What's love got to do with it? Finches could have the answer

Zebra finches which chose to be together were more successful at breeding (iStock)
Zebra finches which chose to be together were more successful at breeding (iStock)

Celine Dion sang about it and now researchers have documented the power of love in zebra finches and it is surprisingly similar to humans.

For men and women, finding love in the modern age is increasingly about online dating, apps including Tinder and reality TV shows like The Bachelor.

It can be a minefield with nervous flirting, awkward first dates and rejection, all in the name of finding "the one".

The energy and time spent on finding a perfect partner isn't necessarily the most efficient evolutionary behaviour for reproduction, and German ornithologists have studied some birds to do a cost/benefit analysis of it.

Instead of using the internet to find love, zebra finches use Twitter of a different kind to find a mate.

In a study published in PLOS Biology today, Malika Ihle, Bart Kempenaers, and Wolfgang Forstmeier from the Max Planck Institute for Ornithology described their speed-dating experiment with the bird most commonly found across central Australia.

They already share a number similar traits to humans, including mating monogamously for life and sharing parental care.

Female finches choose a mate which is specific to their preferences and there is no unanimity on which is the cutest male.

The researchers used a population of 160 and set up a speed-date with 20 females to freely choose between 20 males. Once paired off, half were allowed to stay together, while the others were rearranged "forcibly pairing them with other broken-hearted individuals".

The couples were then left to breed, where the researchers counted the number of live offspring as well as the number and paternity of dead embryos and chicks.

Surviving chicks from chosen pairs was 37 percent higher than couples forced together. The nests of non-chosen pairs had three times as many unfertilised eggs and markedly more chicks died after hatching.

Most of the deaths happened within the first 48-hours after hatching, which is a critical time for parenting duties – non-chosen fathers were much less diligent in doing their bit.

But it wasn't only the mating which showed stark differences – courtship differed a lot too.

"Although non-chosen males paid the same amount of attention to their mates as the chosen ones did, the non-chosen females were far less receptive to their advances, and tended to copulate less often," the researchers say.

The non-chosen couples were significantly less "lovey dovey" than their loved-up counterparts and there was also a higher level of infidelity.

The frequency of the males looking for a new partner increased as time went on, but the females roamed less.

The study's authors believe the birds choose their mate because they find them stimulating in a way which isn't obvious to outsiders.

This "turns on" the female finches, which encourages successful breeding and commitment to offspring.

The authors say their study is consistent with some studies relating to love-based versus arranged marriages.

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