>>6495475already explained it to happy day so heres a copy/paste of it
well actually koalas have one of the smallest brain to body ratios out of mammals, and their brains are literally smooth so it lacks the surface area to conduct the same level of reactions that a wrinkled or well
a normal fucking brain could
they also have one of the biggest bowel to body ratios out of mammals cause they spend all of their energy fermenting eucalyptus so it's actually usable as food
they are literally so dumb that if you showed them a room with food in it and it wasnt hanging in a tree they'd starve cause they lack the essential wrinklyness of a normal brain
their cognitive thinking is so limited that they can only think about eucalyptus
so when im tired or if someone does something dumb
i like to call em smooth/small brained
or eucalyptus muncher if they're savvy enough to get that im still calling em a smooth brain
so
thats where smooth brain comes from
