Mongrels

Meet Kekaimalu the Wholphin. Half whale, half dolphin.


Also, annoyingly, it has dual citizenship, so it can move to Canada.

Technically, the Wholphin is the offspring of a female bottlenose dolphin and a male false killer whale, which is technically another dolphin. (As is the true killer whale.) But remarkably, she is not only a hybrid of two different species, but different genera. What’s more, she’s no mule; Kekaimalu has given birth to three healthy calves in her home in Sea Life Park in Hawaii. She is the average of her parents’ sizes and colors, being larger and darker than the average bottlenose dolphin

and smaller and lighter than the average false killer whale.

In addition, she has an intermediate number of teeth: Bottlenoses have 88 teeth, false killers have 44; the Wholphin has 66. So, the best of both worlds, right? Not so fast. Consider that Kekaimulu has only ever lived in captivity, outside of the bloody struggle of competition, and it’s unlikely she’d survive in the wild ocean. What’s more, almost all the hybrids you hear about — the liger, the mule, the zorse and the zonkey — occur in captivity, implying that hybridization between different genera is a fluke, and often an evolutionary dead end. But recently, there’s been an epidemic of hybridization in the wild, resulting in chimaera of unique proportions: the pizzly bear, a hybrid of the polar and grizzly, and the narluga, a cross of narwhal and beluga whale. Cool, right? Like a griffin, or a pegasus, or a Wuzzle? While cross-genera hybridization sounds as exciting as something out of The Island of Dr. Moreau, what it bodes for the future of the environment is just as ultimately tragic.

What’s the problem with hybridization? Many evolutionists have suggested that hybridization has given rise to adaptive radiation in just the same way as natural selection. Take, for example, a flower that has adapted to live in the high Alpine part of a mountain — let’s call it the Spotted Jennybottom. And it has a close cousin adapted to live in the wet ravines at the feet of the same mountain: the Blue-Flanked Jennybottom. During a particularly warm summer during which there are also very few Blue-Flanked Jennybottoms, a bee goes off in search of nectar in the high part of the mountain, pollinating a Spotted with a Blue-Flanked. And through sheer chance, the seeds end up rolling halfway down the mountain. And they’re not infertile! And they are a complete average of their parents, able to tolerate the mid-range temperatures and semi-rocky soils of the mountain slopes! Behold, the rise of a third species, the Spanked Jennybottom!


I will always remember the smell of the warm spring air, when the Spanked Jennybottoms were in bloom.

The only problem is that the Spanked Jennybottom is just as likely to have the worst of both worlds as the best. The lowland bees aren’t likely to travel up the mountain to it again, unless in desperation. Or maybe it tolerates only the cold temperatures of the alpine zone and the clay soils of the ravines, making it unsuitable for either. First- and second-generation hybrids can be very robust and have superb adaptations for surviving in the medium, a phenomenon called “hybrid vigor.” (Those of you with mutt dogs know your pooch can think circles around those dopey purebred Afghans.) But while inbreeding can cause major defects, so can outbreeding, and over time the hybrid lines have a tendency to weaken. In particular, the hybrid animals lose the ability to live in the extreme, which is essential to the survival of a species during disastrous times; the Spanked Jennybottom would be wiped off the face of the Earth after another particularly hot or wet summer. While human beings have been hybridizing animals for thousands of years to find the best qualities, Mother Nature hates a mongrel. Wholphins, if they exist in the wild — and there have been sightings — are likely to be too large and slow for the dolphins, too small to hunt with the whales. Narlugas, which lack the tusks of their narwhal parents, are at a distinct disadvantage when it comes to mating, as they have no way to spar with other males, or show off to females. Pizzly bears are poor swimmers, unlike their Ursus maritimus mothers, and are too brown to camouflage in the snow. In a world of natural selection, where a centimeter’s change in beak size can be the difference between survival and starvation, the burdens of hybridization can be too heavy for an animal to bear.


“It’s pretty much my favorite animal. It’s like a lion and a tiger mixed… bred for its skills in magic.”

And sometimes, the opposite is true. Sometimes, the Spanked Jennybottom takes over the whole dang mountain. When the red wolf of the Southwestern U.S. was nearly exterminated in the mid-20th century, the last few survivors took to mating with coyotes because, well, they were available and the wolves were horny and lonely. The coy-wolves, larger than the coyotes and certainly more abundant than pure wolves, took over. But there are almost no genetically pure red wolves left; the species is essentially extinct, except where it’s sewn into the DNA in spliced patches of genomic yarn. As a result of hybridization, biodiversity has lost out.

Then there’s the other great hybrid success story: white folks. If you are of European or Asian ancestry, congratulations: you are between 1% and 4% Neanderthal. It turns out that our Cro-Magnon forebears were boffing their big-browed cousins after they were a distinct species split off from the African line. And if you want to see what hybridization can do to biodiversity, just look what happened to the Neanderthals. Evolutionarily speaking, it was a one-night stand from which they never recovered. We loved ’em, left ’em with a fake number in the morning, and never heard from them again.


Why won’t he call? It’s been two weeks, and my period’s late.

Those Homo sapien/Homo neanderthalensis hybrids may have been the product of the same motivator as what has produced the coy-wolf, the narluga, and the pizzly: sheer sexual desperation. (See photo above.) In a new study published in December, researchers have found at least six hybrids that have been found in the wilderness of the Arctic, and give 34 different potential hybrids that can occur. These hybrids have never been seen before in human history, and seem to be instigated by two factors: their parent species’ numbers are diminishing, and the melting Arctic sea ice is allowing marine animals who were previously separated to freely mingle. In other words, the combination of overhunting and global warming is leading to increased hybridization: ringed seals and ribbon seals, bowhead whales and right whales, and more, all creatures of vastly different chromosomes and lifestyles. At best, the hybrids will be sterile or simply unfit, and only one generation’s time will be wasted. At worst, they’ll be fertile and too fit, wrecking havoc on genetic code that millions of years of evolution has carefully perfected and ultimately weakening the species’ constitution. Bowhead whales can live over 200 years; if a bowright whale is somehow a hit with the lady whales instead of a social pariah, he could sire almost a hundred calves in his lifetime, all carrying Right Whale adaptations that will dilute the Bowhead genes.

Add to the confusion the legal protection status of such hybrids — red wolves are protected, coyotes are not — and you can see how unlucky it can be to be a mongrel. Hybridization is a last-ditch effort by a species to survive by splicing itself to another, the natural version of artificial selection. But new species born out of one type of disaster are often unequipped for other disasters; the centrist path, genetically, leaves you vulnerable to the extremes of chance and climate. The tragedy of the wholphin is that, born of two worlds, it may be too unique for ours.

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About quantumbiologist

Christian Drake, AKA The Quantum Biologist, is a naturalist and poet formerly of Albuquerque, NM and currently living deep in the backwoods of the Connecticut Berkshires. He has worked in aquariums and planetariums, national parks and urban forests. When not birding or turning over rocks to find weird bugs, he enjoys rockabilly music, gourmet cooking, playing harmonica and writing dirty haiku. View all posts by quantumbiologist

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