I've just been reading an article in the 2nd Oct 2010 edition of New Scientist titled 'Sparks fly over origin of altruism'.
There's some controversy over the works of three Harvard University scientists:
The Harvard 3 object to the standard equations for inclusive fitness because, they claim, amongst other things
Having read The Selfish Gene I think this is an important distinction. It's genes that are propagated using the individuals as their method of reproduction. While genes only exist within individuals it's the genes that are selected for depending on the reproductive success or otherwise of the individuals or group of individuals carrying them.
There is some correlation between the inclusive fitness of individuals and the inclusive fitness of genes but they're not the same thing and the Harvard 3 are simply saying that in the complex scenarios the inclusive fitness of individuals and the inclusive fitness of genes are different. What's more, they say this difference is important.
The article takes the ever popular case of the honey bee to demonstrate altruism. Quoting from New Scientist: "Altruism, in this context, refers to any behaviour which helps the chances of survival of others at the expense of the altruistic individual. Honeybees, which sting intruders to protect their hove and sign their own warrant in the process, are a classic example."
In this example one would typically say the individual honeybee it is being altruistic because it dies to saves the others. However, from the point of the genes in this individual the death of the individual is no big deal because lots of copies on the gene exist in all the other honeybees. That one copy be lost to protect all the other copies and the queen who generates these copies is an obvious win for the genes. In fact, each individual honey bee is so unimportant to the genes that the honey bees are not even fertile.
It's as wrong to think of the honey bee as an individual as it is to think of a human white blood cell attacking an intruder cell and dying in the process. Nobody would think of the blood cell as being altruistic. It's no more a separate genetic entity than the honey bee is. The honey bee example is not one of altruistic behaviour by the honey bee but instead is an example of selfish behaviour by the genes.
Later the New Scientist article states "Some biologists have embraced the new ideas [snip] They say theoretical biologists have always known that inclusive fitness was an approximation, though this seems not to have filtered through to experimental biologists, who have tended to take it as gospel." and later, regarding Grafen talking about needing to know lots of species specific information for genetic inclusive fitness "... it would only illuminate the process for one species. So it is better process for one species. So it is would be better to stick with inclusive fitness, rough and ready though it is, because it will enable bioligists to make predictions about how various species should behave - and indeed already has. Many of his peers agree, arguing that inclusive fitness should still be used as a "rule of thumb"."
If the rule of thumb can get it so wrong about the honey bee, which is held up as a classic example of that rule of thumb, what else can it be wrong about?
There's some controversy over the works of three Harvard University scientists:
- Martin Nowak
- Corina Tarnita
- Edward O. Wilson
The Harvard 3 object to the standard equations for inclusive fitness because, they claim, amongst other things
- only valid for interactions between pairs of animals - fine for solitary animals but not social animals like ants
- don't work for populations under strong evolutionary pressure
Having read The Selfish Gene I think this is an important distinction. It's genes that are propagated using the individuals as their method of reproduction. While genes only exist within individuals it's the genes that are selected for depending on the reproductive success or otherwise of the individuals or group of individuals carrying them.
There is some correlation between the inclusive fitness of individuals and the inclusive fitness of genes but they're not the same thing and the Harvard 3 are simply saying that in the complex scenarios the inclusive fitness of individuals and the inclusive fitness of genes are different. What's more, they say this difference is important.
The article takes the ever popular case of the honey bee to demonstrate altruism. Quoting from New Scientist: "Altruism, in this context, refers to any behaviour which helps the chances of survival of others at the expense of the altruistic individual. Honeybees, which sting intruders to protect their hove and sign their own warrant in the process, are a classic example."
In this example one would typically say the individual honeybee it is being altruistic because it dies to saves the others. However, from the point of the genes in this individual the death of the individual is no big deal because lots of copies on the gene exist in all the other honeybees. That one copy be lost to protect all the other copies and the queen who generates these copies is an obvious win for the genes. In fact, each individual honey bee is so unimportant to the genes that the honey bees are not even fertile.
It's as wrong to think of the honey bee as an individual as it is to think of a human white blood cell attacking an intruder cell and dying in the process. Nobody would think of the blood cell as being altruistic. It's no more a separate genetic entity than the honey bee is. The honey bee example is not one of altruistic behaviour by the honey bee but instead is an example of selfish behaviour by the genes.
Later the New Scientist article states "Some biologists have embraced the new ideas [snip] They say theoretical biologists have always known that inclusive fitness was an approximation, though this seems not to have filtered through to experimental biologists, who have tended to take it as gospel." and later, regarding Grafen talking about needing to know lots of species specific information for genetic inclusive fitness "... it would only illuminate the process for one species. So it is better process for one species. So it is would be better to stick with inclusive fitness, rough and ready though it is, because it will enable bioligists to make predictions about how various species should behave - and indeed already has. Many of his peers agree, arguing that inclusive fitness should still be used as a "rule of thumb"."
If the rule of thumb can get it so wrong about the honey bee, which is held up as a classic example of that rule of thumb, what else can it be wrong about?
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