I'd just like to offer thanks to NEEMAN, Ski, Divito, Mrs Peach, Roundy, et al. for "holding the fort" in my absence. Sorry I wasn't able to participate in this brilliant discussion over the last few days. I'm back in town now, with regular access to a computer, so I'll be back in the fray with all of you again in no time!
The issue is that our knowledge of evolution indicates that it is highly unlikely that two identical species would evolve separately on different continents, never mind several different species. Dogplatter's theory makes more sense.
We actually have a modern example of this - the Galapagos Islands. Over a relatively short amount of time, areas of isolation in which species do not colonise or migrate exhibit radically different patterns of evolution. Fossil evidence supports the maritime dinosaur hypothesis.
I said they have less brain function and then backed it up.
Listen, let's get one thing straight right now. There is NO WAY that a skull cavity alone can give any realistic indication of the intelligence of a particular species of animal. The correlation between size and intelligence is rough at very best, and has much more to do with particulars of homeostasis, locomotion and other factors unrelated to intelligence. The prefrontal cortex is the area of the brain which most contributes towards complex cognition, and it's impossible to measure even the physical size (let alone the actual mental capacity, which probably has little or no relation to the aforementioned) of a dinosaur's prefrontal cortex unless you can present a medical expert with a cryogenically frozen dinosaur brain. Good luck with that one.
Back to you sucking at debating.
NO SHIT I MADE A CLAIM AND NO SHIT YOU SAID YOU DIDN'T AND THEN YOU NEVER BACKED IT UP. DO YOU UNDERSTAND ANYTHING?
Ok guys, enough of this nasty-talk. I haven't given out, as General Douchebag so succinctly put it, any "b7's" or indeed bAnythings in this thread yet, but if you keep slagging eachother off like this in what's supposed to be a serious discussion forum then I might be forced to take some kind of action. Keep it civil here - take your frustration to Angry Ranting.