While most mammalian species on earth are easily recognizable for their unique appearances and behavior, none may be quite as distinguishable as those oddities found down under on the continent of Australia. An island nation, entirely secluded from the spread of traditional species found worldwide, Australia is home to a unique form of mammals known for their maternal instincts, classified as "marsupials". The term may encompass many species, however, when the notable pouches of marsupials are often thought of, the species most easily recognized is the jumping species of kangaroos. But new research published this week in the journal PLOS ONE reveals that kangaroo species may not have always had that famous skip in their step.
Published this week in the journal PLOS ONE, researchers from Brown University discovered that a now extinct sub-family of "Sthenurine Kangaroos" had legs much more apt for walking than their descendants, who have made their claim to fame by hopping around on two feet. Weighing up to 485 pounds, researchers claim that the short-faced giants may have found that hopping would be an unachievable mode of transportation.
"At best, they'd have been really clumsy hoppers" lead author of the study, Christine Janis says. But their clumsiness wouldn't have only been a factor in the way they looked as they meandered across desolate plains, it was also a factor that leads researchers to believe they were bipedal walkers much like modern-day humans.
In examining the structural components of sthenurine skeletons found in recent years, comparing their physiological attributes to that of modern kangaroos, the researchers from Brown University were able to find that the ancient species not only had larger hips and knees, but also flared pelvises, all of which is attributed to the ability of being able to support body weight on one leg at a time.
"All of the differences we found were suggestive of putting weight on one foot at a time" Janis says. "Hopping is a tricky gait, and modern kangaroos themselves are near the limit in terms of size" and sthenurine were far larger in their hay day to possessing the hopping talent.
And their walking gait was only part of their oddity. Adding to the ever-growing disillusion that ancient species were not once like their modern-day descendents, the eerie species' of sthenurine kangaroos appear like something out of Alice In Wonderland... only something that'd walk out of a page, rather than jump.