SCIENCE LAB SCARES : KAKAPO CULTURE

ACCORDING TO SCIENCE : '' It's the parasites and pathogens that really did make us as to who we are.''

YES - it's a parasite, but a parrot under severe stress may just need it. For decades, the kakapo has been climbing its way back from the brink of extinction.

Luckily, the green parrot, found only in New Zealand, is a good climber. [It has to be, since it cannot fly.] And the bird has had plenty of help from humans who are managing its tiny, but growing population.

But conservation is a complicated work. And according to a study published in the journal Current Biology, the birds' centuries-long decline has been accompanied by another, less visible change. Parasites that once depended on the bird have diminished more than scientists would have expected.

That might not seem like such a tragedy, given how most humans feel about parasites. But their role can be more complicated :

In some cases, the relationship between host and parasite is mutually beneficial. And when extinction is a possibility for both parrot and parasite, that relationship warrants more investigation.

'' When you're dealing with extinction and biodiversity loss - of anything - there are impacts we still don't understand,'' said Alexander Boast, an author of the new study and a paleoecologist in the Bioeconomy Science Institute in New Zealand.

Marlene Zuk, an evolutionary biologist at the University of Minnesota who was not involved in the study, said that parasites and hosts can build deep, complex relationships over many years, a notion that has become increasingly clear to conservationists.

'' It's not that parasites and pathogens are always good for us,'' she said. 

'' It's that they really did make us who we are.''

There is evidence, for example, that parasites -including those that cause some harm to their hosts, like intestinal worms - may help animals, and even humans, develop their immune systems.

So, for instance, the research raises questions about whether conservationists need to rethink their approaches to certain veterinary practices used to keep the still-endangered birds healthy, like deworming.

The World Students Society thanks Jacey Fortin.