How have elephants evolved over the last 50 million years?

I.E The biggest changes from their original common ancestor [50 million years ago, NOT the wooly mammoth]. Bigger ears and smaller body? Something like that. Please give me the two biggest changes.
How have elephants evolved over the last 50 million years?
Their tusks and trunks changed drastically.



this one isn't quite that old

http://www.copyrightexpired.com/Heinrich...
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