Guns, Germs, and Steal... again

Jared Diamond is trying to answer the question why New Guinea is so undeveloped even though they started farming around the same time as China, the Middle East and Central America.  He believes its because they do not have very geographical luck.  The climate they live in is not fit for growing crops.  He has a feeling though that this cannot be the only reason the world is divided into haves and have nots.  There is something else causing  it too.  A new reason he discovered is animal herding.  People start domesticating animals and using them for food, milk, and fur.  Animals were starting to become a big part of the worlds civilization.  Also, people starting using horses and oxes to plow for them to help their crops grow.  There are still no farm animals (besides pigs) in new Guinea to help them with things like that.  the only muscle power they have human muscle.  The best animal to domesticate is a large plant eating animal.  There are 48 animals that can be domesticated.  Only 14 have been used.  Some domesticated animals are goats sheep pigs, cows horses donkeys, camals, water buffalo, mithan.