Dan On 2/24/2011 11:32 AM, Don Ohmes wrote:
On 2/21/2011 8:24 PM, Tim Williams wrote:_Masiakasaurus_ was only 2m long, and has craniodental features (like procumbent front teeth) that suggest that it might have been a fish-eater. If correct, this in turn suggests that_Masiakasaurus_ habitually entered the water. Is this the kind of animal that could have given rise to a fully aquatic lineage of non-avian theropods? (Not_Masiakasaurus_ itself, given that it lived in the Maastrichtian.)I agree the questions should be asked, as you said earlier. But what would such a critter look like, and how would it get there?Could the arms be useful beyond a dog-paddle mode? Wouldn't penguin-style flapping require a _lot_ of re-arrangement?Granted, water seems a friendly place to do such alterations -- that is a path to flight rarely discussed, btw. Theropod becomes underwater swimmer becomes terrestrial cliff-diver or ridgesoarer, or some such cartoon...I think we talked briefly about water being where birds might done their 'pelvic re-arrangement' some years back.Another question -- why were/are even the flightless dino's so committed to nesting? Did some part of their reproductive process get so optimized early-on that _any_ mutation is critically maladaptive?