If you’ve ever visited a natural history museum, you might have seen a
grand skeleton tower over you, with giant tusks gently sloping to the
sky and a shape reminiscent of an elephant. Perhaps you thought
immediately of a woolly mammoth, the most famous elephant relative,
popularized by Manny, the grumpy mammoth in Ice Age. However, there is another relative that you most certainly have also heard of: the mastodon.
Although similar, there are key differences between mammoths and mastodons. An impressive mammoth skeleton. Image credits: Kelley Minars.
First of all, mastodons came into existence much earlier, about 27 to 30 million years ago. Mammoths are “young” by comparison, having emerged a mere 5.1 million years ago in Africa.
There were multiple mammoth species, but the famous woolly mammoth is
the baby of the bunch, emerging only 250,000-400,000 years ago.
Mammoths could be found across Eurasia and North America. Mastodons were not so widespread and called North and Central America their home (still a considerable area considering that they could be found from Alaska to central Mexico).
Although mammoths preferred cooler temperatures and mastodons
preferred warmer temperatures, they both lived in Beringia, the land
between East Siberia and Alaska that wasn’t covered by ocean during the
Ice Ages.
They lived there at the same time during the early to
mid-Pleistocene, but the mastodons left because it got too chilly for
them. Mammoths still survived in Beringia until 13,000 years ago, and a
subset that evolved to be small (about the size of a large horse) survived on arctic islands until as recently as 4,000 years ago.
To put it into perspective, the Great Pyramid was being constructed
around the same time mini mammoths were ruling an arctic island — as
crazy as it sounds, mammoths and the pyramids were around around at the
same time (for a brief period).
Lifestyle differences
Mammoths and mastodons led different lifestyles and their appearance reflects these differences.
Mastodons lived mainly in forests. Accordingly, their teeth have
cone-shaped cusps, perfect for crushing leaves and twigs. Sometimes, the
plants that animals eat are also preserved alongside their fossil
remains. Researchers who have quantified mastodon gut contents have
found a lot of twigs from coniferous trees, while another study found
mostly low, herbaceous vegetation in their guts. Therefore, they likely
browsed and grazed, changing their preference based on the season and where they were.
A mastodon depicted in its forest habitat. Image credits: Heinrich Harder (1858-1935).
On the other hand, mammoths are much more closely related to
modern-day elephants than mastodons, and lived a similar lifestyle. They
also used to live on large, open plains and had flat teeth with ridges for grazing.
Elephants also have similarly shaped teeth. Mammoths mostly ate
flowering plants because they contain more protein and are easier to
digest than grasses. Some species of mammoth also munched on other types
of vegetarian fare, such as cactus leaves, trees, and shrubs.
Physical differences between mammoths and mastodons
Though mammoths and mastodons were both large, hairy, elephant-like
creatures, they did have some differences other than their tooth shape.
Mastodons were a bit shorter and stockier.
Since mammoths tended to live in colder climates, they had fatty humps
where they stored extra nutrients necessary to survive the long, frigid
winters and warmer fur coat. Mammoth tusks curved more while mastodon tusks were straighter and shorter.
Mammoths had a distinctive bump at the top of their skulls while mastodons had flatter heads.
There were multiple species of mammoth (not just the woolly mammoth!)
and mastodon that varied slightly in different aspects of their
appearance — skeletal and dental differences, for example.
A face-to-face comparison of the mammoth (left) and mastodon (right). Image credits: Dantheman9758.
Extinction
Although mastodons evolved earlier than mammoths, both went extinct at a similar time, about 10,000 years ago.
There is some disagreement between experts about what exactly brought
about the demise of these gentle giants — but there are two prevailing
theories.
The first is that they were unable to survive due to increasing temperatures
after the end of the last ice age 12,000 years ago. Glaciers retreated
and sea levels rose, with the warmer temperature causing the environment
to change. Forests grew up where open woodland and grasslands had been.
The arctic tundra and steppe were dominated by flowering plants, but
when the climate became wetter and warmer, they were replaced by
grasses, which were not so nutritious or easy to digest for mammoths.
However, some researchers argue that similar warming periods had
occurred over the past several million years within the ice age without
such disastrous consequences. Therefore, the second theory is that
someone new on the scene played a large role in their demise, more specifically, humans.
There is evidence that Homo erectus ate mammoth meat 1.8 million years ago, but this could be a result of scavenging as opposed to active hunting.
Some sites created in the past 50,000 years in Eastern Europe and
Britain present further evidence that humans hunted mammoths: dwellings
made from mammoth bones and mammoth remains. The spread of more skilled
human hunters around Eurasia and North America coincided with the
disappearance of mammoths and mastodons. However, these creatures lived
across such an enormous area, including remote areas of Siberia, that it
is uncertain if humans with primitive weapons would have been able to
decimate them.
It is more likely that the combination of a changing climate and
human hunters led these giants to their end. The shrinking of suitable
areas to live likely caused many to die out, rendering the remaining
populations more vulnerable.
All in all, mammoths and mastodons lived different lifestyles, but
still looked quite similar, except for some special adaptations for
their diet and climate. They also share similar causes for their demise.
Now, on your next visit to the natural history museum, see if you can
guess if that big, tusked skeleton is a mammoth or mastodon.
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