Fairy wrens: Accountants of the animal kingdom

Mar 18, 2011
Image credit: Australian Wildlife.

A puzzling example of altruism in nature has been debunked with researchers showing that purple-crowned fairy wrens are in reality cunningly planning for their own future when they assist in raising other birds' young by balancing the amount of assistance they give with the benefits they expect to receive in the future.

Dr Anne Peters, of the Monash University School of Biological Sciences, together with co-authors Sjouke Kingma from the Max Planck Institute for and Michelle L. Hall of the Australian National University, have conducted a long term study of the cooperative breeding behaviour of fairy-wrens in tropical Australia.

The results, published in the prestigious journal The , show that helpers are not motivated by kindness.

"The study showed that the seemingly selfless little helpers are in fact carefully calculating accountants" said Dr Peters, senior author of the study.

Cooperative breeding, where birds apparently selflessly raise others' offspring, has long perplexed biologists as this behaviour runs counter to Darwin's theory of natural selection, which predicts that individuals invest only in their own reproduction.

Fairy-wrens are habitual cooperative breeders. The helpers are generally older silblings or half-siblings of the current nestlings, and their behaviour is likely explained by an instinctive desire to see more of their shared genes entering the .

Purple-crowned fairy-wrens extend this assistance to unrelated nestlings.

Dr Peters' study shows that these apparently altruistic helpers are actually playing a selfish game: they help when their chances of inheriting the current breeding territory are greater, and they are thus helping to raise their own future assistants.

"Ours is the first study to show that helpers at the nest adjust their behaviour precisely according to multiple potential rewards: they provide food to kin, and to unrelated nestlings to produce future helpers of their own," Dr Peters said.

"However, we suspect once more researchers look at their study species in this dual light, more cases will be found of helpers that can do their sums so precisely."

Explore further: Feline fame in cyberspace gives species a boost

Related Stories

Mother's little helpers

Aug 16, 2007

An Australian bird has been found to produce smaller, less nourishing eggs when it breeds in the presence of other ‘helper’ birds that provide child-care assistance. This unique adaptation enables the ...

Faithful males do not bring flowers

May 19, 2009

(PhysOrg.com) -- Fairy-wrens are notorious for their infidelity: despite living in seemingly harmonious monogamous pairs, females produce mostly illegitimate young, and males spend more time courting other ...

A helping hand from the grandparents

Dec 21, 2007

A team of scientists led by the University of East Anglia has discovered the existence of ‘grandparent’ helpers in the Seychelles warbler – the first time this behaviour, which rarely occurs except in humans, has been ...

Study reveals why starling females cheat

Jun 20, 2007

While women may cheat on men for personal reasons, superb starling females appear to stray from their mates for the sake of their chicks, according to recent Cornell research published in the Proceedings of the Royal Society of ...

Recommended for you

The ants that conquered the world

20 hours ago

About one tenth of the world's ants are close relatives; they all belong to just one genus out of 323, called Pheidole. "If you go into any tropical forest and take a stroll, you will step on one of these ...

Ants show left bias when exploring new spaces

Dec 23, 2014

Unlike Derek Zoolander, ants don't have any difficulty turning left. New research from the University of Bristol, UK published today in Biology Letters, has found that the majority of rock ants instinctively go lef ...

User comments : 4

Adjust slider to filter visible comments by rank

Display comments: newest first

antialias
4.5 / 5 (2) Mar 18, 2011
What i've been saying all along: Altruism is a form of egotism. this doesn't mean that it's bad (quite the contrary) but that it's not some life-defying, beatific personality trait. It's just a roundabout way of being beneficial to the individual by creating a stable environment/society in which the individual can expect that others will help it when the need arises (and where the amount of hard competitors decreases)

Revel in your altruism!
iKnighty
not rated yet Mar 19, 2011
I can't agree with the study. How did they show those birds are actively planning for their future?
I would speculate they are just instinctively altruistic, the same way we are, because altruism begets more altruism and thus altruism begets better survival potentiality. And thus the trait of altruism lives on.
alanborky
not rated yet Mar 19, 2011
Human altruists're invariably poorly rewarded for their efforts, to the point of often being physically abused if they dare pay attention to anyone else's problems, (see any hospital A&E department on a Saturday night).

To prove this theory they'd need to demonstrate one or more continuous lineages over many generations received their 'just rewards'.

They'd also need to keep the 'linking' generations in such lineages in isolation not only from the general community but each other to preclude the possibility it's a tendency acquired by demonstration/observation.
dan42day
1 / 5 (1) Mar 21, 2011
I can't agree with the study. How did they show those birds are actively planning for their future?


They found spreadsheets on their IPads.

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.