Invasive species and climate change: does immunology have a role?

Climate change may alter the frequency and pattern of transmission of disease organisms in many ecosystems._ The survival of wildlife species in response to altered threats of infection will reflect their species-specific immune systems._ Species adapted to respond to a broad spectrum of immune challenges _- often invasive species _- may adapt to climate change more successfully._ An interesting model species for exploring how immune responses are shaped by ecological factors is the brown-headed cowbird, a highly successful invasive species. The New World cowbirds (Molothrus spp) are obligate brood parasites, and the brown-headed cowbird is an extreme-generalist that lays its eggs in the nests of many other species. Brown-headed cowbirds are exposed to diverse parasites and microbes associated with their many foster parent species and habitats, and this exerts evolutionary selection on their immune system._ We have found a suite of cowbird immune defenses that are more effective than the defenses of related species that are not parasitic and not invasive._ This eco-immunological approach to the vertebrate immune system provides insight into how invasive species will fare in an era of climate change.

Contact

  Jason Hill
  ecologyservice@psu.edu