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Monsters and Moas

The idea of bringing dinosaurs back to life as shown in the blockbuster movie Jurassic Park is pretty far-fetched, according to a Victoria University student who is doing research into the DNA of extinct species.

Alan Cooper, who is completing a PhD at Victoria and currently doing research at the Smithsonian Institution in Washington DC, says the movie deals quite well with some aspects of the DNA technology involved "but it hops over the problem areas."

The main problems are the virtual impossibility that a complete strand of DNA from a dinosaur could have survived the past 70 million years, and even if it had, the huge difficulties of producing a living cell with it.

"I'd hate to say it won't ever be done, because science does make extraordinary progress, but in the foreseeable future I just can't see how it would be possible," he says.

Cooper's research, in Dr Geoff Chambers's laboratory in the School of Biological Sciences, has mainly involved birds, including extinct species such as the moa. He has also become involved in a project to obtain the DNA of the the dinosaur Tyrannosaurus rex.

"An eminent American paleontologist who is working on dinosaurs and was involved in the Jurassic Park movie has found a bone of Tyrannosaurus rex which has been fossilised and completely sealed round the outside, but seems to have cell material preserved inside. If that's correct it's pretty amazing. A friend at Berkeley who knew I was working on ancient DNA asked me to help examine the bone to see if we can obtain dinosaur DNA. Personally I'm not too optimistic -- in fact I would say it's pretty unlikely after 70 million years.

"But even if we succeed, the idea that we could reproduce a T. rex from it is ridiculous. All we're going to achieve is possibly find out whether the dinosaur was more related to birds or to crocodiles."

Cooper says that in the bones of extinct species, it is only possible to find a lot of small damaged fragments of DNA, not complete sequences.

"There are huge numbers of genes involved, and you'd be lucky to find half or even a quarter of them. Even if you had the lot you couldn't put them all together into chromosomes, and you need all the chromosomes."

There are other problems with the scenario as presented in Jurassic park, even ignoring the fact that no amber-trapped mosquitoes yet found are old enough to have sucked the blood of Jurassic dinosaurs.

Eagle-eyed scientists have noted that one mosquito shown in the film has feathery antenna -- a sure sign that it's a male, and male mosquitoes don't suck blood. Another is of the genus Toxorhynchites whose living members aren't known to suck blood. And to add insult to injury, says Dr Eric Scott of Lincoln University's Department of Entomology and Animal Ecology, "...the abdomen in amber that is `drilled' for the blood is that of a male crane fly, or `daddy long legs', a non blood-sucking family of flies."

Alan Cooper is at present working in the United States "because that's where the money is" for his field of research. But he expects to return to New Zealand or keep strong links here.

"In terms of evolutionary study, New Zealand is one of the best study areas in the world," he says. "A very eminent evolutionary scientist said recently that New Zealand is as close as you can get to examining what the ecology of life on another planet might be like. The reason is that New Zealand had lots of dinosaurs and birds but no mammals, so we can study how the dinosaurs and birds evolved in the absence of the mammals, which are more efficient."

Cooper's research in New Zealand has involved studies of evolution in moas, kiwis and other large Australasian flightless birds.

"An interesting thing we've found through DNA study is that the evolutionary variation in moas is only about the same as in kiwis, even though moas existed long before kiwis. This suggests that some factor must have intervened to equalise the amount of variation. What we think happened is that New Zealand was submerged about 30 million years ago except for a few small islands, wiping out most of the moa and kiwi species that had evolved."

When the country emerged again above the ocean, just one species of each bird survived, and subsequent species of moas and kiwis evolved from them.