  We introduce a method that permits to co-evolve the body and the control
properties of robots. It can be used to adapt the morphological traits of
robots with a hand-designed morphological bauplan or to evolve the
morphological bauplan as well. Our results indicate that robots with co-adapted
body and control traits outperform robots with fixed hand-designed
morphologies. Interestingly, the advantage is not due to the selection of
better morphologies but rather to the mutual scaffolding process that results
from the possibility to co-adapt the morphological traits to the control traits
and vice versa. Our results also demonstrate that morphological variations do
not necessarily have destructive effects on robot skills.
