OLL LEWIS: Back from the dead

Apart from the fact that his puns are terrible and he has an obsession with the more surreal side of Internet culture, Oll Lewis hasn't put a foot wrong since we started this bloggo-thing. Because of his interest in things aquatic he has been co-ordinating the lake and sea monster news for the CFZ for some years now, and as regular readers of this bloggo will already know he is letting this obsession spill over online. However, he also has an obsession with Wales - no, not the big, spouting, there-she-blows type, but the principality..

Every so often the media will write a story about the latest efforts to clone an extinct animal. Usually this is just an excuse for the journalist to try to kid their readers and themselves that, thanks to modern technology, extinction need not mean that a species is gone forever or that their childhood fantasies of seeing dinosaurs in the flesh will soon be realised. This is sadly things are never that simple. There is the technological potential to bring back a range of recently extinct species, but there are certain problems inherent in this.

The most obvious problem concerns why a species may have become extinct in the first place. For example if habitat destruction or climate change was a major contributor to the extinction of a species are there still suitable areas where the species can be reintroduced to the wild, where it will not threaten the survival of other species?

The second problem is that of genetic diversity. In order to bring a species back from the dead in such a way that it would not simply end up as a solitary freak show style exhibit in one of the worlds less reputable zoos scientists would need a large number of DNA samples from separate, preferably unrelated individuals. If the clones all share the same genes or similar then this would give the species as a whole very little resistance to disease and an increased susceptibility to genetic disorders. When a gene-pool becomes limited in this way it is known as a genetic bottle neck and it is a contributing factor to almost all extinctions not caused by cataclysmic events. In nature this occurs when groups become fragmented and genetically isolated from one another causing inbreeding. Eventually over successive generations, genes tend to become homozygous amongst the group as a whole further reducing the gene-pool. Typically if a species were extinct, by the time efforts are made to clone them there will only be a small number of genetically viable samples and even these samples will have come from a severely reduced gene-pool.

It is the problem of genetic diversity that most effects two of the highest profile projects to resurrect extinct species; that of the thylacine and the woolly mammoth. Due to the degradation of the DNA over time in both species it is a huge challenge to even obtain one complete sample, let alone the numbers needed if one were to ever see these creatures being reintroduced into the wild.

In some cases it may indeed be possible to bring a recently extinct species back to the wild, if those two main problems can be tackled, and indeed if the vast amounts of funding that would be needed for such an endeavour could be found. However, this also presents an ethical problem too: is it better to send vast amounts of money resurrecting one species that will doubtless have to be mollycoddled to such an extent that they could only just be described as wild, or is it better to spend that money protecting hundreds of other species from extinction in the first place? Personally I’d rather have the money spent on efforts to prevent extinction, but I’m sure other people’s opinions will differ from my own.