Zoo celebrates virgin Komodo birth

donderdag 25 januari 2007 09:32 | louise | 2282 keer bekeken | 0 reacties | 0 x aanbevolen

Chester Zoo is celebrating the 'virgin birth' of five Komodo dragons after the hatching of a clutch of eggs laid by a female who has never mated with a male.



Paternity tests have proved that five young born to a female called Flora were conceived by parthenogenesis, a form of asexual reproduction that is known to take place in lizards, but has only recently been documented in this species.

Flora laid her clutch of seven viable "immaculately conceived" eggs in May, despite never mixing with or being mated with a male.

The young, born between January 15 and 22, are all male, weigh up to 40oz and measure 18 inches long. Two more eggs remain in incubation and are expected to hatch soon.

Kevin Buley, Curator of Lower Vertebrates and Invertebrates at Chester Zoo, said: "Flora is oblivious to the excitement she has caused, but we are delighted to say she is now a mum and dad. When the first of the babies hatched, we didn't know whether to make her a cup of tea or pass her the cigars.

"Even though they are only a few days old, our baby dragons are doing very well and receiving the expert care they need at this time."

The young lizards are currently being kept in the zoo's off-show area, where they are fed a diet of crickets and locusts. They will be moved to a public enclosure around Easter time and are expected to grow to a massive three metres long.

Komodo dragons, the world's largest lizard, are a threatened species with only about 4,000 thought to live on three Indonesian islands.

Flora, who is part of a European breeding programme, was confirmed as a virgin mother-to-be last year when genetic fingerprinting on three of her eggs that collapsed showed she was both the mother and the father. The eggs are not clones, but all their DNA comes from Flora.

Parthenogenesis, which is derived from the Greek words for virgin birth, occurs when an egg spontaneously begins dividing as if it were an embryo, without being fertilised by sperm. It is known to have produced live young in about 70 vertebrate species, mostly reptiles and fish, and is thought to be encouraged when females are separated from males.

All Komodo dragons, Varanus komodoensis, bred in this way will be male and as such could have important implications for their conservation.

Most zoos keep only female lizards, with males moving from zoo to zoo for breeding purposes. This practice may need to be changed because it may promote parthenogenesis, which in turn reduces the genetic diversity of the species.

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Bron: Timesonline