Friday 22 February 2013

sex + outbreeding = gamete altruism - kin selection

The above equation aptly summarizes George C. Williams' socio-biological conception of the cost of meiosis, after the genome-dilution conception had been rejected by John Maynard Smith.

Consider male gametes to be intra-specific parasite, then female gametes act altruistically in accepting fertilization. The paradox of sex is then the occurrence of this cellular altruism in many out-breeding sexual species, that is, in situations where kin selection cannot explain altruism.

John Maynard Smith's initial criticism that the cost of meiosis only arise in species with large eggs and small sperm (anisogamy) no longer applies to this socio-biological conception of the cost of meiosis, because fertilization between gametes of equal size (isogamy) would still be a case of co-operation among not related gametes. Why does not one of the gametes cheat instead and accept the resources but not the haploid genome of the gamete with which it fuses?

This is how Williams rebutted Maynard Smith's criticism. Unfortunately, the controversy did not continue but instead a potted story is being transmitted that was already obsolete at its inception, telling that Williams's cost of meiosis is the false and Maynard Smith's cost of males the correct concept of the cost of sex.

For example, see Lehtonen et al. (2012) or this Haiku associated to it at Hanna Kokko's web-site:
1.
Forget dilution.
Males are the cost of sex.
Wasting resources
2.
Males, a waste of time
Meiosis takes time too, but
it's not always bad
3.
World so full of sex
Genes not diluted at all
Males a waste of space 


P.S.: For quotes and references of the original arguments by Williams and Maynard Smith see here.