Relay-Version: version B 2.10 5/3/83; site utzoo.UUCP Posting-Version: version B 2.10.2 9/18/84; site cybvax0.UUCP Path: utzoo!linus!philabs!cmcl2!seismo!harvard!think!mit-eddie!cybvax0!mrh From: mrh@cybvax0.UUCP (Mike Huybensz) Newsgroups: net.origins Subject: Re: more on 250 lb. birds Message-ID: <690@cybvax0.UUCP> Date: Tue, 20-Aug-85 10:27:20 EDT Article-I.D.: cybvax0.690 Posted: Tue Aug 20 10:27:20 1985 Date-Received: Fri, 23-Aug-85 06:14:42 EDT References: <375@imsvax.UUCP> Reply-To: mrh@cybvax0.UUCP (Mike Huybensz) Organization: Cybermation, Inc., Cambridge, MA Lines: 19 Without checking articles on Pteratorns, there are still a great number of reasons for rejecting the low-gravity hypothesis. First, the physical limits referred to for mass of flying birds were calculated for SUSTAINED POWERED FLIGHT. As human glider and hang-glider pilots can tell you, they don't say much about limits of unpowered flight using thermals and updrafts (which, by the way, is how most large predatory birds sustain their extended flight.) Second, if lower gravity had existed, it would have had MANY more effects than just two or three unusually large animals. Sedimentation, waves, vegetation, and a host of other fossil evidence would have been quite different. Instead, we find fossilized trees with normal amounts of support tissues, and no bigger than today's redwoods (which would probably also be cited as evidence of low gravity and lack of disease or aging if they were known only from fossils. :-) -- Mike Huybensz ...decvax!genrad!mit-eddie!cybvax0!mrh