The difference in the size of the ears is interesting. Probably a climate adaptation. Although the Indian elephant, not shown, has disproportionately smaller ears than the African elephant which is a larger beast, I would suspect it's not much cooler in India.
Speaking of climate, it is even more interesting to speculate why these beasts disappeared from North America about 11,000 years ago. The Wikipedia article cites the possibility that humans hunted them to extinction but seems to lean toward the view that climate change-global warming 11,000 years ago-led to their extinction.
