Monday, November 15, 2010

Week 4 : Let's impress people with Siberian Foxes


The Silver Fox experiment

This story started in 1959 in the Institute of Cytology and Genetics of the (former-)U.S.S.R. Academy of Science in Novosibirsk, Siberia. A Russian scientist called Dmitry K. Belyaev, director of this institute, intended to carry out experiments on animal domestication process. The most famous case of domestication is the case of Canis lupus (wolf) becoming Canis familiaris (dog).
In order to chose a proper subject for his experimentations he wanted an animal that could be genetically close to the dog and the wolf and at the same time that still hasn’t been domesticated, just like foxes. As Siberia was abundant in silver foxes bred for their fur, it was the opportunity for Belyaev to work on his project with these foxes.
Dmitry Belyaev with some of his domesticated silver foxes, in 1984.


His experimental process was quite simple to understand and to set up. In every litter he would select the fox cubs that showed no aggressiveness and the less fear towards homo sapiens as possible. The results came quite quickly, that is to say that in a remarkably small number of generations (10 to 15 generations) some physical characteristics appeared to differ from usual foxes.


Only by selecting foxes on behaviour it changed their physical aspect. Those changes led to the fact that foxes look more “cute”. Indeed they had juvenile characteristics : floppy ears, large skull for their length, curved tail. Also they had lack of pigmentation as their new ecological niche (cages) didn’t require to stay hidden. In other words they looked more like
dogs.
          White areas on the fur                                curved tail                                         floppy ears


            Keeping juvenile traits as adult is called neoteny. This is a natural process that makes babies look cute so that their parent have a greater tendency to take care of them. Very easy to demonstrate that the more it looks cute the more we want to take care of it.

Let’s make a simple test : if you were a parent and you had two kids (supposedly the pair of pictures below) and you had to decide to take care the most about one of them. To which one do you thing you would pay more attention?


As a conclusion this experiment showed that selecting individuals by behavioural traits ( here tameness, friendliness with humans) triggered physical changes. Those changes are to be compared with wolves and dogs. Wolves have been keeping mainly the same aspect and behaviour for a long time (like foxes that were not selected). Dogs show much more difference with wolves in a juvenile way (like selected foxes in few generations). This can explain how today there is plenty of dog breeds, with different physical characteristics.


Dmitry Belyaev died in 1985 and the experiment are from that year under the direction of Lyudmila N. Trut (picture below). It is now 50 years that these experiments last for the good of genetic and metabolic researches. After all, even if they are still helpful to science progress and cause no physical pain on foxes they still involve animals in cage. Some are even sold as pets.
Once a wise man1 said "the day we'll realize animals have a thought without language we'll die of shame for locking them up in zoos" This is the dilemma it is all about.


Bibliography :

 Lyudmila N. Trut, Early Canid Domestication: The Farm-Fox Experiment, American Scientist, volume 87

1The wise man is Boris Cyrulnik an etholog, quoted from La fabuleuse aventure des hommes et des animaux with Karine Lou Matignon, Frédéric Fougea.

Webography :

http://en.wikipedia.org/wiki/Domesticated_silver_fox
http://en.wikipedia.org/wiki/Neoteny

2 comments:

  1. Fascinating research and hilarious intrusion of Mister Lagerfeld into the world of fox puppies. He is quite foxy himself, indeed. I just hope he won't ever look at the blog. You people have no respect for fashion divas; shame on you. I had a good laugh though...
    Excellent work, as usual, both in terms of language use and content interest. For your next blog, spend a bit more time on personal commentaries. I wish you had developed this dilemma you are refering to at the end of the entry. Being a scientist involves, not always but still oftentimes, experimentation on living beings; that's certainly one of the problematic aspects of science--animal and human experimentation is still taking place today; they might one day be replaced by computer models, but at the same time, will a computer be able to foresee the effetcs of a specific product/experiment on a living body whose complexity will probably never be matched by a computer. The future will tell...

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  2. Thank you, we always try to find topics that refer to major issues but that are at the same time quite unknown. This is our challenge, the aim is to permit to interest whoever during a diner with complex things in simple words. That's our personnal "touch". We really transform the informations we get and we invest a lot of time (which isn't a problem because we always choose subjects that firstly interested us)to make an attractive and unusual text out of it. The sixth week's topic is really a personnal work in term of point of view but it brings at the same time some keys to look brilliant during a diner party.
    As for the fact the quote leads to many questions related to animal experimentation and even bioethics we sure concluded this way as scientists. We couldn't not finish with saying "So that's an 50 year old experiment in Siberia that hundreds of foxes still have to undergo, amazing huh?"
    We already had to deal with these dilemmas many times in English class during our Bachelor. That's still one of the major problem of Science progresses that are remarkable but still need living beings, as you said we cannot completely match a living metabolism with a model. The complexity of it is such that according to me it will take centuries at least to come to understand the main aspects of life and its miscellaneous forms and processes. An endless question : Should we still experiment on living creatures as they bring us the keys to save human lives of even themselves?
    My opinion follow's (with no pretention of comparison) Blaise Pascal's who said something like "Science should stay at the theory level and never become technical" or in other words that there should not be applications of scientific research because a Science is defined as something that is "true" untill is demonstrated to be false. I believe that it is possible that one day all our "sciences" can change their fundamental laws and that all their applications would have to be changed because their consequences would be considered as "wrong". Animal testings being an "application" I also believe they should not be.
    However I can't allow myself to feel entirely against it because I know so well that for now it permitted to save many lives through pharmaceutical researches, medical researches, biological researches and so on.
    And as a future scientist I hardly imagine making discoveries allowing great applications without creating a technique that goes with it. It would be also hypocritical to use technologies (cellphones, computers, TVs and so on) and say we should keep on thinking about theories and never apply them.
    In a nutshell, I don't agree with animal testing but I can't as a scientist reprehend it totally.

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