The purple crowned fairy wren holds the key to immune function

A study by Monash scientists found that the iconic purple-crowned fairy wren could hold the key to a better understanding of immune function.

The long-term study, which took place at Mornington Wildlife Sanctuary, run by collaborator Australian Wildlife Conservancy (AWC), was published today in Proceedings of the Royal Society B.

“Maintaining constitutive immune function (immune surveillance) is important for people to be prepared for new infections, but it is potentially costly for the individual,” said study lead author Dr. Michael Roast, of the Monash University School of Biological Sciences.

“These costs cannot be measured using experimental methods that introduce immune challenges,” he said.

“But in a wild bird population we were able to measure individual levels of immune function and assess how this relates to fitness by monitoring subsequent individual survival, acquisition of dominant breeding positions and reproductive success.”

It turns out that constitutive immune function doesn’t cost the individual much.

“We observed that several immune investment strategies correlated with high survival, which could reflect a dynamic disease environment,” said Dr Roast.

Purple-crowned wrens (Malurus coronatus coronatus) are endangered Australian endemic birds that live in family groups year-round occupying the same territory along rivers and creeks of the tropical savannah.

The scientists focused on a basic study population of birds at Mornington Wildlife Sanctuary, which had been banded in color since 2005.

In this habitat, purple-crowned wrens are exposed to a variety of parasites with recorded infections.

Researchers measured constitutive levels of immune function among individuals in the wild purple-crowned fairy wren population over five years and evaluated how these measures of immune function correlated with fitness outcomes by monitoring subsequent individual survival. , the acquisition of dominant breeding positions and reproduction. success.

“We found no evidence of a trade-off between constitutive immune function and reproduction, which might be expected if individuals with limited resources are forced to invest in immune function or reproduction,” said Dr. Roast.

“Instead, the differences between individuals might be more important if high-quality individuals are able to acquire breeding positions and can invest in both reproduction and immune function.”