Virgin Births Happen All the Time
It was Christmas, the turkey had been eaten, and it was terrible.
“It would be pretty hard for the Department [of Agriculture] to be serious and issue an obituary notice for a turkey,” an unnamed department official told the United Press. Nevertheless, news of the turkey’s death hit front pages around the world.
Because it was Christmas. And Graydon the turkey was no ordinary turkey.
He had no father.
He didn’t have an absentee father. He hadn’t been born through artificial insemination or other technological advances. He literally had no father. His mother—one of dozens of turkey hens in an experiment—had been carefully separated from turkey toms by the government agency at a research facility in Beltsville, Maryland, under the watchful eye of embryologist Marlow W. Olsen.
Graydon’s origin had been, in other words, a kind of virgin birth. Or at least a virgin hatching.
He wasn’t the first fatherless turkey to emerge from the more than 28,000 eggs in Olsen’s experiment. There had been about 20 others. But almost all died within an hour or two. No others had lived longer than 22 days.
But Graydon was 254 days and counting on that unlucky Friday, December 13, 1957.
The experiment began almost by accident. Olsen hadn’t wanted to find virgin births. He wanted to figure out why his turkey hens were only half as fertile between January and July. Could their change be related to the male turkeys losing their feathers during that time? To find out, he planned to mate moulting males with his segregated females.
A conscientious researcher, Olsen laid out the first step. “First let’s make sure the eggs now being laid are infertile,” he said.
And some of them weren’t.
So he set about trying to figure out who was fertilizing his turkey eggs. It wasn’t a rogue tom. Some prankster or bumbler on his research team wasn’t swapping eggs. It wasn’t that one of his turkeys was hermaphroditic.
It was that sometimes turkeys have virgin births.
Scientists knew that some animals that normally reproduce sexually could sometimes reproduce asexually. They even had a word for it: parthenogenesis. At the turn of the century, the eccentric biologist Jacques Loeb had persuaded sea urchins to reproduce parthenogenetically by putting (mislabeled!) chemicals on them. By Olsen’s day, biologists had created fatherless frogs and silk worms, too. But they’d never seen it in an animal as complicated as a turkey. And the news that it could happen frequently and naturally was a stunner.
Still, the papers would report, both in his death and in his life, that Graydon had no beauty or majesty about him.
“He appears normal except for the dull witted expression,” Lancaster Farming noted in a front-page photo caption just days before the turkey’s demise. “Owing to bad eyesight for improper nerve coordination, bird consistently undershoots half an inch or more when pecking at food or insects. He eats well, exercises normally, sleeps a good bit.”
In fact, he slept very well. Olsen didn’t trust his department’s turkey pens to keep the bird safe, so he took him to his own home, conveniently located next door to the research center. He was used to this. Twenty months earlier, he had taken home Olie, the first fatherless turkey to live on after hatching. Olie needed constant care and frequent feeding, so Olsen, unmarried and from photos apparently in his 50s, kept him in a brooder next to his bed and fed him by hand. Sadly, Olie died after 22 days, on Easter Sunday 1956, as his digestive system shut down.
Graydon’s digestive system was working just fine when the hunting dogs found him.
“Olsen blames himself,” the United Press reported. “Because he wasn’t on hand to protect his charge. Olsen had gone inside his house shortly before the dogs appeared.”
“When the dogs attacked, [Graydon] didn’t utter a cry,” reported Lancaster Farming. “He died a few hours after the attack. The poult had lived 39 weeks. Now Dr. Olsen must start over.”
But Dr. Olsen had a secret. He didn’t have to start over after all. Within weeks, he announced that another fatherless turkey had lived long enough to reach sexual maturity. And that bird had successfully mated—producing not fatherless turkeys, but grandfatherless ones. By 1962, the Associated Press reported that 40 turkeys born without fathers were “scratching around in their pens at Beltsville.” Researchers now estimate that parthenogenesis usually occurs in 1 percent to 30 percent of unfertilized turkey eggs (with most dying as embryos within a day of incubation). After decades of selective breeding, now about half of unfertilized Beltsville Small White turkey eggs develop embryos.
For years, the lesson of the Beltsville turkeys was essentially similar to that from Loeb’s sea urchins: humans can engineer some creatures to reproduce asexually. That Olsen’s experiment began with a discovery of natural parthenogenesis was largely forgotten.
Then came the sharks.
On December 14, 2001—44 years and one day after Graydon’s death—a female bonnethead (a small hammerhead) in Omaha’s Henry Doorly Zoo gave birth. The shark pup swam around its tank for five hours—and then was attacked by a stingray and died. The mother had been caught near the Florida keys as an immature shark and had lived at the zoo for three and a half years. There were no male sharks around. Some scientists wondered if the shark somehow captured and stored away some male shark’s sperm for more than three years. It seemed impossible.
“Unless it's some kind of virgin birth, I don't know,” zoo director Lee Simmons told reporters. “Without a male, you can't have a birth. But Mother Nature doesn't necessarily abide by the rules. … If we solve this mystery, it's going to make one of the most interesting scientific papers in a long time.”
The birth made the papers. Not just because it was a mystery, but because a virgin birth story always makes the papers at Christmas. And when that interesting scientific paper came out in Biology Letters in 2007, biologists had already suspected the answer: the shark had reproduced parthenogenetically. It really had been a virgin birth.
By then there had been reports of other sharks, too. Weeks after the Omaha birth in 2001, Detroit’s Belle Isle Aquarium had its own announcement. Unlike bonnetheads, the whitespotted bamboo sharks in Detroit lay eggs. Normally, the aquarium had been throwing the eggs out—with only female sharks in the tank, it was unthinkable that any would be fertile. But after reading the news out of Omaha, curator Doug Sweet told his staff to stop.
“I said, ‘Let’s sit on them.’ Well, not literally sit on them—but leave them alone,” he told the Detroit Free Press. The eggs began to hatch.
After that came proof of a parthenogenetic blacktip shark at the Virginia Aquarium.
Then other animals. Nature (in an article published days before Christmas, of course) reported that Komodo dragons in British zoos were reproducing through parthenogenesis. The Sedgwick County Zoo in Wichita, Kansas, said its Komodo dragon was, too.
And snakes. So many snakes. Last year, a reticulated python at the zoo in Louisville, Kentucky, laid 61 eggs. Six of them hatched into happy baby pythons. A yellow-bellied water snake at a Missouri nature center gave birth to litters of fatherless snakes in both 2014 and 2015.
A consensus began to form among biologists and ecologists: Captivity seemed to be the common thread. Perhaps the animals were giving birth parthenogenetically because they had been isolated from males. As one biologist told The New York Times, “It’s a last-resort tactic that animals use when they absolutely can’t find another mate.” Or, to quote Jurassic Park’s Ian Malcolm, “Life, uh, finds a way.”
But there were always those who speculated that maybe the zoos and aquariums were just revealing the animals’ secrets. “How much do we really know about the reproductive habits of bamboo sharks?” Sweet asked the Free Press. “It may be happening out in nature all the time, and we don't know it.”
Which is how the story began to change in 2012. Researchers led by University of Tulsa biologist Warren Booth grabbed dozens of pregnant cottonmouth and copperhead snakes. The snakes had been around males. They could reproduce sexually. But the researchers found that they still reproduced parthenogenetically, too. Asexual reproduction in species that can reproduce sexually or asexually “can no longer be viewed as a rare curiosity outside the mainstream,” the researchers concluded. Since then, more parthenogenic births have been discovered in the wild.
And now there is emerging evidence that they’re not just a last resort. For example, giant prickly stick insect females seem to prefer to reproduce parthenogenetically if they can. And researchers found males among a lizard species that they’d thought was exclusively female and reproduced only parthenogenetically.
In other words: Parthenogenesis may not be all that abnormal as we learn more about animal reproduction. We’re literally talking about the birds and the bees. And we’re learning more all the time.
Fortunately, Christmas comes around every year, and with it updates on “virgin birth” discoveries in the science press. Generally, such articles wisely steer clear of drawing any connection to Jesus’ birth, apart from noting that a woman giving birth to a baby boy through parthenogenesis would still be a miracle requiring the suspension of natural processes.
(Here’s why, with a refresher from sex-ed class: In humans and most mammals, sex is determined by the XY chromosome. Females have XX chromosomes, and males have XY. You have to have a father to provide the Y chromosome. By contrast, turkeys, Komodo dragons, and many of the other animals that can reproduce through parthenogenesis determine sex through the ZW chromosome system. Males have the ZZ chromosome, while females are ZW. So females can give birth to males. Apart from that, a human mother can’t give birth to a parthenogenic daughter either, due to what’s called genomic imprinting—if you don’t have interaction between genes from two parents, an embryo won’t develop to term. Japanese and Korean biologists were able to turn off this imprinting requirement in mice and created the first documented parthenogenic mammals in a lab. But it took a lot of work that wouldn’t happen naturally.)
Certainly it would be a mistake to investigate animal parthenogenesis with an eye to explaining the precise mechanism by which Mary “was found to be pregnant through the Holy Spirit” (Matt. 1:18).
But do we really need to just shrug and assume that there’s no connection at all between virgin births in the animal kingdom and the Virgin Birth of Jesus? After all, the one who made everything (Col. 1:16; John 1:3), including animals who experience virgin births, decided to come into his creation through a Virgin Birth.
“You might say God has created a world where such things are possible,” Oliver Crisp, a theologian at Fuller Seminary, said when I put the question to him. “Maybe it’s not so incredible or beyond belief that the Incarnation would start with a virgin birth. Can we make it less ‘weird’ by pointing to other natural processes? Maybe. But it’s still pretty weird! You still need miraculous chromosomes.”
In fact, Crisp suggested, maybe seeing the virgin births in the animal kingdom shouldn’t make Jesus’ virgin birth seem less weird at all. Maybe it should make it seem even more remarkable. “I don’t want to make a direct line. But might it add to our wonderment and delight that God is doing something in the birth of Christ that he doesn’t even do in other creatures who have ‘virgin births’?”
After all, says Crisp, that’s kind of the point of the Virgin Birth. “Christ didn’t need a Virgin Birth to make the Incarnation possible,” he said. “The Virgin Birth is a signal to us that Christ is marked off from the rest of humanity as more than a mere human. Elsewhere in Scripture, God performs signs and wonders around births to underline the fact that this is something we need to pay attention to.” Isaac. Jacob and Esau. John the Baptist. In each case, miraculous conceptions are “signposts that display God’s purpose in the salvation of the world. The miracles tell us to sit up and pay attention.”
Ted Olsen (@tedolsen) is editor of The Behemoth. So far as he knows, he is unrelated to the poultry researcher Marlow Olsen. But stranger things have happened.
- Editor's Note from December 24, 2015
Issue 38: Virgin births in the animal kingdom, a modern Wise Man’s journey, and the womanhood of creation. /
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What I’ve learned as an amateur astronomer. /
- Why Mary Is So Blessed
An Orthodox theologian describes how the Mother of God is what all creation was created to be. /
“We hear and sing / The customary carols” /
- Wonder on the Web
Issue 38: Links to amazing stuff.