New Research Finds that Kangaroos are Left-Handed


Nine out of 10 humans may favor their right hands, but—according to a paper that was recently published in Current Biology—most kangaroos have the opposite preference.

Researchers from Russia, Australia, and Tanzania monitored 38 eastern gray kangaroos (Macropus giganteus, the world’s second-largest species), snapping thousands of photos in the process. Every single animal disproportionately relied on its left hand while “grooming the nose, picking a leaf, or bending for a tree branch.” Meanwhile, red kangaroos (Macropus rufus) displayed a similar bias, as the team observed “significantly more left- than right-handed individuals.”

Other marsupials have a different technique. The study also kept tabs on two wild red-necked wallaby (Macropus rufogriseus) populations. These critters “always used their right paw for strength work, like pulling a branch down, but always brought the leaves to their mouth using their left paw,” ecologist Janeane Ingram says.

In nature, preferring one appendage over another is not at all unusual. Many vertebrates have a dominant side—elephants, for example, are either right- or left-tusked. But this is the first proven case of true handedness in non-primate creatures. As Ingram explains, that particular trait was believed to have “evolved primarily in humans” and our closest relatives. Kangaroos and wallabies, though, represent a very different mammalian group.

Given this, we may need to amend long-standing assumptions about how, when, and why righties and lefties first appeared. Like kangaroos, people are built for getting around on two legs—which leads Yegor Malaschichev, a Saint Petersburg State University zoologist, to suspect that bipedal lifestyles are the chief driving force behind the evolution of handedness.

Interestingly, the hopping marsupials show hand-based favoritism to an extent matched only by Homo sapiens (even our fellow apes lack such blatant partiality). “[We] are not alone in the universe,” declares Malaschichev, “we are two—humans and kangaroos.” 

Martin Wittfooth
The Cat Art Show Is Coming Back to Los Angeles in June
Martin Wittfooth
Martin Wittfooth

After dazzling cat and art lovers alike in 2014 and again in 2016, the Cat Art Show is ready to land in Los Angeles for a third time. The June exhibition, dubbed Cat Art Show 3: The Sequel Returns Again, will feature feline-centric works from such artists as Mark Ryden, Ellen von Unwerth, and Marion Peck.

Like past shows, this one will explore cats through a variety of themes and media. “The enigmatic feline has been a source of artistic inspiration for thousands of years,” the show's creator and curator Susan Michals said in a press release. “One moment they can be a best friend, the next, an antagonist. They are the perfect subject matter, and works of art, all by themselves.”

While some artists have chosen straightforward interpretations of the starring subject, others are using cats as a springboard into topics like gender, politics, and social media. The sculpture, paintings, and photographs on display will be available to purchase, with prices ranging from $300 to $150,000.

Over 9000 visitors are expected to stop into the Think Tank Gallery in Los Angeles during the show's run from June 14 to June 24. Tickets to the show normally cost $5, with a portion of the proceeds benefiting a cat charity, and admission will be free for everyone on Wednesday, June 20. Check out a few of the works below.

Man in Garfield mask holding cat.
Tiffany Sage

Painting of kitten.
Brandi Milne

Art work of cat in tree.
Kathy Taselitz

Painting of white cat.
Rose Freymuth-Frazier

A cat with no eyes.
Rich Hardcastle

Painting of a cat on a stool.
Vanessa Stockard

Sculpture of pink cat.
Scott Hove

Painting of cat.
Yael Hoenig
Tony Karumba, AFP/Getty Images
How a Pregnant Rhino Named Victoria Could Save an Entire Subspecies
Sudan, the last male member of the northern white rhino subspecies, while being shipped to Kenya in 2009
Sudan, the last male member of the northern white rhino subspecies, while being shipped to Kenya in 2009
Tony Karumba, AFP/Getty Images

The last male northern white rhino died at a conservancy in Kenya earlier this year, prompting fears that the subspecies was finally done for after decades of heavy poaching. Scientists say there's still hope, though, and they're banking on a pregnant rhino named Victoria at the San Diego Zoo, according to the Associated Press.

Victoria is actually a southern white rhino, but the two subspecies are related. Only two northern white rhinos survive, but neither of the females in Kenya are able to reproduce. Victoria was successfully impregnated through artificial insemination, and if she successfully carries her calf to term in 16 to 18 months, scientists say she might be able to serve as a surrogate mother and propagate the northern white rhino species.

But how would that work if no male northern rhinos survive? As the AP explains, scientists are working to recreate northern white rhino embryos using genetic technology. The San Diego Zoo Institute for Conservation Research has the frozen cell lines of 12 different northern white rhinos, which can be transformed into stem cells—and ultimately, sperm and eggs. The sperm of the last northern white male rhino, Sudan, was also saved before he died.

Scientists have been monitoring six female southern white rhinos at the San Diego Zoo to see if any emerge as likely candidates for surrogacy. However, it's not easy to artificially inseminate a rhino, and there have been few successful births in the past. There's still a fighting chance, though, and scientists ultimately hope they'll be able to build up a herd of five to 15 northern white rhinos over the next few decades.

[h/t Time Magazine]


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