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Re: emu invasion

----- Original Message ----- From: "Tommy Tyrberg" <tommy.tyrberg@norrkoping.mail.telia.com>
To: <jbois@verizon.net>; <dinosaur@usc.edu>
Sent: Sunday, January 04, 2009 2:46 PM
Subject: SV: emu invasion

Emus back in Oz survive predation by dingoes and presumably by
thylacines, Sarcophilus and Thylacoleo in the past. Coyotes probably
aren't that much more efficient predators than dingoes.
And yet...I am still surprised at their success in North America. The diversity of large flightless birds is so low, one wonders at the success of the body plan in any location (except predatorless islands, of course--was it eleven or so species of moa on NZ before man?). And in almost all continental ratites, success seems dependent upon arid grassy habitat (presumably its value lies in providing good nesting cover at low predator density). In that sense, Texas may be perfect...a home away from home.coyotered wolf gray wolf red fox gray fox black bear ringtail raccoon weasels spotted skunks striped skunk hog-nosed skunk (Homotherium and Smilodon) are not estimated because there are no closely related extant taxa to serve as analogs. Median weights and estimates for modern and extinct carnivores are listed in Table 3.1. Average weights of the predator guild per temporal puma or cougar margay bobcat jaguar extinct dire wolf extinct North American lionswift fox grizzly bear
But whereas in Australia the emu has little to worry about outside the dingo, in Texas they have to deal with coyote, red fox, gray fox, raccoon, weasel, spotted, striped, and hog-nosed skunks, and bobcats; and in recent history they would also have had wolves. Indeed, any ratite trying to make a go of it in the Texas of prehistoric times would apply for instant repatriation back to Oz when it took one look at a dire wolf or an American lion. However, just as in Australia where emus thrive inside a vast fence designed to keep the bloody dingoes out, they may make it in Texas thanks to aggressive predator extirpation.