The Molecule of More

THE MOLECULE OF MORE

SURVIVAL OF THE FITTEST

Maybe the migratory tribes left for some other reason that had noth-
ing  to  do  with novelty-seeking. Maybe they  left  because of conflict, or 
perhaps they were hunting migratory animals. There could have been
many reasons unrelated to dopamine, but the question remains: Under
these circumstances, why would the migratory population end up with
lots of 7R alleles among its members? The answer is that maybe the 7R
allele didn’t set  off  the  migration, but  once it  began, the  allele gave its 
carriers a survival advantage.
One advantage provided by the 7R allele is that it drove its carri-
ers to explore the new environment in which they found themselves in
order to seek  out  opportunities to  maximize resources. In  other words, 
it promoted novelty-seeking. For example, a tribe might have started
out in a geographical area where there was a consistent climate, and
the same type of food was available all year round. However, after mov-
ing to a new location, the members of the migratory tribe may have
experienced rainy and dry seasons, and they needed to learn how to
switch food sources as the seasons changed. Figuring out how to do that
involved risk-taking and experimentation.
There’s also evidence that people who carry the 7R allele are
faster learners, especially when getting the answer right triggers a
reward. In general, 7R carriers are more sensitive to rewards; they
have stronger reactions to both wins and losses. Consequently, when
they found themselves in an unfamiliar environment and needed to
adapt to new routines to stay alive, the 7R carriers worked harder to
figure things out because their experiences of success and  failure were
more intense.
Another advantage is that the 7R allele is associated with some-
thing called low reactivity to novel stressors. Change is stressful—both good
change and bad change. For example, there are few things more stress-
ful than divorce, but getting married is hard, too. Going bankrupt is
stressful but so is winning the lottery. Bad changes may cause more
stress than good changes, but  the  most important factor is  the  size  of 
the change. Bigger change means more stress.