Pronghorns.

Here's a little info about Texas pronghorn antelope--

http://www.tpwd.state.tx.us/landwater/land/habitats/trans_pecos/big_game/pronghorn/

http://alpinedailyplanet.typepad.com/alpine-daily-planet/2010/12/trans-pecos-group-addresses-crisis-in-pronghorn-antelope-population.html

I was trying to load some pictures but it's not happening >.<

I want to say I read somewhere that they really aren't antelope, but I scanned so much stuff, and I'm not finding that now. I'll do more research tonight.