In analyzing malaria mosquitoes in sub-Saharan Africa, a Cornell-led team of researchers finds evidence of two very different evolutionary paths in the immune systems of neighboring mosquito groups.

Genes in animal immune systems may evolve in one of two main ways in the constant fight against pathogens: They may evolve diverse forms of genes (alleles) to fight a wide variety of pathogens, or when only a few pathogens dominate, they may evolve one or a few alleles that specialize against common infections. The Cornell researchers have found evidence of both these adaptive strategies occurring in the same immune-defense genes in different subpopulations of the human malaria vector mosquito, Anopheles gambiae.

via PhysOrg.com.