Friday 8 March 2013

Top 5 Virgin Births with Unlucky Deaths



Virgin births are rightly met with curiosity and awe, but for some, ‘miraculous’ beginnings have met with ill-fated ends.  Producing a virgin birth is difficult process. The first part – ignoring males – is easy. But the mother’s body then has to subvert the egg-making process, tricking developing eggs to think they’ve been fertilised.  Without fresh genetic material, developing embryos can suffer the effects of inbreeding, so most don’t survive. Which makes it such a shame that when they do, they have sometimes met with premature endings. Here are my Top 5 Unlucky Deaths for Virgin Births….

At 5: Griller killer

Leiolepis triploida is an all-female, asexually
 reproducing species  (courtesy of Jesse Grismer)
In 2010, reptile scientist Ngo Van Tri, spotted what he thought was a new all-female species of lizard – in the tanks of rural Vietnamese diners. Excited, he contacted US herpetologists Lee and Jesse Grismer who jumped on a plane to Hanoi, then completed a perilous two-day motorcycle trip to the restaurant where the owner had promised to save sixty lizards on their behalf. Save them he did, but grilled them first. When the duo arrived, the crispy creatures were being shared with customers.

Undeterred, the Grismers and Van Tri enlisted the help of local children to catch new specimens, subsequently confirming the lizard, Leiolepis ngovantrii, a new female-only species that reproduces by parthenogenesis – where eggs develop without fertilisation.  Jess Grismer, who works at the University of Kansas, admits he did succumb to a taste test but won’t be eating them again in a hurry. “They tasted horrible,” he said.

At 4: The Deathray

(Image: Henry Doorly Zoo)
Just over a decade ago, aquarists at Nebraska’s Henry Doorly Zoo noticed something unusual. A baby bonnethead shark (Sphyrna tiburo) had appeared overnight in one of their tanks. The tank housed three female sharks but no males. The females had been caught young, before they were sexually mature and genetic tests confirmed that the baby had a mother but no father. “It was the first confirmed virgin birthin sharks,” says Demian Chapman of Stonybrook University in New York who paternity tested the pup.

Unfortunately we’ll never know if the shark would have grown up and reproduced normally, as it was killed a few days after its birth by a grumpy stingray that didn’t feel like sharing its tank. But it alerted aquarists to watch out for virgin births, and to date, the phenomenon has been confirmed in three additional shark species.



At 3: Canine calamity

(Image: SliceofChic)
Ironic that turkeys, the birds most frequently eaten to celebrate the world’s most famous virgin birth, can themselves produce virgin births. In the 1950s, researchers at the Beltsville Agricultural Research Center in Maryland noticed that unfertilised eggs from Beltsville Small White turkeys sometimes began to develop on their own. The discovery marked the beginning of a selective breeding program, aiming to increase the frequency of parthenogenesis in turkeys. Lead researcher, Dr M. W. Olsen carefully transferred the first turkey virgin birth from the research farm to his basement for safekeeping…. but shortly after it was attacked and killed by his dog.

Undeterred, Olsen continued his breeding experiments, creating a parthenogenetic-prone strain of turkey. Female turkeys, which carry mixed sex chromosomes, produce only male virgin births. Anecdotal reports of virgin births in quails and chickens have since been noted, but turkeys remain the only confirmed bird species capable of parthenogenesis.



At 2: Death by diner

(White-spotted bamboo shark at Newport Aquarium)
Some sharks give birth to live young, others lay egg cases. One female white-spotted bamboo shark (Chiloscyllium plagiosum), caught whilst young and housed without males, laid many egg cases during her 6 years in captivity, but they were presumed infertile and discarded. Then keepers at Detroit’s Belle Isle Aquarium heard about the bonnethead virgin birth, and decided to keep the eggs to see what happened. In 2002, 3 sharks emerged from 9 eggs, of which 2 survived and were confirmed bona fide virgin births.

We know the shark duo survived for at least 5 years, until the aquarium closed and its inhabitants were rehomed. Ominously, the sharks were sold to a seafood restaurant, where they were put on display. But over time, their whereabouts were lost. “No one knows what happened to them,” says shark geneticist Demian Chapman. A loss to science, their legacy remains – their debut proved that female sharks can produce multiple, viable offspring through parthenogenesis.

At 1: A Cross Ending


Christ the Pantocrator
by Metropolitcan Jovan Zograf (1384)

Surely the most famous virgin birth is that of bearded miracle-worker, Jesus of Nazareth. Reports suggest that baby Jesus had a mother, called Mary, but that his father was a supreme metaphysical being called God.

Unlike the Vietnamese lizards, the only grilling Jesus got was at the hands of Pontius Pilate; shortly before he was nailed to a big cross and died. In the absence of any DNA samples from Jesus, scientists have been unable to perform the genetic tests necessary to verify his virgin birth status.





Virgin births have been genetically confirmed in many different species including certain sharks, snakes, komodo dragons and turkeys. There are also many female-only strains of fish, lizard and frog. If you'd like to find out more, have a look at my long read, Clone alone: Who Needs Sex.