competition. As many mastodon remains have been found in lake deposits and in what were once bogs, it has been suggested that they spent a lot of their time in water, wading through the shallows grasping at succulent foliage with their flexible trunks.

The sharp eyes of an expert can reveal lots of telltale signs that enable us to build a picture of how the animal lived, and the remains of the mastodon are no exception. The tusks of male mastodons have been shown to bear interesting pits on their lower sides that occur at regular intervals. It has been proposed that these marks are scars, evidence of the damage caused by fights between males during the breeding season. Male mastodons must have locked tusks with the intention of driving the tip of their weapons into the heads or flanks of their opponents, incapacitating or even killing them. These violent struggles forced the underside of the tusk against its socket, damaging a point on the adornment that was revealed as it grew. Annual fighting led to a series of scars on the tusk. This is only a theory, but it offers a tantalizing insight into the behavior of these long-extinct giants.

What became of the mastodon? How come North America is no longer home to these great beasts? The honest answer is that we simply don't know; however, numerous theories attempt to explain their disappearance. Climate change has been cited as a culprit, even though the mastodons survived for millions of years through numerous cycles of global cooling and warming. A second theory is that humans hunted the mastodons to extinction during their dispersal into North America from eastern Asia 15,000 to 20,000 years ago, at the end of the latest ice age. We know that humans hunted these animals as their weapons have been found with mastodon remains. A mastodon skeleton has even been found with a spear point embedded in the bone, and even more remarkably, the individual in question managed to survive the attack as the wound had healed. Such finds tell us that our forebears hunted these animals, but they give us no idea of the intensity of this predation. A third theory is that tuberculosis drove the mastodons over the edge. Again, the tale of the bones shows that mastodons did indeed suffer from this disease, but was it enough to drive them to extinction? A plausible explanation for their disappearance is a combination of all these factors. Climate change may have put a lot of pressure on the population of these animals, and disease may have weakened them still further, with hunting bringing the final death knell.

♦ The ancestors of the mastodons evolved in North Africa around 30 to 35 million years ago. From this point of origin, they spread through Europe and Asia, eventually crossing into North America.

♦ Europe was once home to a species of mastodon, but it became extinct around 3 million years ago, leaving North America as the last refuge for these animals.

♦ As the remains of mastodons are found singly, it has been proposed that these animals did not form family groups. They may have led a solitary existence, only coming together during the breeding season, which is in contrast to modern elephants, and probably mammoths.

♦ The disease tuberculosis leaves characteristic grooves on the bones of infected animals. It is possible that diseases such as tuberculosis were brought to North America by humans as they dispersed throughout the continent.

Further Reading: Fisher, D. C. "Mastodon Butchery by North American Paleo-Indians." Nature 308 (1984): 271-72; Dreimanis, A. "Extinction of Mastodons in Eastern North America: Testing a New Climatic-Environmental Hypothesis." Ohio Journal of Science 68 (1968): 337-52.

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  • Elanor
    What year did the Mastadon become extinct?
    6 years ago
  • vincenza
    How much did american mastdom weigh?
    6 years ago
  • islay
    When mastodons became extinct?
    6 years ago
  • Venera
    When did the mastodon becomeextinct on earth?
    2 months ago

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