Ancient giant kangaroos could have hopped despite their huge size

Even Giant Kangaroos Might Have Hopped, Study Suggests

A recent analysis of fossilized bones suggests that even the giant kangaroos that roamed Australia thousands of years ago might have had the ability to hop, contrary to previous beliefs.

During the Pleistocene era, some kangaroo species, particularly the sthenurines, were significantly larger and heavier than modern-day kangaroos. These bulky creatures were thought to be incapable of hopping and were believed to have only walked on their hind legs.

Researcher Megan Jones from the University of Manchester explains, “Sthenurines are what most people are talking about when they discuss giant kangaroos. They were incredibly unique with short, boxy skulls and a single toe on each foot. While today’s largest kangaroo species, like the red kangaroo, weigh around 90 kilograms, the largest sthenurine weighed approximately 250 kilograms.”

The largest of these giant kangaroos was Procoptodon goliah, standing at an impressive height of 2 meters before going extinct around 40,000 years ago.

To determine the biomechanics of these ancient kangaroos, Jones and her team compiled bone measurements from various macropod species, including both extant and extinct kangaroos, wallabies, and other related species.

By analyzing the leg bones such as the femur, tibia, and calcaneus, and considering factors like body mass, the researchers were able to estimate the size of the tendons and their ability to withstand forces generated during hopping.

Jones explains, “The Achilles tendon in modern kangaroos is at risk of breaking, but it’s a crucial feature that allows them to store elastic energy for the next hop. Scaling up a modern kangaroo would pose challenges, but ancient kangaroos had unique adaptations that enabled them to hop more efficiently.”

While hopping may not have been the primary mode of locomotion for giant kangaroos, the study suggests that they might have used it for short bursts of speed.

Benjamin Kear from Upsala University in Sweden comments, “The study adds to the understanding of kangaroo locomotion, showcasing the adaptability of their gait over millions of years, which has contributed to their ecological success.”

Today, kangaroos exhibit a range of locomotion methods, including hopping, walking with the tail as a fifth limb, and even bipedal movements in tree kangaroos.