Newborn mice depend on mom's signature scent

October 04, 2012

For newborn mice to suckle for the very first time and survive, they depend on a signature blend of scents that is unique to their mothers. The findings, published online on October 4 in Current Biology, a Cell Press publication, reveal that mom's natural perfume consists of odors emitted from the amniotic fluid, which served to nourish and protect those young mice before they were born.

That's not what researchers led by Lisa Stowers of The Scripps Research Institute expected to find. Earlier studies in rabbits showed that suckling depends not on a complex odor brew but on a pheromone, a singular chemical factor that triggers a characteristic behavioral response.

"Surprisingly, unlike the rabbit, we found no evidence of a classic pheromone in the mice," Stowers says. "Instead, we found that the pup 'learns' the individual scent blend of the mom. Every mom is likely to have a different signature odor." It can't be isolated and purified in the way a pheromone can.

The discovery reveals that even innate behaviors like suckling aren't necessarily hard-wired. Nursing mouse pups must learn the smell of mom. The behavior is primed by the unavoidable experience of the amniotic fluid before birth and the secondary experience of that odor blend at the mother's nipple immediately after birth.

The fact that newborn rabbits initiate suckling in a different way has evolutionary implications. "These results suggest that mammalian species have evolved multiple strategies to ensure the onset of this critical behavior," the researchers write.

The findings further suggest that other behaviors that appear to be innate might involve some hidden learning too. And, what does it all mean for us humans?

"Human pheromones have not been conclusively identified and their existence remains controversial," Stowers says, although humans can pick up on signature scents. "If the mouse can effectively use this mechanism to release such an important behavior, it is possible that signature odors underlie the release of other apparently innate behaviors; in mouse or even humans."

When it comes to breastfeeding, on the other hand, "our knowledge that mouse and rabbit each use a different mechanism to initiate suckling leaves plenty of room for humans to use an entirely different mechanism as well."
Logan et al.: "Learned recognition of maternal signature odors mediates the first suckling episode in mice."

Cell Press

Related Behavior Articles from Brightsurf:

Variety in the migratory behavior of blackcaps
The birds have variable migration strategies.

Fishing for a theory of emergent behavior
Researchers at the University of Tsukuba quantified the collective action of small schools of fish using information theory.

How synaptic changes translate to behavior changes
Learning changes behavior by altering many connections between brain cells in a variety of ways all at the same time, according to a study of sea slugs recently published in JNeurosci.

I won't have what he's having: The brain and socially motivated behavior
Monkeys devalue rewards when they anticipate that another monkey will get them instead.

Unlocking animal behavior through motion
Using physics to study different types of animal motion, such as burrowing worms or flying flocks, can reveal how animals behave in different settings.

AI to help monitor behavior
Algorithms based on artificial intelligence do better at supporting educational and clinical decision-making, according to a new study.

Increasing opportunities for sustainable behavior
To mitigate climate change and safeguard ecosystems, we need to make drastic changes in our consumption and transport behaviors.

Predicting a protein's behavior from its appearance
Researchers at EPFL have developed a new way to predict a protein's interactions with other proteins and biomolecules, and its biochemical activity, merely by observing its surface.

Spirituality affects the behavior of mortgagers
According to Olga Miroshnichenko, a Sc.D in Economics, and a Professor at the Department of Economics and Finance, Tyumen State University, morals affect the thinking of mortgage payers and help them avoid past due payments.

Asking if behavior can be changed on climate crisis
One of the more complex problems facing social psychologists today is whether any intervention can move people to change their behavior about climate change and protecting the environment for the sake of future generations.

Read More: Behavior News and Behavior Current Events is a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for sites to earn advertising fees by advertising and linking to