Wild and Sexless

Scientists find snakes give “virgin birth” in the wild for the first time

By | September 17, 2012

image: Wild and Sexless Wikimedia Commons, Tad Arensmeier

Two wild female pit-viper snakes—a copperhead and a cottonmouth—gave birth to fatherless litters, according to researchers at the University of Tulsa in Oklahoma.

The phenomenon of spawning without male contribution—known as parthenogenesis—is common in invertebrates, such as ants. Scientists have also observed it in vertebrates before, including fish, lizards, birds, and snakes, but it’s rare and only seen when animals are captive or when no males are present.

Yet, the two virgin mother snakes were not only wild, but found in populations with males, researchers reported in the study published last week (September 12) in Biology Letters. Further, scientists found the virgins in relatively small collections of pregnant females—just 22 copperheads and 37 cottonmouths—hinting that parthenogenesis may be more common than previously thought.

“I think the frequency is what really shocked us,” Tulsa biologist and lead author Warren Booth told BBC News. “That's quite remarkable for something that has been considered an evolutionary novelty.”

It’s still unclear, however, whether the offspring will survive and reproduce. Fatherless snakes born in captivity have not been viable, but Booth and colleagues recently found a garter snake that produced viable male offspring parthenogenicly.

Some snakes, including pit-vipers, can produce males during parthenogenesis because they have ZW sex determination. In this system, males are homozygous for the sex chromosomes Z (ZZ), while females are heterozygous (ZW). Thus, during parthenogenesis, when a ZW female’s eggs likely fuse to make offspring, there is the possibility of forming ZZ males.

Researchers will know in 2 to 3 years if such males and the females from the pit-vipers’ litters are viable.

“If they cannot survive and reproduce, then this is a reproductive dead-end,” Booth told the BBC. “However, if they are healthy and can reproduce, that opens an entirely new avenue for research.”


Add a Comment

Avatar of: You



Sign In with your LabX Media Group Passport to leave a comment

Not a member? Register Now!

LabX Media Group Passport Logo


Avatar of: Stuart Saunders

Stuart Saunders

Posts: 1457

September 17, 2012

"Wild and sexless"

C'mon, make up your mind.

Avatar of: Eva Amsen

Eva Amsen

Posts: 1457

September 17, 2012

I love the headline on this. :)
The snakes are cool, too.

Thermo Scientific
Thermo Scientific

Popular Now

  1. Sex Differences in the Brain
    Features Sex Differences in the Brain

    How male and female brains diverge is a hotly debated topic, but the study of model organisms points to differences that cannot be ignored.

  2. DNA Repair Pioneers Win Nobel
    Daily News DNA Repair Pioneers Win Nobel

    Tomas Lindahl, Paul Modrich, and Aziz Sancar have won this year’s Nobel Prize in Chemistry for their work elucidating mechanisms of DNA repair.

  3. Antioxidants Facilitate Melanoma Metastasis
    Daily News Antioxidants Facilitate Melanoma Metastasis

    Two compounds boost the ability of melanoma cells to invade other tissues in mice, providing additional evidence that antioxidants can be beneficial to malignant cells as well as healthy ones.

  4. Antiparasite Drug Developers Win Nobel
    Daily News Antiparasite Drug Developers Win Nobel

    William Campbell, Satoshi Omura, and Youyou Tu have won this year’s Nobel Prize in Physiology or Medicine in recognition of their contributions to antiparasitic drug development.

Drummond Scientific
Drummond Scientific
Life Technologies