What
makes for good dads?
We have all experienced a mother’s
unconditional love. What about our dads? Some of us have fathers who lend a
helping hand in the kitchen, have polished our school shoes at night, made a
cozy bed and put us to sleep. And then there are those in
the opposite gang who leave everything for our mothers to do. Have we ever
thought what makes dads good, more caring, and affectionate. And what could
transform a ‘normal’ dad into one who kisses, hugs, and cuddles- just like mom!
Scientists at the HarvardUniversity,
and Novartis Institutes for Biomedical
Research, Cambridge, USA, seem to have an answer to these queries.
With fascinating experiments in mice, they know what makes for good dads in
these tiny creatures.
Young mice (called pups) depend on
parental care to survive, just like humans. Mothers invariably take good care
of pups while that from the fathers varies with species. Both sexes in some
species of rodents like the Oldfield mice share parenting duties equally. In
other related species like the Deer mouse, fathers contribute minimally to
loving and raising pups.
Not just parenting habits, the two
species also differ in their habitats. Oldfield mice are found in extreme harsh
environments such as arid deserts and cloud forests. They live in small
family-like groups, and seem to have adapted to their sparse environments by
forming loving pair bonds, with both sexes sharing duties of parental care. The
deer mice on the other hand, are widespread in their distribution and have a
casual mating system.
Interestingly, both these species
can interbreed and produce viable babies in the lab. This implies that
scientists can use these animals to make a mixed family. Make babies that are
half-oldfield and half-deer. It can also help them determine if the environment
shapes a father’s behavior.
The Deer mice (left) do not build
nests, and fathers offer minimal care. Oldfield mice on the contrary (right)
build nests, and both the mother and father take care of the young ones. Pups
are seen in bright red color lying under the mother.
How do you know which mouse is a
good dad? You can’t ask the pups, right? So how is that done?
Scientists do that quite
fashionably. They give the breeding mice pair a home cage, lots of cotton to
build a cozy resting place called nest, and observe their parental behavior.
They measure parental care by
observing how fathers approach pups, move them with their front paws, lick
them, huddle over them, and change their position to provide more comfort. This
is done with the help of cameras that work day and night. The findings are
published in Nature.
Scientists observe that Oldfield
fathers offered care to the same extent as the mothers. The Deer mouse fathers
did not take care of the pups.
Are these differences genetic? Or is
it a result of how their dads loved them when they were kids? To address this
doubt, scientists performed cross-fostering experiments. Oldfield pups were
raised with deer fathers, and vice versa.
They found that the care a mouse
received when he was a kid had nothing to do with the kind of dad he would
become. This added weight to the possibility of a genetic link to being a good
dad. But wait, what if oldfield pups need more care then deer pups? They demand
it, so they get it. No, this isn’t the case either. Oldfield mice proved
themselves to be awesome dads, irrespective of who the kid was- their own
oldfield, or an adopted deer pup.
Hence, being a good dad is linked to
genes. Scientists dug deeper into which genes make oldfield mice good dads?
They found that the gene for vasopressin that controls
nest-building behavior is expressed differently in these two groups of mice.
Low vasopressin makes for good dads in mice!
With that information, can a
not-so-loving deer dad be transformed into an awesome oldfield father? Yes. It
can be done.
Inhibiting vasopressin neurons in
the brain increased nest-building behavior in deer dads too! Alternatively,
when high nest-building oldfield dads were given vasopressin injections in the
brain, they stopped making nests, confirming that it was vasopressin that made
them so different.
“Our genetic dissection of parenting opens new avenues of
research for the understanding of a complex social behavior. Discovering how
genes such as vasopressin may change specific aspects of behavior, will help
understand how behaviors and the brain evolve”, signs off Hopi E. Hoekstra,
Professor at the Howard Hughes Medical Institute, Harvard University,
Cambridge, USA.
By
Bhavya Khullar
