The research
Gground sloths, woolly rhinoceroses, glyptodonts, and short-faced kangaroos: All went the way of the dodo and disappeared from the face of the earth. This is just an example of a large mammal that we don’t have. Of the 57 species of megaherbivores known to have existed 50,000 years ago, only 11 survive. That’s an alarming 81 percent attrition rate.
Large-bodied land mammals averaged 2,200 pounds or more, and today’s remaining megaherbivores include elephants, rhinoceroses, giraffes, and hippos. These animals play important roles in their ecosystems, from dispersing seeds to managing the landscape.
For example, elephants reduce the density of trees and shrubs through their movement and feeding habits. These open spaces provide access to upright animals such as antelope and zebra, while hollows and crevices created by broken branches and felled trees provide habitat for small mammals, insects and fungi.
But these large creatures, unable to hide under logs or move with the agility of a gazelle, were especially susceptible to early humans who wanted to get the most out of every hunt. Because if you’re looking for belly-filling meat and fur to warm your family, the woolly mammoth has a lot more to offer than the rabbit.
Jens-Kristian Svenning, director of the Center for Ecological Dynamics in the New Biosphere at the Danish National Research Foundation at Aarhus University, said: “We know that prehistoric people were particularly focused on hunting large animals. He is also the lead author of a recently published article Cambridge Prisms: Extinction It is argued that human hunting, not climate change, has caused the extinction of most of the megaherbivores over the past 50,000 years.
A woolly mammoth has much more than a rabbit.
To come up with the findings, Svenning and his team analyzed data collected over the past six decades on ancient extinctions, climate and human migration. The case continues a conversation that really began in 1966, when American paleontologist Paul Schultz Martin first proposed his overarching hypothesis—that migrating humans hunted North America’s megafauna from the Pleistocene until its extinction. A few years ago, researchers published an article Nature Likewise, they found that the distribution of megafauna in prehistoric South America in time and space closely matched human demographics, as well as findings of spearheads known as fishtails in the archaeological record.
“It’s a long-term debate,” Svenning says, adding that improvements in research methods and data quality in recent decades have helped us get closer to a definitive answer on how things have gotten worse for megafauna. “We have a much better understanding now than we did in the 1960s,” he says. “What we’ve done is re-examined all of this data, and it allows us to say that we can generally rule out that climate played a major role in this extinction.”
According to the data collected and analyzed by the researchers, where and when the extinctions occurred do not match global patterns of climate change, but they do closely match patterns of human colonization — either around the time we arrived or long after. and locations around the world.
“We conclude that this is one of the strongest, most consistent patterns in ecology,” says Svenning. His team’s findings suggest that these patterns of megafauna extinction began when humans moved out of Africa about 100,000 years ago. Around 50,000 years ago, Eurasia and Australia were colonized by large hunter-gatherers, and the extinction accelerated.
The end of the spear at the business end had such a significant impact on large mammals because they naturally have slow replacement rates. The duration of pregnancy, as well as the maturation process. The 46 species lost in history could not reproduce fast enough to compensate for human deaths.
Felisa Smith, a paleoecologist and professor at the University of New Mexico, believes that human influence on the extinction of megafauna is no longer up for debate. “I think the work of the last few decades has shown convincingly that humans have played a significant role in extinction,” Smith says.
It’s not about accusations, says Svenning. “People who lived a thousand years ago never got the full picture. These things took place on a long time scale and on a large spatial scale, and no one reviewed them; it was hard to see the consequences of whatever people did. Besides, of course, people had to survive as best they could.
Svenning hopes readers will gain a better understanding of the relationships between humans and megafauna and the natural world. Large mammals remain endangered today, with more than half of the species weighing more than 22 pounds listed as vulnerable, threatened, or endangered by the International Union for Conservation of Nature. “When we restore forests, we can’t just think about the trees,” he says. “We have to think about the animals out there.” 
Lead image: maradon 333 / Shutterstock
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