What contributed the most to human migration more than ten thousand years ago? sturdy boats were invented. another ice age occurred. a major volcano erupted in africa. a severe drought occurred.

The correct answer is - Another Ice Age occurred.

More than ten thousand years ago, the Earth was in an Ice Age faze. During this age, because of the lower level of the seas and because of the large ice masses, lots of land-bridges emerged. This land-bridges were used by the humans to migrate to new territories, and slowly but surely they did managed to colonize most of the world in this period of time.

bibliography and citations to credit the sources hope this you if not my deepest of apologize ^w^