In the Northern Territory of Australia, Darwin’s suburbs are being invaded by an introduced species of Gecko which is totally female. NT Minister for the Environment, Marion Scrymgour, said it was disquieting to find the Mourning Gecko in a Darwin suburb, because another introduced gecko, the Asian House Gecko Hemidactylus frenatus has already successfully invaded Darwin.
“Historically, Darwin’s common house gecko was a native species but this has been mostly displaced by the Asian House Gecko which is thought to have been introduced during the early days of European settlement at Port Essington,” she said.
“It is now rare to find a native gecko on Darwin houses, and the nocturnal lizards whose appearance and vocalisations are so familiar to local householders are actually ‘Asian House Geckos’.
“Native geckos are still abundant in bushland surrounding Darwin, whilst the Asian invaders are relatively uncommon in natural habitats.”
Ms Scrymgour said one of the main concerns with finding the Mourning Gecko in Darwin is that most of its populations are unisexual.
“They have an unusual reproductive strategy which allows populations to consist only of females, as males are not necessary to fertilise and initiate egg production, and permits the Mourning Gecko to be a very successful invasive species.” she said.
Meanwhile, another lizard virgin birth is soon expected in England. Flora, a Komodo dragon at Chester Zoo in England, has laid fertile eggs despite never having had a mate. DNA tests confirmed Flora was the sole parent, says Chester Zoo curator of lower vertebrates Kevin Buley.
"Essentially what we have here is an immaculate conception,” he said, adding that the eggs could hatch as soon as Christmas. "We will be on the look-out for shepherds, wise men, and an unusually bright star in the sky over Chester Zoo," he joked, according to an online report from National Geographic.
The Associated Press reports that 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. Sole sex reproduction is hardly ever seen in such complex animals, having been documented in just 0.1 percent of vertebrates, a study team documents in the current issue of the journal 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.
The study team added in the article that though it’s not uncommon for female dragons to lay eggs without mating, such eggs are not usually fertilized. “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
http://www.westender.com.au/stories.php?s_id=395
“Historically, Darwin’s common house gecko was a native species but this has been mostly displaced by the Asian House Gecko which is thought to have been introduced during the early days of European settlement at Port Essington,” she said.
“It is now rare to find a native gecko on Darwin houses, and the nocturnal lizards whose appearance and vocalisations are so familiar to local householders are actually ‘Asian House Geckos’.
“Native geckos are still abundant in bushland surrounding Darwin, whilst the Asian invaders are relatively uncommon in natural habitats.”
Ms Scrymgour said one of the main concerns with finding the Mourning Gecko in Darwin is that most of its populations are unisexual.
“They have an unusual reproductive strategy which allows populations to consist only of females, as males are not necessary to fertilise and initiate egg production, and permits the Mourning Gecko to be a very successful invasive species.” she said.
Meanwhile, another lizard virgin birth is soon expected in England. Flora, a Komodo dragon at Chester Zoo in England, has laid fertile eggs despite never having had a mate. DNA tests confirmed Flora was the sole parent, says Chester Zoo curator of lower vertebrates Kevin Buley.
"Essentially what we have here is an immaculate conception,” he said, adding that the eggs could hatch as soon as Christmas. "We will be on the look-out for shepherds, wise men, and an unusually bright star in the sky over Chester Zoo," he joked, according to an online report from National Geographic.
The Associated Press reports that 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. Sole sex reproduction is hardly ever seen in such complex animals, having been documented in just 0.1 percent of vertebrates, a study team documents in the current issue of the journal 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.
The study team added in the article that though it’s not uncommon for female dragons to lay eggs without mating, such eggs are not usually fertilized. “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
http://www.westender.com.au/stories.php?s_id=395