Adaptive immunity and the evolution of long life across birds

How do some species live such a long time in a world with rapidly evolving pathogens and costly immune defences? It has been proposed that the evolution of adaptive immunity in vertebrates was key to their extended lifespans.

This form of immune defence creates long-lasting immunological memory and is highly targeted toward specific pathogens, reducing collateral damage to the host.

In contrast, the other arm of the vertebrate immune system, innate immunity, has lower developmental costs, lacks memory and is less specific causing increasing host damage over the course of life.I will test for the first time the prediction that adaptive immunity has been instrumental in the evolution of longer lifespans using comparative immunogenomics across birds.

I will launch four work packages (WP) to address whether: there have been greater gene family expansions in the adaptive versus innate immune system in longer-lived bird species (WP1); selection on the protein coding sequences of adaptive versus innate immune genes is stronger in longer-lived species (WP2 & WP3); and genomic adaptations in immunity have promoted the evolution of long life or were instead a consequence of extended lifespans (WP4).This project will help resolve the question of whether adaptive immunity advanced the evolution of long life and improve our fundamental understanding of how the vertebrate immune system evolves.