Matthew James Ferguson/Shutterstock
During the late Pleistocene epoch (126,000–11,700 years ago), the world witnessed a wave of megafaunal extinctions—species weighing roughly 110 pounds or more vanished as the planet’s climate shifted dramatically. Many of the megafauna that thrived in that era did not survive into the Holocene.
Extinction timelines varied by continent. In North America, the disappearance of large mammals such as woolly mammoths and saber‑toothed cats began around 12,900 years ago. In Australia, over 90 % of the continent’s large‑animal fauna went extinct between 65,000 and 40,000 years ago, with kangaroos—including the towering Procoptodon goliah, which stood over 6 ft tall and weighed more than 440 lb—accounting for more than half of those losses.
Scientists have long debated the causes of these extinctions. While climate change and the resulting loss of food sources are commonly cited, the role of early human hunters has been less clear. A recent analysis of hundreds of kangaroo teeth, both fossilized and modern, suggests that humans played a larger part in the demise of Australia’s kangaroos than previously believed.
Today, Australia is home to four kangaroo species: the red, eastern grey, western grey, and antilopine kangaroo. Once far more diverse, the kangaroo lineage suffered heavy losses in the late Pleistocene. Climate change alone does not fully explain these reductions. A January 2025 paper published in Science overturns that narrative, showing that kangaroos had already survived major climatic shifts and that human predation likely tipped the balance.
The study examined the teeth of 937 kangaroos—including 12 extinct and 16 modern species—under the guidance of paleontologist Samuel Arman from the Museum and Art Gallery of the Northern Territory. By assessing dental wear patterns, the team reconstructed the animals’ diets and found evidence that extinct kangaroos were generalist grazers, not limited to tough vegetation as previously thought. This dietary flexibility implies they were well‑adapted to changing climates.
These findings indicate that the extinction of giant kangaroos coincided with the arrival of human hunters between 70,000 and 50,000 years ago, a period when humans were becoming increasingly efficient predators.
Matthew James Ferguson/Shutterstock
Arman’s research, coupled with earlier studies—such as a 2010 PNAS paper that linked human arrival to southwestern Australian extinctions—strengthens the argument that anthropogenic pressures were decisive. Although climate change and fire regimes may have played supporting roles, the generalist diet of these kangaroos suggests they were not inherently vulnerable to environmental shifts alone.
Not all experts agree, however. Paleontologist Larisa DeSantis of Vanderbilt University, who was not involved in the study, cautioned that examining a single time slice may underestimate climate’s influence. Nonetheless, the mounting evidence points to a complex interplay between humans and the environment in shaping Australia’s megafaunal history.
