 Flora the Komodo dragon
walks around her enclosure at Chester Zoo, Chester, England, Monday Dec.
18, 2006. In an evolutionary twist, Flora has managed to become pregnant
all on her own without any male help. Other reptile species reproduce
asexually in a process known as parthenogenesis. But Flora's virginal
conception, and that of another Komodo dragon earlier this year at the
London Zoo, are the first time it has been documented in a Komodo dragon.
[AP Photo]
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Chester, England - In an evolutionary twist, Flora the Komodo dragon has
managed to become pregnant all on her own without any male help. She is carrying
seven baby Komodo dragons.
"We were blown away when we realized what she'd done," said Kevin Buley, a
reptile expert at Flora's home at the Chester Zoo in this town in northern
England. "But we certainly won't be naming any of the hatchlings Jesus."
Other reptile species reproduce asexually in a process known as
parthenogenesis. But Flora's virginal conception, and that of another Komodo
dragon earlier this year at the London Zoo, are the first time it has been
documented in a Komodo dragon.
The reptiles, renowned for their intelligence, are native to Indonesia. They
are the world's largest lizards and have no natural predators -- making
them on par with sharks and lions at the pinnacle of the animal kingdom.
The cases of Flora and the London lizard, Sungai, are described in a paper
published Thursday in Nature.
Parthenogenesis is a process in which eggs become embryos without male
fertilization. It has been seen in about 70 species, including snakes and
lizards. Scientists are unsure whether female Komodo dragons have always had
this latent ability to reproduce or if this is a new evolutionary development.
At 8 years old, Flora -- whom Buley describes as "demure" -- is
sexually mature. Having been raised in captivity, she has never been exposed to
a male Komodo dragon. She lives with her younger sister, Nessie.
Flora's keepers first became suspicious in May, when she laid 25 eggs.
Though it's not uncommon for female dragons to lay eggs without mating, such
eggs are not usually fertilized. As a precaution, they were placed in an
incubator. About half of Flora's eggs looked like real eggs -- they were
very white and had solid shells.
When three of them collapsed, scientists took a closer look.
"We saw blood vessels and a small embryo," said Buley, one of the Nature
study's authors. "And we knew immediately that Flora had fertilized the eggs
herself."
They then sent the collapsed eggs, along with tissue samples from Flora,
Nessie, and a male Komodo dragon, to a laboratory in nearby Liverpool that
conducted genetic testing to determine the eggs' parentage. Results showed that
although the baby Komodo dragons are not exact Flora clones, their DNA could not
have come from any other dragon.
At the London Zoo, Sungai gave birth to four dragon hatchlings in April
through self-fertilization. After their births, Sungai went on to mate normally
with a male dragon, producing another baby dragon.
"Komodo dragons seem to be able to switch ways of reproducing to deal with a
shortage of suitable boyfriends," said Dr. Rick Shine, a professor of
evolutionary biology at the University of Sydney, Australia. Shine was not
involved with the Nature paper. In contrast, other lizard species that reproduce
asexually cannot mate normally.
That might give Komodos a distinct survival edge. Only about 4,000 dragons
remain in the wild, of which 1,000 are female. Concerns about dwindling Komodo
dragon populations might be allayed by Flora and Sungai's recent self-induced
motherhood.
"If female dragons can on occasion help out by virgin births, more power to
them," said Trooper Walsh, a US-based Komodo dragon expert, who was not
connected to the study. "Komodo dragons are the ultimate survivors," said Walsh.
"This is just another way this species can adapt to its surroundings."
The discovery that Komodo dragons can reproduce asexually also has major
implications for how they will be bred in captivity in the future.
Experts are also keen to find out how prevalent virgin births are in the
wild.
"It's baffling why a species starts doing this," said Kevin de Queiroz, a
research zoologist at the Smithsonian Museum of Natural History in Washington,
who was not involved with the paper. "It would be helpful to know how often this
happens and what the mechanism is that allows them do that."
In the meantime, Buley and his colleagues at the Chester Zoo are eagerly
anticipating the hatching of Flora's remaining eggs. A Christmas arrival, Buley
says, would probably be on the early side, since the baby dragons are not
technically due until January.