Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Deception fuels domestic bliss

21.11.2001


Happy families: heartwarming domestic scene or symphony of self interest?
© Photodisc


Evolution may make men ignorant and gullible.

Gentlemen: ignorance is bliss and gullibility is the best policy. A new mathematical analysis suggests that evolution favours babies who don’t much resemble their fathers, and males who believe their partner when she says a child looks just like him.

Anonymous-looking newborns make for uncertain fathers. But they also allow men to father children through undetected adultery, Paola Bressan of the University of Padova calculates1. The assertion - common across many cultures - that babies are the spit of their dad, is a way to get men to care for their offspring despite their uncertainty, she adds.



Mummy, daddy and baby might look like a heartwarming scene of family togetherness. But evolutionary biologists have no truck with such sentimental nonsense: to them, each of the trio is pursuing its own, often competing, interests.

The wild card is adultery. A baby comes into the world unsure of whether the male providing for it is its biological father. Being rumbled could mean neglect, or worse - infanticide. It’s easy to see how, in an evolutionary sense, babies might not want to resemble anyone in particular.

Whether fathers benefit from having recognizable babies is trickier. If dads pass on some genetic badge that allows them to identify their children, they could avoid raising another man’s child. But they will not be able to sneak any offspring into other families.

Bressan proposes that these two forces cancel each other out. Having anonymous babies stops fathers mistakenly rejecting their own children, which, in a slowly reproducing species such as humans, is probably a cost greater than that of raising someone else’s child. When the interests of babies and mothers are also taken into account, genes for anonymous babies should spread.

Human babies certainly seem to be masters of disguise. Neutral observers asked to match infants to their fathers do only slightly better than chance.

In fact, some of newborns’ features seem designed to enhance anonymity, says evolutionary biologist Mark Pagel, of the University of Reading. He points to the blue eyes and blond hair of many newborn Europeans, which result from genes being switched off at birth.

Could evolution mark babies with their father’s identity? Pagel thinks so: "There’s a lot of genetic variation to play with, and all sorts of things that are very easy to produce developmentally," he says.

Mother’s instinct

So everybody’s happy? Not quite: if all babies are anonymous and fathers are uncertain, males would invest less in kids whether they sired them or not.

A mother’s strategy to counteract this, says Bressan, could be to remark on the baby’s likeness to his father. Her mathematical model shows it can benefit a father to believe these assertions and increase his care for the child, as long as the chance that he is being deceived is slim enough.

Denson McLain, a behavioural ecologist at Georgia Southern University likes this idea. "The harm to a father of being sceptical towards is own children is greater than the cost of rearing someone else’s child," he says.

McLain has found that mothers remark more on their baby’s resemblance to their partner if he or his relatives are there to hear her than if he is absent.

Pagel, however, doubts that evolution would favour trusting males. The warm glow that dads get from hearing that junior has their nose might simply be "good old-fashioned vanity", he suggests.

References

  1. Bressan, P. Why babies look like their daddies: paternity uncertainty and the evolution of self-deception in evaluating family resemblance. Acta Ethologica, in the press (2001).

JOHN WHITFIELD | © Nature News Service
Further information:
http://www.nature.com/nsu/011122/011122-9.html

More articles from Life Sciences:

nachricht Fish recognize their prey by electric colors
13.11.2018 | Rheinische Friedrich-Wilhelms-Universität Bonn

nachricht The dawn of a new era for genebanks - molecular characterisation of an entire genebank collection
13.11.2018 | Leibniz-Institut für Pflanzengenetik und Kulturpflanzenforschung

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: A Chip with Blood Vessels

Biochips have been developed at TU Wien (Vienna), on which tissue can be produced and examined. This allows supplying the tissue with different substances in a very controlled way.

Cultivating human cells in the Petri dish is not a big challenge today. Producing artificial tissue, however, permeated by fine blood vessels, is a much more...

Im Focus: A Leap Into Quantum Technology

Faster and secure data communication: This is the goal of a new joint project involving physicists from the University of Würzburg. The German Federal Ministry of Education and Research funds the project with 14.8 million euro.

In our digital world data security and secure communication are becoming more and more important. Quantum communication is a promising approach to achieve...

Im Focus: Research icebreaker Polarstern begins the Antarctic season

What does it look like below the ice shelf of the calved massive iceberg A68?

On Saturday, 10 November 2018, the research icebreaker Polarstern will leave its homeport of Bremerhaven, bound for Cape Town, South Africa.

Im Focus: Penn engineers develop ultrathin, ultralight 'nanocardboard'

When choosing materials to make something, trade-offs need to be made between a host of properties, such as thickness, stiffness and weight. Depending on the application in question, finding just the right balance is the difference between success and failure

Now, a team of Penn Engineers has demonstrated a new material they call "nanocardboard," an ultrathin equivalent of corrugated paper cardboard. A square...

Im Focus: Coping with errors in the quantum age

Physicists at ETH Zurich demonstrate how errors that occur during the manipulation of quantum system can be monitored and corrected on the fly

The field of quantum computation has seen tremendous progress in recent years. Bit by bit, quantum devices start to challenge conventional computers, at least...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

“3rd Conference on Laser Polishing – LaP 2018” Attracts International Experts and Users

09.11.2018 | Event News

On the brain’s ability to find the right direction

06.11.2018 | Event News

European Space Talks: Weltraumschrott – eine Gefahr für die Gesellschaft?

23.10.2018 | Event News

 
Latest News

The dawn of a new era for genebanks - molecular characterisation of an entire genebank collection

13.11.2018 | Life Sciences

Fish recognize their prey by electric colors

13.11.2018 | Life Sciences

Ultrasound Connects

13.11.2018 | Awards Funding

VideoLinks
Science & Research
Overview of more VideoLinks >>>