Five Shocking Animal Hybrids That Truly Exist in Nature, From Narlugas to Grolar Bears to Coywolves

For well over a month, the internet has been buzzing with rumors surrounding a mysteriously pregnant stingray and the idea that she might be incubating a type of never-before-seen offspring: shark-stingray hybrid babies.

In February, an ultrasound of a female round stingray named Charlotte, who lives at an aquarium in Hendersonville, North Carolina, revealed she was carrying up to four pups. This might have been a routine discovery if it weren’t for one shocking detail—she doesn’t share her enclosure with any other ray. Instead, Charlotte is accompanied by two male sharks, prompting the hybrid speculation.

But in reality, scientists say a shark couldn’t breed with a stingray—their anatomies are completely different. In the case of Charlotte, then, her pregnancy can most likely be explained by parthenogenesis, a type of asexual reproduction akin to cloning that’s performed by some fish, reptiles and birds.

While we’re not likely to see shark-ray hybrids anytime soon (or, probably, ever), some truly spectacular hybrid animals already exist in the world. Many have happened serendipitously in captivity, such as the liger, the massive offspring of a male lion and female tiger. And others have been intentionally created by humans—from the beefalo, a blend of cattle and buffalo bred for meat production, to the ancient kunga, a cross between a female donkey and a male Syrian wild ass that may have been a status symbol in Mesopotamia 4,500 years ago.

Occasionally, though, hybrid animals appear in the wild—sometimes as a chance occurrence, and sometimes due to interference from climate change. As humans, even we are the result of hybridization, as all people of non-African descent derive about 1 to 4 percent of their DNA from Neanderthals, while African people have about 0.5 percent Neanderthal DNA.

Here are five other crosses between animals that have appeared in nature.

Narlugas

When an Inuit subsistence hunter captured a strange-looking whale in Greenland in the 1980s, he saved its unusual skull. The puzzling bone didn’t precisely resemble any known cetacean—its teeth were spiraling in odd directions, and along its top jaw were tiny “tusks” that stuck out almost horizontally. What’s more, when the hunter killed this creature, he also killed two others that looked like it, with solid gray skin, narwhal-like tails and beluga-like flippers.

Scientists long suspected these animals were hybrids, and in 2019, researchers took a DNA sample from the bone and came to a conclusion: The skull belonged to a first-generation narluga—a cross between a narwhal and a beluga whale.

So far, the skull and the hunting anecdote are the only evidence of narlugas in the wild—not nearly enough to designate the hybrid as its own species. But in recent years, scientists have been speculating the phenomenon could happen again: In 2016, a narwhal in the St. Lawrence River in Canada started swimming among a pod of belugas. They seemingly “adopted” the lone narwhal, even though the two species don’t typically interact.

In 2022, when the narwhal was 12 years old and reaching sexual maturity, some began to suggest the out-of-place animal might mate with a beluga and produce narluga calves. If the narwhal fits in well enough with the male belugas, he might join an alliance with them and collectively court female whales.

Scientists don’t know if a baby narluga would grow up to be fertile, but if one happens to be born in the St. Lawrence River, it could help solve that mystery. And, for now, scientists can only wonder how many narlugas might be out there, swimming the oceans undetected.

“What are the odds that someone would find the only hybrid ever and keep it on his shed, and that someone else would find that and send it to a museum?” Eline Lorenzen, who studied the skull, told the Atlantic’s Ed Yong in 2019. “There must be more. But maybe not! We have no idea.”

Grolar bears

A mix between a polar bear and a grizzly, a grolar bear (sometimes called a pizzly bear) is a rare occurrence aided by climate change. The two kinds of bears sometimes intermingle—usually in an aggressive way—but as the planet warms, their ranges have begun to overlap more. Grizzlies might venture to the warming north as humans settle in their more southern habitats, and some polar bears might foray to the south for food in response to melting sea ice, which they ordinarily need for hunting seals.

In 2006, a hunter shot a white and speckled brown bear in northern Canada that had the humped back and long claws of a grizzly. DNA analysis discovered it was the offspring of both a grizzly bear and a polar bear—the first known grolar bear specimen. Since then, scientists have identified more of the hybrid animals, and a 2017 study recorded four hybrid offspring of a female polar bear and a male grizzly. These creatures then mated with grizzly bears, creating another generation of bears with both polar and grizzly DNA.

Now, some scientists have expressed concerns that polar bears could get bred out of existence if they keep interacting with grizzlies. Others say that in a distant, warmer future, perhaps no bears will be able to survive at high latitudes. But on the flip side, some suggest the hybrid offspring might be more equipped to live in a world altered by climate change.

“Apex predators help stabilize ecosystems, and looking forward, I really hope the Arctic still has a polar bear,” Larisa DeSantis, a paleontologist at Vanderbilt University, told Live Science’s Ben Turner in 2021. “But, with that all being said, could the pizzly allow for bears to continue to exist in intermediate regions of the Arctic? Possibly, yes. That’s why we need to continue to study them.”

Golden-crowned manakins

The Amazon rainforest is home to several kinds of little green birds that could fit in the palm of your hand. Males have a splash of color atop their heads, some sporting feathers in iridescent blue or pink hues, while others are snow-white. But on very rare occasions, people have spotted another kind of bird—one with a brilliant yellow crown. Though scientists identified the species in 1957, it was 45 years before they found one again.

They dubbed these elusive creatures golden-crowned manakins, and their lighter-colored counterparts are opal-crowned and snow-capped manakins. Scientists wondered if the little creatures with yellow head feathers were a hybrid of the other two, but they couldn’t fathom how two birds with essentially white feathers could breed to create a new color.

In 2017, scientists sequenced much of the golden-crowned manakin’s genome and discovered it derived about 80 percent of its DNA from the opal-crowned manakin and about 20 percent from the snow-capped manakin. This discovery made it the first known hybrid bird species in the Amazon.

For both of the purebred species, their pale feathers get their color not from pigment, but from a unique structure. The golden-crowned manakins, on the other hand, actually have yellow pigment in their feathers—organic coloring agents called carotenoids, which the birds get from their diets.

During the last ice age, researchers say the golden-crowned manakin’s habitat became cordoned off from that of the other little birds, separated by wide rivers. This allowed the yellow-capped creatures to evolve independently. Scientists suggest the golden head feathers were rewarded by natural selection, as females chose the most vibrantly colored hybrids to reproduce with. Perhaps the first golden-crowned manakins were not so vivid but had duller yellow crowns that more closely resembled those of their ancestors.

Dolphin hybrids

When it comes to reproduction, dolphins may be among the least discriminatory creatures on the planet—frequently mating with cetaceans of other species, dolphins seem especially “open-minded,” wrote the Washington Post’s Jason Bittel in 2019.

In a 2016 study, researchers documented 20 cases of dolphin hybridization, and only seven of them occurred in captivity. These interspecies dalliances represented 18 unique pairings of species—and most of these were not closely related. Only two of the couplings belonged to the same genus.

In fact, dolphins appear to be so flexible about which species they breed with, that researchers suggest hybrid dolphins might be far more numerous than we might assume. And from just a quick glimpse of a dolphin in the wild, it might not be easy to tell that it’s a hybrid. “In general, it is likely that many living hybrids seen in the wild are not recognized as such,” per the paper.

But a few notable individuals have made headlines: Scientists glimpsed a rare hybrid of a rough-toothed dolphin and melon-headed whale near Hawaii in 2018. And a creature that appeared to be part bottlenose and part striped dolphin was spotted off the coast of Falmouth, England, last August and thought to be a first-ever sighting for the United Kingdom.

These hybrid individuals don’t represent new species—the hybrids would have to be more widespread and breed among themselves to earn that classification. But they do signal how flexible breeding dolphins can be—and scientists suggest this could indicate similarities in cetacean DNA, as their species only diversified within the last ten million years.

Eastern coyotes or 'coywolves'

Currently, a legion of hybrid canines is spreading across the Eastern United States. These creatures—often called coywolves—are crosses between coyotes and wolves, and they even have domestic dog DNA. Also referred to as Eastern coyotes, these animals have been around for nearly a century, but their population has really begun to explode in recent decades.

Wolves were exterminated from most of the Northeast by the mid-1800s, and their numbers were at record lows around the Great Lakes by the early 20th century, per the National Park Service. Fewer wolves meant fewer potential mates, so they likely turned to coyotes to breed.

Now, Eastern coyotes are bigger than their western counterparts and have been able to successfully inhabit the northeastern U.S.—even dwelling in cities and spreading to the south. Roland Kays, an ecologist at North Carolina State University, told the Economist in 2015 that coywolves might number in the millions.

The hybrid animals also seem to be taking on increasingly wolf-like characteristics. They are becoming larger and more adaptable, and the canines are now poised to fill the role of an apex predator on the East Coast.

Officially, Eastern coyotes are one of 19 coyote subspecies, and scientists disagree on whether or not coywolves should be designated as a species of their own. According to analysis by research scientist Jonathan Way of Clark University, up to 40 percent of these animals’ DNA could come from canines other than coyotes. But Kays argued that coywolves are “not a thing” in an article for the Conversation in 2015. “In other words, there is no single new genetic entity that should be considered a unique species,” he wrote.

No matter what you call them, scientists say coywolves are here to stay. And following the proper measures, humans can peacefully coexist with the hybrid animals.

“I know a lot of Vermonters love to hate the coyote. But I think that it really has an important niche,” Kim Royar, a biologist with Vermont Fish and Wildlife, told Vermont Public in 2013. “It’ll be here for the long term, and we really just need to learn how to live with this animal.”

Carlyn Kranking | | READ MORE

Carlyn Kranking is the assistant web editor for science and innovation.