bill@utastro.UUCP (William H. Jefferys) (09/14/85)
Cranks frequently quote others out of context to provide themselves with additional ammunition. A case in point: [Ted Holden] > Wann Langston, writing in the Feb. 81 issue of Scientific > American, had this to say about the Texas pterosaurs > (Quetzalcoatlus): > > "Aeronautical engineers quickly pointed out, however, that a > pterosaur with the shape of a pteranodon and a wingspan of > 15.5 meters might have weighed as much as 136 kilograms. It > would then have lacked the muscle power to maintain level > flight by flapping its wings. Moreover, the strength of the > wing bones would perhaps have been insufficient to bear the > stresses the wings would have had to endure. Of course, > Quetzalcoatlus Northropi did not have exactly the same > proportions of Pteranodon. Even so, an animal with a > wingspan of 15.5 meters would probably have been at or > beyond the engineering limits for a flying machine made of > muscles, tendons, and delicate, hollow bones." But the next paragraph, which was left out of Ted's article, says: "Unfortunately the precise length of the wing of *Quetzalcoatlus northropi* is still uncertain. It is known, however, that the metacarpal bone of the fourth finger was relatively longer in *Quetzalcoatlus* than it was in *Pteranodon* and that some of the other bones of this finger were substantially shorter. These differences suggest an adjusted calculation by which the wingspan of *Quetzalcoatlus* sp. emerges as no less than 5.5 meters, and that of *Q. northropi* as 11 to 12 meters. Such an animal might have weighed 86 kilograms. In spite of the recent discovery in Argentina of an extinct vulture whose wingspan is estimated to have been more than seven meters, *Q. northropi* still would rank as the largest known flying creature." By omitting the second paragraph, the impression is given that Langston believes *Q. northropi* to be much larger and heaver than he really does. It is also implied, falsely, that Langston believes *Q. northropi* could not fly. Now, we do not know whether this misquotation is original with Ted, or (as is highly likely) he got it in this form from another source. I sincerely hope the latter is the case, for whatever my opinion of Ted's theories, I do not want to think that he would deliberately engage in this dishonest and reprehensible tactic. Later in the article (p. 131), Langston goes on to explain how he believes *Q. northropi* became airborne: "It appears, then, that *Quetzalcoatlus* may have lived on fairly flat, low-lying ground. There, as is the habit of a vulture, it may well have had to wait each morning until the sun warmed the ground and strong thermal updrafts developed. In the larger pterosaurs the musculature that animated the wing was not impressively massive, and the hind limbs were long but weak. All things considered, it seems unlikely that *Quetzalcoatlus* could have run on its hind legs and flapped its wings energetically. Still, if the animal could stand up on its hind legs and catch the appropriate breeze, a single flap of the wings and a kick with the legs may have been all it needed for takeoff." Langston is not describing the same behemoth which flies by expending large amounts of power flapping its wings that Ted does. For a gliding animal such as Langston postulates, large amounts of wing power are not required, as the necessary lift comes from thermals. True, getting airborne is not easy, but Langston proposes a plausible mechanism, well known from living (though smaller) creatures. Once airborne there is no reason why *Quetzalcoatlus* could not have remained aloft all day, as unpowered sailplanes do today. In any case, Langston's article shows clearly that the following assertion Ted made is just not true: > Everybody who has ever studied pterosaurs and done any > THINKING about them has arrived at the same conclusion: that > it would be physically impossible for them to fly, but that > they obviously HAD to fly in order to survive (since they were > built for flying and could not have earned a living otherwise), > hence an enigma, And here Ted inserts a remark that is typical of the way that cranks grossly overestimate the importance of their ideas: > ...which I claim nothing other than Immanuel > Velikovsky's theory of a lesser FELT EFFECT of gravity in the > archaic world could possibly account for. Let me stress that the issue here is not whether Langston's conclusions about *Q. northropi* are correct or not; the issue is the improper use of one person's work by another. I hope that Ted will restrict any reply to this issue. -- Glend. I can call spirits from the vasty deep. Hot. Why, so can I, or so can any man; But will they come when you do call for them? -- Henry IV Pt. I, III, i, 53 Bill Jefferys 8-% Astronomy Dept, University of Texas, Austin TX 78712 (USnail) {allegra,ihnp4}!{ut-sally,noao}!utastro!bill (UUCP) bill@astro.UTEXAS.EDU. (Internet)