The Means of Mutation

Chernobyl forest winter time. On courtesy of bbc.co.uk
Is the exclusion zone a radioactive death trap or a haven for wildlife?
Performing a simple internet search on Chernobyl wildlife, you will undoubtedly find many article praising the Zone for its richness of species, but taking a closer look at it all, it is not at all what it seems. 

The popular idea of that the Chernobyl area has turned into a large natural zoo of eastern Europe may derive from repeated sightings of wolves, boars and wild Prewalski's horses because it is indeed true that these creatures roam freely in the zone but if spending just a brief thought on it all, it only means one thing; that wild animals tend to seek places uninhabited by humans. It doesn't mean that they're not affected by radiation. 

After the Chernobyl disaster, different kinds of research have been performed, in order to determined exactly how the fallout has affected flora and fauna but even to this day, 28 years later, it is not fully known how. As I have written in previous posts, we don't even know enough about how concentrated amounts of radiation affect living organisms to be able to understand the full extent. 

A relatively common belief is that the shorter the life span of a species, the faster it adapts to changed environment but if so would indeed be the case, all the insects, rodents and smaller birds of Chernobyl would be fully adapted by now, but obviously they are not. We find an example in a study made by made by a team of researchers from Norway, France and the US (led by Professor Timothy Mousseau from the University of South Carolina, US, and Dr Anders Möller from the University of Paris-Sud, France.), concerning small birds of Chernobyl. The study was performed on 550 individuals from 48 different species of birds and the result showed that the average size of the brains of those birds was about 5% smaller than those of birds not residing in the exclusion zone. The conclusion was that this was a direct effect of radiation, and this divergence was especially significant concerning younger individuals. Stressed birds have the ability to change the size of some of their organs in order to become less sensitive to difficult environmental conditions and especially migrating birds that travel long distances often shrink certain organs as they use up energy. The brain is however the last organ to be sacrificed, according to Möller and Mosseau, which pretty much leaves increased background radiation as the only plausible reason. 

However, the research of Anders Möller and Timothy Mosseau doesn't stand uncontradicted. The Ukrainian biologist Sergey Gaschak who was a former colleague of Möller and Mosseau, implies that their research is all wrong. "You can measure an animal 10 times and 10 times you can get a different result" Gaschak said in an interview for the magazine "Wired" in 2011. Further on, Gaschak claimed that his data was distorted and misinterpreted by Möller and Mosseau, but there was no description of how, other than that Möller stated that Gaschak didn't want his name published on the paper. We face something implying a personal drama between the researchers, so I'll leave the part of Sergey Gaschak with the words that his dream concerning the Zone turning into a permanent healthy wildlife reserve may, due to radiation, be quite impossible in the near future. I will get back to Gaschack once I've investigated him further. 

Let's get personal for a brief moment. During my stay in the zone, I noticed that the mosquitos seemed to be significantly larger than average mosquitos, but also that their bites barely itched at all. Mind you, these are subjective observations so I cannot grant the accuracy of this, but still - may it be that radiation has affected the substances of the female mosquitoes' saliva that normally cause an itch? Personally, I cannot tell whether it's like that or not, but one thing I know for sure is that getting bitten by a Chernobyl mosquito won't hurt you more than getting bitten by a "normal" mosquito. The exposure to radiation has hurt the species rather than turning them into mutated threats to other species. So no - Spiderman could not happen in real life. 

Other studies, performed by Timothy Mosseau has shown that the forests around Chernobyl aren't decaying the way they should. We're talking about the same forests that suffered heavy fallout; that were cut down, but still grew back, heavily radiated. The reason why the process of decay has become inefficient is, according to Mosseau, that even the decomposers, insects, microbes and fungi, are affected by the increased levels of  radiation.

The Red Forest is now composed largely by dead trees, but they are not decaying:  
“Apart from a few ants, the dead tree trunks were largely unscathed when we first encountered them. It was striking, given that in the forests where I live, a fallen tree is mostly sawdust after a decade of lying on the ground.” 
Timothy Mosseau with his samples. From this article. 
says Timothy Mosseau in an interview with the Smithsonian. You may read the full article here.
Mosseau takes up a direct problem regarding the Zone, as well as he takes us back to an old question: Exactly how has the high levels of radiation affected the flora of Chernobyl, in other matters than killing and deforming them? Cases of gigantism of trees, mushrooms and berries have been reported, but how does that correspond to the truth? We do know that flora reacts differently to radiation than fauna. We know that for example soybean plants in the zone do not only produce fertile seeds, but has evolved to protect themselves against radiation and by now we also know that  at least some kinds of fungi are highly capable of feeding on radiation. Plants and fungi may have an innate defense or ability to cope with radiation, but of that we still know too little about these things to get to proper overall conclusion. Effects are probably varying from species to species concerning flora, and only further research will make us wiser.

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