[Junior]

A 50 percent mortality rate would be nothing to sneeze at, either, and I'd think someone would've mentioned it (as well as mentioning that two-thirds of the population of Egypt had upped and left).

Still, Canaan could not support 1 million folks at this time, even if they managed to kill off all the locals first, which Scripture says they did not (there were the Philistines, remember).

[Asphalt]

Consider all the battles they were in. Seems reasonable to guess that many died. Consider other events (grounds opens up), also, just regualr everyday events- dehydration, getting trampled by a donkey, or whatever. I would guess the rate of birth dropped, and the rate of death increased. Over the period of 40+ years this would greatly reduce numbers.