from École Polytechnique Fédérale de Lausanne (EPFL) and the Université de
Lausanne in Switzerland have used simple robots to study the evolution of
altruism in social animals.
Floreano, study leader and EPFL robotics professor, and Laurent Keller, a
biologist from the Université de Lausanne, have joined forces to study how
altruism came about in social creatures that were born to understand
"survival of the fittest."
is the selfless concern for the welfare of others. It is demonstrated in
animals like worker ants, which are sterile and give up the transmission of
their own genes in order to guarantee the survival of the queen's genetic
makeup. This type of altruism is known as kin selection, where the individual
makes personal sacrifices in order to insure the survival of a relative's
a biologist named W.D. Hamilton proposed that if an individual member shares
food with its family, it decreases its own survival yet increases the chance of
survival for family members that can pass along family genes. Hamilton's rule
of kin selection states that an organism is more likely to share its food with
another that is genetically close rather than those who are not.
and Keller began experimenting with this theory using robots. In previous
studies, the robots would perform simple tasks like pushing seed-like objects
across the floor to specific destinations. The robots would evolve over several
generations, and those that could not push the objects to the correct
destination were pulled from the study, unable to pass their code along. On the
other hand, robots that were able to perform the desired task were allowed to
pass their code on, and this code was mutated and recombined with other robots in
the next generation.
Floreano and Keller are testing the evolution of altruism through the use of
robots that evolve quickly. The robots are able to evolve through
the use of simulated gene and genome functions. Some robots are created as
clones, siblings, cousins, and complete strangers. The difference between this
new study and the older ones is that robots now have the option to share a seed
once it is pushed to the desired destination. Over the course of 500
generations of experiments, the researchers observed when robots would share,
when they wouldn't, and what the consequences were for both options.
results of the study showed that Hamilton's rule of kin selection was exactly
right. Groups of robots that were related shared the seed, and the family
became strong and was able to pass its code to the next generation. Hamilton's
original theory takes into account both a limited and isolated vision of gene
interaction while these gene simulations in robots "integrate effects of
one gene in multiple other genes," and Hamilton's theory was still
have been able to take this experiment and extract an algorithm that we can use
to evolve cooperation in any type of robot," said Floreano. "We are
using this altruism algorithm to improve the control system of our flying
robots and we see that it allows them to effectively collaborate and fly in swarm formation more
study was published in PLoS Biology.