Out of all of the prehistoric animals that have roamed the planet, the woolly mammoth is perhaps one of the most endearing. This is largely because woolly mammoths are incredibly similar to modern elephants, and they went extinct only a few thousand years ago - meaning that they coexisted with modern humans. They also lived during the Ice Age, a period that seems alien to modern people because it was so different from the conditions we live in.
Thanks to the huge amount of study that surrounds these creatures, plenty of interesting woolly mammoth facts have been discovered in the last few decades. This information helps explain what happened to the woolly mammoth, how it lived, and the evolutionary adaptations it developed to live in harsh environments.
A Mammoth Bone Pit In Mexico City Suggests Some Of Them Got Stuck In The Mud
The remains of more than 60 mammoths were discovered in Mexico City by the National Institute of Anthropology and History in May 2020. The bones are estimated to be about 15,000 to 20,000 years old, and were uncovered near previously excavated human-built traps. According to The Associated Press, the site was once a shallow lake that would have been appealing for the species because of the available grasses and reeds. There, "archeologists are facing a surfeit of mammoths, almost too many to ever excavate."
Though the previously uncovered remains apparently perished at the hands of human hunters, the 60 new fossils did not have any of the distinct markings that would suggest human involvement. Instead, they likely "got stuck in the mud of the ancient lake and died, or were eaten by other animals."
A Number Of Factors Likely Led To Their Demise, Including Climate ChangePhoto: National Park Service
Woolly mammoths were common throughout North America and Siberia for hundreds of thousands of years. The giant creatures began to die out around 20,000 years ago, however, and are believed to have become extinct 4,000 years ago when the last of a few isolated groups disappeared.
No one reason is to blame for their extinction. Although humans lived alongside the animals for thousands of years, people likely played a significant part in mammoths' demise due to hunting. Yet climate change may have been the defining factor that wiped out the mammoths.
In 2021, scientists who studied the remains of a 28-year-old woolly mammoth from Alaska they named Kik (after the nearby Kikiakrorak River) found that he had probably died of starvation, possibly due to drought or injury. The researchers, using one of the mammoth's tusks to study elements that built up over time, determined that he had traveled 43,500 miles all around Alaska during his lifetime (for perspective, that's enough to walk around the Earth twice). At about age 16, when he was on his own and no longer part of a herd, his movements changed, and in the last 18 months of his life he was confined to a small area. Climate change, the scientists believe, might have shrunk the habitat available to the mammoth, or made him more vulnerable to human hunters.
Genetic Defects May Have Led To Their Extinction
Just before the woolly mammoths went extinct they went into what has been described as a "genomic meltdown." As their populations diminished rapidly and only small groups survived, their gene diversity was dramatically reduced. This led to significant mutations in their DNA; these genetic defects would have caused the animals to lose their sense of smell and change their social behavior.
"There was this huge excess of what looked like bad mutations in the genome of the mammoth," said Dr. Rebekah Rogers, a researcher from the University of California, Berkeley. "We found these bad mutations were accumulating in the mammoth genome right before they went extinct."
In 2020, researchers with the University of Chicago published a study in which they successfully resurrected mammoth genes from the last known population of the species on Wrangel Island in the Arctic Ocean. The goal was "to test whether their mutations actually were damaging," said lead author and assistant professor of biological sciences Vincent Lynch, since most mutations have little to no actual effect.
The study compared the Wrangel Island mammoth genes to that of similar populations such as Asian elephants and two other mammoth species. Using the synthesized altered genes of the Wrangel Island mammoths, researchers were able to visually see how they interacted with other molecules.
The results of the 2020 study complement Rogers's theory. Lynch concluded that "the last mammoths may have been pretty sick and unable to smell flowers [which they ate for food], so that’s just sad."
Mammoth Fossils Overwhelmingly Belong To Males
One of the most puzzling things about the woolly mammoth is that the vast majority of fossils found are from male mammoths. In most other species, the fossil record would show an even amount of both sexes as long as there was a roughly equal number of each sex.
“We were very surprised because there was no reason to expect a sex bias in the fossil record,” said study author Patricia Pecnerova. With 69% of all fossils found belonging to male mammoths, researchers have worked hard to find a compelling explanation.