>> Being a biped allow you to carry things in, your arms while travelling.

>ah. yes. like a baby, I guess.

you read my mind because i was thinking about babies among other
things when
i wrote.( i thought about hugging too and touching, with the evident
carrying of animal body)

The fact of the human baby  being one of the most  helpless mammal at
birth
and who  have the  longest maturation time , has  certaily many
impacts on
feeding patterns of humans .And becoming a biped is a clear advantage
to
transport the food to the mother instead of her having to search  for
herself.

The baby have to be holded ( before the invention of slings) not alike
the
other primates who hold on the fur

primates need their 4 hands to climb trees,  humans can send the young
male.to bring back to the group

jean-claude.