quote:

ORIGINAL: Musicmystery

"Show" isn't an improvement on "prove" -- more accurately, science indicates, through testing hypotheses, what seems to work -- and in "established" science, seems to work so well that we can accurately use it at a practical level . . . like electricity uses electrons. But science knows that new information could come along (and regularly does) that shows our understanding was too basic and is in fact in error, because a better explanation came along that explains more things and stands up to testing.

That evolution happened is pretty well established. You really have to tap dance to brush away the geologic record in particular, usually by turning to the Perfectionist Fallacy. If there's a better explanation, it's going to be remarkable.

Sue, some things are certain -- like where the north pole is, but shifts also shift, like where the magnetic pole is, so we keep observing and testing. We know things fall, but gravity is still poorly understood. So physics keep working on it. What they don't do is say (as people used to a one time) that angels push us down to the earth.

But your chanting your mantra about evolution as godless religion is just silly. Repeating something only makes it true in your own mind. There's nothing there that threatens god except in the minds of those who insist (on poor evidence) that every word in the Bible is literally true, so god created the world in 6 days -- despite evidence showing that's not how it happened, god or no.

You are simply promoting your own belief, and mischaracterizing science in the process. Science doesn't give a damn what anyone believes, including the scientist. The tests will show what they show, and the scientist will learn from the results, form new hypotheses, test those, etc. -- it's mode of inquiry, a way of learning, not a wholesale acceptance of dogma.

From a logic standpoint, it's as simple as the difference between inductive and deductive reasoning. Science is inductive, and therefore, the conclusions are never inescapable (though they can be damn likely given what we know so far).

Rather than a weakness or a belief, that's the strength of science -- it assumes we have more to learn, and the arbiter isn't personal or group belief, but the results of testing through careful and replicable methodology. Belief is irrelevant, and to be proven wrong (where we can have certainty) is to learn and to expand knowledge.

quote:

ORIGINAL: Musicmystery

Sounds to me like you talk to "evolutionists" who also don't understand what science is.

AT the same time, so say it's not "proven" isn't the same as the reality that the evidence that evolution occurred is strong. How it happened is a more varied matter.

FFS, even Genesis shows God creating the world in stages, with man last.

quote:

ORIGINAL: Musicmystery

Sex, Drugs, Disasters, and the Extinction of Dinosaurs by Stephen Jay Gould

Science, in its most fundamental definition, is a fruitful mode of inquiry, not a list of enticing conclusions. The conclusions are the consequence, not the essence.

My greatest unhappiness with most popular presentations of science concerns their failure to separate fascinating claims from the methods that scientists use to establish the facts of nature. Journalists, and the public, thrive on controversial and stunning statements. But science is, basically, a way of knowing—in P.B. Medawar’s apt words, “the art of the soluble.” If the growing corps of popular science writers would focus on how scientists develop and defend those fascinating claims, they would make their greatest possible contribution to public understanding.

Consider three ideas, proposed in perfect seriousness to explain that greatest of all titillating puzzles—the extinction of dinosaurs. Since these three notions invoke the primally fascinating themes of our culture—sex, drugs, and violence—they surely reside in the category of fascinating claims. I want to show why two of them rank as silly speculation, while the other represents science at its grandest and most useful.

Science works with testable proposals. If, after much compilation and scrutiny of data, new information continues to affirm a hypothesis, we may accept it provisionally and gain confidence as further evidence mounts. We can never be completely sure that a hypothesis is right, though we may be able to show with confidence that it is wrong. The best scientific hypotheses are also generous and expansive; they suggest extensions and implications that enlighten related, and even far distance, subjects. Simply consider how the idea of evolution has influenced virtually every intellectual field.

Useless speculation, on the other hand, is restrictive. It generates no testable hypothesis, and offers no way to obtain potentially refuting evidence. Please note that I am not speaking of truth or falsity. The speculation may well be true; still, if it provides, in principle, no material for affirmation or rejection, we can make nothing of it. It must simply stand forever as an intriguing idea. Useless speculation turns in on itself and leads nowhere; good science, containing both seeds for its potential refutation and implications for more and different testable knowledge, reaches out. But, enough preaching. Let’s move on to the dinosaurs, and the three proposals for their extinction.

1. Sex: Testes function only in a narrow range of temperature. (Those of mammals hang externally in a scrotal sac because internal body temperatures are too high for their proper function.) A worldwide rise in temperature at the close of the Cretaceous period caused the testes of dinosaurs to stop functioning and led to their extinction by sterilization of males.

2. Drugs: Angiosperms (flowering plants) first evolved toward the end of the dinosaurs’ reign. Many of these plants contain psychoactive agents, avoided by mammals today as a result of their bitter taste. Dinosaurs had neither means to taste the bitterness nor livers
effective enough to detoxify the substances. They died of massive overdoses.

3. Disasters: A large comet or asteroid struck the earth some 65 million years ago, lofting a cloud of dust into the sky and blocking sunlight, thereby suppressing photosynthesis and so drastically lowering world temperatures that dinosaurs and hosts of other creatures
became extinct.

Before analyzing these three tantalizing statements, we must establish a basic ground rule often violated in proposals for the dinosaurs’ demise. There is no separate problem of the extinction of the dinosaurs. Too often we divorce specific events from their wider contexts and systems of cause and effect. The fundamental fact of dinosaur extinction is its synchrony with the demise of so many other groups across a wide range of habitats, from terrestrial to marine.

The history of life has been punctuated by brief episodes of mass extinction. A recent analysis by University of Chicago paleontologists Jack Sepkoski and Dave Raup, based on the best and most exhaustive tabulation of data ever assembled, shows clearly that five episodes of mass dying stand well above the “background” extinctions of normal times (when we consider all mass extinctions, large and small, they seem to fall in a regular 26-million-year cycle...). The Cretaceous debacle, occurring 65 million years ago and separating the Mesozoic and Cenozoic eras of our geological time scale, ranks prominently among the five. Nearly all the marine plankton (single-celled floating creatures) died with geological suddenness; among marine invertebrates, nearly 15 percent of all families perished, including many previously dominant groups, especially the ammonites (relatives of squids in coiled shells). On land, the dinosaurs disappeared after more than 100 million years of unchallenged domination.

In this context, speculations limited to dinosaurs alone ignore the larger phenomenon. We need a coordinated explanation for a system of events that includes the extinction of dinosaurs as one component. Thus it makes little sense, though it may fuel our desire to view mammals as inevitable inheritors of the earth, to guess that dinosaurs died because small mammals ate their eggs (a perennial favorite among untestable speculations). It seems most unlikely that some disaster peculiar to dinosaurs befell these massive beasts—and that the debacle happened to strike just when one of history’s five great dyings had enveloped the earth for completely different reasons.

The testicular theory, an old favorite from the 1940s, had its root in an interesting and thoroughly respectable study of temperature tolerances in the American alligator, published in the staid Bulletin of the American Museum of Natural History on 1946 by three experts on living and fossil reptiles—E.H. Colbert, my own first teacher in paleontology; R.B. Cowles; and C.M. Bogert.

The first sentence of their summary reveals a purpose beyond alligators: “This report describes an attempt to infer the reactions of extinct reptiles, especially the dinosaurs, to high temperatures as based upon reactions observed in the modern alligator.” They studied, by rectal thermometry, the body temperatures of alligators under changing conditions of heating and cooling. (Well let’s face it, you wouldn’t want to try sticking a thermometer under a ‘gator’s tongue.) The predictions under test go way back to an old theory first stated by Galileo in the 1630s—the unequal scaling of surfaces and volumes. As an animal, or any object, grows (provided its shape doesn’t change), surface areas must increase more slowly than volumes— since surfaces get larger as length squared, while volumes increase much more rapidly, as length cubed. Therefore, small animal have high ratios of surface to volume, while large animals cover themselves with relatively little surface.

Among cold-blooded animals lacking any physiological mechanism for keeping their temperatures constant, small creatures have a hell of a time keeping warm—because they lose so much heat through their relatively large surfaces. On the other hand, large animals, with their relatively small surfaces, may lose heat so slowly that, once warm, they may maintain effectively constant temperatures against ordinary fluctuations of climate. In fact, the resolution of the “hot- blooded dinosaur” controversy that burned so brightly a few years back may simply be that, while large dinosaurs possessed no physiological mechanism for constant temperature, and were not therefore warm-blooded in the technical sense, their large size and relatively small surface area kept them warm.

Colbert, Cowles, and Bogert compared the warming rates of small and large alligators. As predicted, the small fellows heated up (and cooled down) more quickly. When exposed to a warm sun, a tiny 50-gram (1.76 ounce) alligator heated up one degree Celsius every minute and a half, while a large alligator, 260 times bigger at 13,000 grams (28.7 pounds), took seven and a half minutes to gain a degree. Extrapolating up to an adult 10-ton dinosaur, they concluded that a one-degree rise in body temperature would take eighty-six hours. If large animals absorb heat so slowly (through their relatively small surfaces), they will also be able to shed any excess heat gained when temperatures rise above a favorable level.

The authors then guessed that large dinosaurs lived at or near their optimum temperatures. Cowles suggested that a rise in global temperatures just before the Cretaceous extinction caused the dinosaurs to heat up beyond their optimal tolerance—and, being so large, they couldn’t shed the unwanted heat. (In a most unusual statement within a scientific paper, Colbert and Bogert then explicitly disavowed this speculative extension of their empirical work on alligators.) Cowles conceded that this excess heat probably wasn’t enough to kill or even to enervate the great beasts, but since testes often function within a narrow range of temperature, he proposed that this global rise might have sterilized all the males, causing extinction by natural contraception.
The overdose theory has recently been supported by UCLA psychiatrist Ronald K. Siegel. Siegel has gathered, he claims, more than 2,000 records of animals who, when given access, administer various drugs to themselves—from a mere swig of alcohol to massive doses of the big H. Elephants will swill the equivalent of twenty beers at a time, but do not like alcohol in concentrations greater than 7 percent. In a silly bit of anthropocentric speculation, Siegel states that “elephants drink, perhaps, to forget...the anxiety produced by shrinking rangeland and the competition for food.”

Since fertile imaginations can apply almost any hot idea to the extinction of dinosaurs, Siegel found a way. Flowering plants did not evolve until late in the dinosaurs’ reign. These plants also produced an array of aromatic, amino-acid-based alkaloids—the major group of psychoactive agents. Most mammals are “smart” enough to avoid these potential poisons. The alkaloids simply don’t taste good (they are bitter); in any case, we mammals have livers happily supplied with the capacity to detoxify them. But, Siegel speculates, perhaps dinosaurs could neither taste the bitterness nor detoxify the substances once ingested. He recently told members of the American Psychological Association: “I’m not suggesting that all dinosaurs OD’d on plant drugs, but it certainly was a factor.” He also argued that death by overdose may help explain why so many dinosaur fossils are found in contorted positions. (Do not go gentle into that good night.)

Extraterrestrial catastrophes have long pedigrees in the popular literature of extinction, but the subject exploded again in 1979, after a long lull, when the father-son, physicist-geologist team of Luis and Walter Alvarez proposed that an asteroid, some 10 km in diameter, struck the earth 65 million years ago.
The force of such a collision would be immense, greater by far than the megatonnage of all the world’s nuclear weapons. In trying to reconstruct a scenario that would explain the simultaneous dying of dinosaurs on land and so many creatures in the sea, the Alvarezes proposed that a gigantic dust cloud, generated by particles blown aloft in the impact, would so darken the earth that photosynthesis would cease and temperatures drop precipitously. (Rage, rage against the dying of the light.) The single-celled photosynthetic oceanic plankton, with life cycles measured in weeks, would perish outright, but land plants might survive through the dormancy of their seeds (land plants were not much affected by the Cretaceous extinction, and any adequate theory must account for the curious pattern of differential survival). Dinosaurs would die by starvation and freezing; small, warm-blooded mammals, with more modest requirements for food and better regulation of body temperature, would squeak through. “Let the bastards freeze in the dark,” as bumper stickers of our chauvinistic neighbors in sunbelt states proclaimed several years ago during the Northeast’s winter oil crisis.

All three theories, testicular malfunction, psychoactive overdosing, and asteroidal zapping, grab our attention mightily. As pure phenomenology, they rank about equally high on the hit parade of primal fascination. Yet one represents expansive science, the others restrictive and untestable speculation. The proper criterion lies in evidence and methodology; we must probe behind the superficial fascination of particular claims.

How could we possible decide whether the hypothesis of testicular frying is right or wrong? We would have to know things that the fossil record cannot provide. What temperatures were optimal for dinosaurs? Could they avoid the absorption of excess heat by staying in the shade, or in caves? At what temperatures did their testicles cease to function? Were late Cretaceous climates ever warm enough to drive the internal temperatures of dinosaurs close to this ceiling? Testicles simply don’t fossilize, and how could we infer their temperature tolerances even if they did? In short, Cowles’s hypothesis is only an intriguing speculation leading nowhere. The most damning statement against it appeared right at the conclusion of Colbert, Cowles, and Bogert’s paper, when they admitted: “It is difficult to advance any definite arguments against this hypothesis.” My statement may seem paradoxical—isn’t a hypothesis really good if you can’t devise any arguments against it? Quite the contrary. It is untestable and unusable.

Siegel’s overdosing has even less going for it. At least Cowles extrapolated his conclusion from some good data on alligators. And he didn’t completely violate the primary guideline of siting dinosaur extinction in the context of a general mass dying—for rise in temperature could be the root cause of a general catastrophe, zapping dinosaurs by testicular malfunction and different groups for other reasons. But Siegel’s speculation cannot touch the extinction of ammonites or oceanic plankton (diatoms make their own food with good sweet sunlight; they don’t OD on the chemicals of terrestrial plants). It is simply a gratuitous, attention-grabbing guess. It cannot be tested, for how can we know what dinosaurs tasted and what their livers could do? Livers don’t fossilize any better than testicles.

The hypothesis doesn’t even make any sense in its own context. Angiosperms were in full flower ten million years before dinosaurs went the way of all flesh. Why did it take so long? As for the pains of a chemical death recorded in contortions of fossils, I regret to say (or rather I’m pleased to note for the dinosaurs’ sake) that Siegel’s knowledge of geology must be a bit deficient; muscles contract after death and geological strata rise and fall with motions of the earth’s crust after burial—more than enough reason to distort a fossil’s pristine appearance.

The impact story, on the other hand, has a sound basis in evidence. It can be tested, extended, refined and, if wrong, disproved. The Alvarezes did not just construct an arresting guess for public consumption. They proposed their hypothesis after laborious geochemical studies with Frank Asaro and Helen Michel had revealed a massive increase of iridium in rocks deposited right at the time of the extinction. Iridium, a rare metal of the platinum group, is virtually absent from indigenous rocks of the earth’s crust; most of our iridium arrives on extraterrestrial objects that strike the earth.
The Alvarez hypothesis bore immediate fruit. Based originally on evidence from two European localities, it led geochemists throughout the world to examine other sediments of the same age. They found abnormally high amounts of iridium everywhere—from continental rocks of the western United States to deep sea cores from the South Atlantic.

Cowles proposed his testicular hypothesis in the mid-1940s. Where has it gone since then? Absolutely nowhere, because scientists can do nothing with it. The hypothesis must stand as a curious appendage to a solid study of alligators. Siegel’s overdose scenario will also win a few press notices and fade into oblivion. The Alvarezes’ asteroid falls into a different category altogether, and much of the popular commentary has missed this essential distinction by focusing on the impact and its attendant results, and forgetting what really matters to a scientist—the iridium. If you talk just about asteroids, dust and darkness, you tell stories no better and no more entertaining than fried testicles or terminal trips. It is the iridium—the source of testable evidence—that counts and forges the crucial distinction between speculation and science.

The proof, to twist a phrase, lies in the doing. Cowles’s hypothesis has generated nothing in thirty-five years. Since its proposal in 1979, the Alvarez hypothesis has spawned hundreds of studies, a major conference, and attendant publications. Geologists are fired up. They are looking for iridium at all other extinction boundaries. Every week exposes a new wrinkle in the scientific press. Further evidence that the Cretaceous iridium represents extraterrestrial impact and not indigenous volcanism continues to accumulate. As I revise this essay in November 1984, new data include chemical “signatures” of other isotopes indicating unearthly provenance, glass spherules of a size and sort produced by impact and not by volcanic eruptions, and high-pressure varieties of silica formed (so far as we know) only under the tremendous shock of impact.

My point is simply this: Whatever the eventual outcome (I suspect it will be positive), the Alvarez hypothesis is exciting, fruitful science because it generates tests, provides us with things to do, and expands outward. We are having fun, battling back and forth, moving toward a resolution, and extending the hypothesis beyond its original scope (see “The Cosmic Dance of Siva” for some truly wondrous extensions).
As just one example of the unexpected, distant cross-fertilization that good science engenders, the Alvarez hypothesis made a major contribution to a theme that has riveted public attention in the past few months—so-called nuclear winter. In a speech delivered in April 1982, Luis Alvarez calculated the energy that a ten-kilometer asteroid would release on impact. He compared such an explosion with a full nuclear exchange and implied that all-out nuclear war might unleash similar consequences.

The theme of impact leading to massive dust clouds and falling temperatures formed an important input to the decision of Carl Sagan and a group of colleagues to model the climatic consequences of nuclear holocaust. Full nuclear exchange would probably generate the same kind of dust cloud and darkening that may have wiped out the dinosaurs. Temperatures would drop precipitously and agriculture might become impossible. Avoidance of nuclear war is fundamentally an ethical and political imperative, but we must know the factual consequences to make firm judgments. I am heartened by a final link across disciplines and deep concerns— another criterion, by the way, of science at its best: A recognition of the very phenomenon that made our evolution possible by exterminating the previously dominant dinosaurs and clearing a way for the evolution of large mammals, including us, might actually help to save us from joining those magnificent beasts in contorted poses among the strata of the earth.

From The Flamingo’s Smile (1985, W. W. Norton and Company) Originally published in Discover Magazine, Time Inc., 1984


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ORIGINAL: Milesnmiles

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ORIGINAL: Musicmystery

"Show" isn't an improvement on "prove" -- more accurately, science indicates, through testing hypotheses, what seems to work -- and in "established" science, seems to work so well that we can accurately use it at a practical level . . . like electricity uses electrons. But science knows that new information could come along (and regularly does) that shows our understanding was too basic and is in fact in error, because a better explanation came along that explains more things and stands up to testing.

That evolution happened is pretty well established. You really have to tap dance to brush away the geologic record in particular, usually by turning to the Perfectionist Fallacy. If there's a better explanation, it's going to be remarkable.

Sue, some things are certain -- like where the north pole is, but shifts also shift, like where the magnetic pole is, so we keep observing and testing. We know things fall, but gravity is still poorly understood. So physics keep working on it. What they don't do is say (as people used to a one time) that angels push us down to the earth.

But your chanting your mantra about evolution as godless religion is just silly. Repeating something only makes it true in your own mind. There's nothing there that threatens god except in the minds of those who insist (on poor evidence) that every word in the Bible is literally true, so god created the world in 6 days -- despite evidence showing that's not how it happened, god or no.

You are simply promoting your own belief, and mischaracterizing science in the process. Science doesn't give a damn what anyone believes, including the scientist. The tests will show what they show, and the scientist will learn from the results, form new hypotheses, test those, etc. -- it's mode of inquiry, a way of learning, not a wholesale acceptance of dogma.

From a logic standpoint, it's as simple as the difference between inductive and deductive reasoning. Science is inductive, and therefore, the conclusions are never inescapable (though they can be damn likely given what we know so far).

Rather than a weakness or a belief, that's the strength of science -- it assumes we have more to learn, and the arbiter isn't personal or group belief, but the results of testing through careful and replicable methodology. Belief is irrelevant, and to be proven wrong (where we can have certainty) is to learn and to expand knowledge.

Okay, since you keep insisting that I don't understand science and you seem to like to define what science is for us, let's look at what you have to say.
Which is closer to agreeing with what you say science is;
My statement, from someone who "doesn't understand science"; that at best science "shows" that evolution could be true or your statement; "that evolution happened is pretty well established".
Sure. But "at best" here means that the evidence indicates the hypothesis holds up consistently. That's pretty solid. Unless you've got a better supported alternative.

Which one seems to be a "belief" in something
No, that's silly. "All the evidence suggests this is true" certainly rises above a mere belief. In fact, when I believe something, and I find the evidence shows something else, I recognize that my belief was false.

and seems to show they have stopped assuming "we have more to learn"?
No. That we could always potentially undercover new information doesn't mean we haven't learned so far, or that we think we now know everything.

In fact, studies of evolution continue to the present day.

quote:

ORIGINAL: Musicmystery

I think you need to learn a bit more about the subject instead of continuing with "Nuh-uh."

These aren't "my" definitions of science. Or evolution.

Read this. It will help:

quote:

ORIGINAL: Musicmystery

Sex, Drugs, Disasters, and the Extinction of Dinosaurs by Stephen Jay Gould

Science, in its most fundamental definition, is a fruitful mode of inquiry, not a list of enticing conclusions. The conclusions are the consequence, not the essence.

My greatest unhappiness with most popular presentations of science concerns their failure to separate fascinating claims from the methods that scientists use to establish the facts of nature. Journalists, and the public, thrive on controversial and stunning statements. But science is, basically, a way of knowing—in P.B. Medawar’s apt words, “the art of the soluble.” If the growing corps of popular science writers would focus on how scientists develop and defend those fascinating claims, they would make their greatest possible contribution to public understanding.

Consider three ideas, proposed in perfect seriousness to explain that greatest of all titillating puzzles—the extinction of dinosaurs. Since these three notions invoke the primally fascinating themes of our culture—sex, drugs, and violence—they surely reside in the category of fascinating claims. I want to show why two of them rank as silly speculation, while the other represents science at its grandest and most useful.

Science works with testable proposals. If, after much compilation and scrutiny of data, new information continues to affirm a hypothesis, we may accept it provisionally and gain confidence as further evidence mounts. We can never be completely sure that a hypothesis is right, though we may be able to show with confidence that it is wrong. The best scientific hypotheses are also generous and expansive; they suggest extensions and implications that enlighten related, and even far distance, subjects. Simply consider how the idea of evolution has influenced virtually every intellectual field.

Useless speculation, on the other hand, is restrictive. It generates no testable hypothesis, and offers no way to obtain potentially refuting evidence. Please note that I am not speaking of truth or falsity. The speculation may well be true; still, if it provides, in principle, no material for affirmation or rejection, we can make nothing of it. It must simply stand forever as an intriguing idea. Useless speculation turns in on itself and leads nowhere; good science, containing both seeds for its potential refutation and implications for more and different testable knowledge, reaches out. But, enough preaching. Let’s move on to the dinosaurs, and the three proposals for their extinction.

1. Sex: Testes function only in a narrow range of temperature. (Those of mammals hang externally in a scrotal sac because internal body temperatures are too high for their proper function.) A worldwide rise in temperature at the close of the Cretaceous period caused the testes of dinosaurs to stop functioning and led to their extinction by sterilization of males.

2. Drugs: Angiosperms (flowering plants) first evolved toward the end of the dinosaurs’ reign. Many of these plants contain psychoactive agents, avoided by mammals today as a result of their bitter taste. Dinosaurs had neither means to taste the bitterness nor livers
effective enough to detoxify the substances. They died of massive overdoses.

3. Disasters: A large comet or asteroid struck the earth some 65 million years ago, lofting a cloud of dust into the sky and blocking sunlight, thereby suppressing photosynthesis and so drastically lowering world temperatures that dinosaurs and hosts of other creatures
became extinct.

Before analyzing these three tantalizing statements, we must establish a basic ground rule often violated in proposals for the dinosaurs’ demise. There is no separate problem of the extinction of the dinosaurs. Too often we divorce specific events from their wider contexts and systems of cause and effect. The fundamental fact of dinosaur extinction is its synchrony with the demise of so many other groups across a wide range of habitats, from terrestrial to marine.

The history of life has been punctuated by brief episodes of mass extinction. A recent analysis by University of Chicago paleontologists Jack Sepkoski and Dave Raup, based on the best and most exhaustive tabulation of data ever assembled, shows clearly that five episodes of mass dying stand well above the “background” extinctions of normal times (when we consider all mass extinctions, large and small, they seem to fall in a regular 26-million-year cycle...). The Cretaceous debacle, occurring 65 million years ago and separating the Mesozoic and Cenozoic eras of our geological time scale, ranks prominently among the five. Nearly all the marine plankton (single-celled floating creatures) died with geological suddenness; among marine invertebrates, nearly 15 percent of all families perished, including many previously dominant groups, especially the ammonites (relatives of squids in coiled shells). On land, the dinosaurs disappeared after more than 100 million years of unchallenged domination.

In this context, speculations limited to dinosaurs alone ignore the larger phenomenon. We need a coordinated explanation for a system of events that includes the extinction of dinosaurs as one component. Thus it makes little sense, though it may fuel our desire to view mammals as inevitable inheritors of the earth, to guess that dinosaurs died because small mammals ate their eggs (a perennial favorite among untestable speculations). It seems most unlikely that some disaster peculiar to dinosaurs befell these massive beasts—and that the debacle happened to strike just when one of history’s five great dyings had enveloped the earth for completely different reasons.

The testicular theory, an old favorite from the 1940s, had its root in an interesting and thoroughly respectable study of temperature tolerances in the American alligator, published in the staid Bulletin of the American Museum of Natural History on 1946 by three experts on living and fossil reptiles—E.H. Colbert, my own first teacher in paleontology; R.B. Cowles; and C.M. Bogert.

The first sentence of their summary reveals a purpose beyond alligators: “This report describes an attempt to infer the reactions of extinct reptiles, especially the dinosaurs, to high temperatures as based upon reactions observed in the modern alligator.” They studied, by rectal thermometry, the body temperatures of alligators under changing conditions of heating and cooling. (Well let’s face it, you wouldn’t want to try sticking a thermometer under a ‘gator’s tongue.) The predictions under test go way back to an old theory first stated by Galileo in the 1630s—the unequal scaling of surfaces and volumes. As an animal, or any object, grows (provided its shape doesn’t change), surface areas must increase more slowly than volumes— since surfaces get larger as length squared, while volumes increase much more rapidly, as length cubed. Therefore, small animal have high ratios of surface to volume, while large animals cover themselves with relatively little surface.

Among cold-blooded animals lacking any physiological mechanism for keeping their temperatures constant, small creatures have a hell of a time keeping warm—because they lose so much heat through their relatively large surfaces. On the other hand, large animals, with their relatively small surfaces, may lose heat so slowly that, once warm, they may maintain effectively constant temperatures against ordinary fluctuations of climate. In fact, the resolution of the “hot- blooded dinosaur” controversy that burned so brightly a few years back may simply be that, while large dinosaurs possessed no physiological mechanism for constant temperature, and were not therefore warm-blooded in the technical sense, their large size and relatively small surface area kept them warm.

Colbert, Cowles, and Bogert compared the warming rates of small and large alligators. As predicted, the small fellows heated up (and cooled down) more quickly. When exposed to a warm sun, a tiny 50-gram (1.76 ounce) alligator heated up one degree Celsius every minute and a half, while a large alligator, 260 times bigger at 13,000 grams (28.7 pounds), took seven and a half minutes to gain a degree. Extrapolating up to an adult 10-ton dinosaur, they concluded that a one-degree rise in body temperature would take eighty-six hours. If large animals absorb heat so slowly (through their relatively small surfaces), they will also be able to shed any excess heat gained when temperatures rise above a favorable level.

The authors then guessed that large dinosaurs lived at or near their optimum temperatures. Cowles suggested that a rise in global temperatures just before the Cretaceous extinction caused the dinosaurs to heat up beyond their optimal tolerance—and, being so large, they couldn’t shed the unwanted heat. (In a most unusual statement within a scientific paper, Colbert and Bogert then explicitly disavowed this speculative extension of their empirical work on alligators.) Cowles conceded that this excess heat probably wasn’t enough to kill or even to enervate the great beasts, but since testes often function within a narrow range of temperature, he proposed that this global rise might have sterilized all the males, causing extinction by natural contraception.
The overdose theory has recently been supported by UCLA psychiatrist Ronald K. Siegel. Siegel has gathered, he claims, more than 2,000 records of animals who, when given access, administer various drugs to themselves—from a mere swig of alcohol to massive doses of the big H. Elephants will swill the equivalent of twenty beers at a time, but do not like alcohol in concentrations greater than 7 percent. In a silly bit of anthropocentric speculation, Siegel states that “elephants drink, perhaps, to forget...the anxiety produced by shrinking rangeland and the competition for food.”

Since fertile imaginations can apply almost any hot idea to the extinction of dinosaurs, Siegel found a way. Flowering plants did not evolve until late in the dinosaurs’ reign. These plants also produced an array of aromatic, amino-acid-based alkaloids—the major group of psychoactive agents. Most mammals are “smart” enough to avoid these potential poisons. The alkaloids simply don’t taste good (they are bitter); in any case, we mammals have livers happily supplied with the capacity to detoxify them. But, Siegel speculates, perhaps dinosaurs could neither taste the bitterness nor detoxify the substances once ingested. He recently told members of the American Psychological Association: “I’m not suggesting that all dinosaurs OD’d on plant drugs, but it certainly was a factor.” He also argued that death by overdose may help explain why so many dinosaur fossils are found in contorted positions. (Do not go gentle into that good night.)

Extraterrestrial catastrophes have long pedigrees in the popular literature of extinction, but the subject exploded again in 1979, after a long lull, when the father-son, physicist-geologist team of Luis and Walter Alvarez proposed that an asteroid, some 10 km in diameter, struck the earth 65 million years ago.
The force of such a collision would be immense, greater by far than the megatonnage of all the world’s nuclear weapons. In trying to reconstruct a scenario that would explain the simultaneous dying of dinosaurs on land and so many creatures in the sea, the Alvarezes proposed that a gigantic dust cloud, generated by particles blown aloft in the impact, would so darken the earth that photosynthesis would cease and temperatures drop precipitously. (Rage, rage against the dying of the light.) The single-celled photosynthetic oceanic plankton, with life cycles measured in weeks, would perish outright, but land plants might survive through the dormancy of their seeds (land plants were not much affected by the Cretaceous extinction, and any adequate theory must account for the curious pattern of differential survival). Dinosaurs would die by starvation and freezing; small, warm-blooded mammals, with more modest requirements for food and better regulation of body temperature, would squeak through. “Let the bastards freeze in the dark,” as bumper stickers of our chauvinistic neighbors in sunbelt states proclaimed several years ago during the Northeast’s winter oil crisis.

All three theories, testicular malfunction, psychoactive overdosing, and asteroidal zapping, grab our attention mightily. As pure phenomenology, they rank about equally high on the hit parade of primal fascination. Yet one represents expansive science, the others restrictive and untestable speculation. The proper criterion lies in evidence and methodology; we must probe behind the superficial fascination of particular claims.

How could we possible decide whether the hypothesis of testicular frying is right or wrong? We would have to know things that the fossil record cannot provide. What temperatures were optimal for dinosaurs? Could they avoid the absorption of excess heat by staying in the shade, or in caves? At what temperatures did their testicles cease to function? Were late Cretaceous climates ever warm enough to drive the internal temperatures of dinosaurs close to this ceiling? Testicles simply don’t fossilize, and how could we infer their temperature tolerances even if they did? In short, Cowles’s hypothesis is only an intriguing speculation leading nowhere. The most damning statement against it appeared right at the conclusion of Colbert, Cowles, and Bogert’s paper, when they admitted: “It is difficult to advance any definite arguments against this hypothesis.” My statement may seem paradoxical—isn’t a hypothesis really good if you can’t devise any arguments against it? Quite the contrary. It is untestable and unusable.

Siegel’s overdosing has even less going for it. At least Cowles extrapolated his conclusion from some good data on alligators. And he didn’t completely violate the primary guideline of siting dinosaur extinction in the context of a general mass dying—for rise in temperature could be the root cause of a general catastrophe, zapping dinosaurs by testicular malfunction and different groups for other reasons. But Siegel’s speculation cannot touch the extinction of ammonites or oceanic plankton (diatoms make their own food with good sweet sunlight; they don’t OD on the chemicals of terrestrial plants). It is simply a gratuitous, attention-grabbing guess. It cannot be tested, for how can we know what dinosaurs tasted and what their livers could do? Livers don’t fossilize any better than testicles.

The hypothesis doesn’t even make any sense in its own context. Angiosperms were in full flower ten million years before dinosaurs went the way of all flesh. Why did it take so long? As for the pains of a chemical death recorded in contortions of fossils, I regret to say (or rather I’m pleased to note for the dinosaurs’ sake) that Siegel’s knowledge of geology must be a bit deficient; muscles contract after death and geological strata rise and fall with motions of the earth’s crust after burial—more than enough reason to distort a fossil’s pristine appearance.

The impact story, on the other hand, has a sound basis in evidence. It can be tested, extended, refined and, if wrong, disproved. The Alvarezes did not just construct an arresting guess for public consumption. They proposed their hypothesis after laborious geochemical studies with Frank Asaro and Helen Michel had revealed a massive increase of iridium in rocks deposited right at the time of the extinction. Iridium, a rare metal of the platinum group, is virtually absent from indigenous rocks of the earth’s crust; most of our iridium arrives on extraterrestrial objects that strike the earth.
The Alvarez hypothesis bore immediate fruit. Based originally on evidence from two European localities, it led geochemists throughout the world to examine other sediments of the same age. They found abnormally high amounts of iridium everywhere—from continental rocks of the western United States to deep sea cores from the South Atlantic.

Cowles proposed his testicular hypothesis in the mid-1940s. Where has it gone since then? Absolutely nowhere, because scientists can do nothing with it. The hypothesis must stand as a curious appendage to a solid study of alligators. Siegel’s overdose scenario will also win a few press notices and fade into oblivion. The Alvarezes’ asteroid falls into a different category altogether, and much of the popular commentary has missed this essential distinction by focusing on the impact and its attendant results, and forgetting what really matters to a scientist—the iridium. If you talk just about asteroids, dust and darkness, you tell stories no better and no more entertaining than fried testicles or terminal trips. It is the iridium—the source of testable evidence—that counts and forges the crucial distinction between speculation and science.

The proof, to twist a phrase, lies in the doing. Cowles’s hypothesis has generated nothing in thirty-five years. Since its proposal in 1979, the Alvarez hypothesis has spawned hundreds of studies, a major conference, and attendant publications. Geologists are fired up. They are looking for iridium at all other extinction boundaries. Every week exposes a new wrinkle in the scientific press. Further evidence that the Cretaceous iridium represents extraterrestrial impact and not indigenous volcanism continues to accumulate. As I revise this essay in November 1984, new data include chemical “signatures” of other isotopes indicating unearthly provenance, glass spherules of a size and sort produced by impact and not by volcanic eruptions, and high-pressure varieties of silica formed (so far as we know) only under the tremendous shock of impact.

My point is simply this: Whatever the eventual outcome (I suspect it will be positive), the Alvarez hypothesis is exciting, fruitful science because it generates tests, provides us with things to do, and expands outward. We are having fun, battling back and forth, moving toward a resolution, and extending the hypothesis beyond its original scope (see “The Cosmic Dance of Siva” for some truly wondrous extensions).
As just one example of the unexpected, distant cross-fertilization that good science engenders, the Alvarez hypothesis made a major contribution to a theme that has riveted public attention in the past few months—so-called nuclear winter. In a speech delivered in April 1982, Luis Alvarez calculated the energy that a ten-kilometer asteroid would release on impact. He compared such an explosion with a full nuclear exchange and implied that all-out nuclear war might unleash similar consequences.

The theme of impact leading to massive dust clouds and falling temperatures formed an important input to the decision of Carl Sagan and a group of colleagues to model the climatic consequences of nuclear holocaust. Full nuclear exchange would probably generate the same kind of dust cloud and darkening that may have wiped out the dinosaurs. Temperatures would drop precipitously and agriculture might become impossible. Avoidance of nuclear war is fundamentally an ethical and political imperative, but we must know the factual consequences to make firm judgments. I am heartened by a final link across disciplines and deep concerns— another criterion, by the way, of science at its best: A recognition of the very phenomenon that made our evolution possible by exterminating the previously dominant dinosaurs and clearing a way for the evolution of large mammals, including us, might actually help to save us from joining those magnificent beasts in contorted poses among the strata of the earth.

From The Flamingo’s Smile (1985, W. W. Norton and Company) Originally published in Discover Magazine, Time Inc., 1984


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ORIGINAL: WickedsDesire

You inbreeds still teach that in your schools? lack of genetic diversity I suppose.

38% really guffaws

i cant see my screen i have a cat sitting in front of it

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You are just like them in the fact you keep confusing occurred with could have occurred and now you bring up "how it happened" not how it could of happened.

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ORIGINAL: Milesnmiles
Okay, since you keep insisting that I don't understand science and you seem to like to define what science is for us, let's look at what you have to say.
Which is closer to agreeing with what you say science is;
My statement, from someone who "doesn't understand science"; that at best science "shows" that evolution could be true or your statement; "that evolution happened is pretty well established".

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ORIGINAL: Musicmystery
Sure. But "at best" here means that the evidence indicates the hypothesis holds up consistently. That's pretty solid. Unless you've got a better supported alternative.

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ORIGINAL: Milesnmiles
Which one seems to be a "belief" in something

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ORIGINAL: Musicmystery
No, that's silly. "All the evidence suggests this is true" certainly rises above a mere belief. In fact, when I believe something, and I find the evidence shows something else, I recognize that my belief was false.

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ORIGINAL: Milesnmiles
and seems to show they have stopped assuming "we have more to learn"?

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ORIGINAL: Musicmystery
No. That we could always potentially undercover new information doesn't mean we haven't learned so far, or that we think we now know everything.

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ORIGINAL: Musicmystery
In fact, studies of evolution continue to the present day.

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ORIGINAL: Musicmystery

I see we've reached the personal insult portion of the "discussion."

I'll consider that my cue that you've nothing left to say and need a way to huff off into the sunset.

Enjoy. We're done here.

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ORIGINAL: vincentML

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You are just like them in the fact you keep confusing occurred with could have occurred and now you bring up "how it happened" not how it could of happened.

In a way, you are correct. Darwin did not invent evolution. He suggested a method for how it may have, must have occurred. MM alluded to this so let me pin it down for you. Fifty years or so before Darwin wrote his books on the evolution of species several geologists constructed maps of the earth's rock formations and found they showed catastrophic occurrences. . . . great changes in the strata of the rock given to upheavals by volcanoes and whatever. Studying these relatively abrupt changes and the fossil record revealed by them geologists discovered that at times entire species were wiped out and new species appeared after the catastrophe.

Later, a British geologist, Charles Lyell, rebelled against the orthodoxy of catastrophism and claimed that changes in the earth took places gradually over long periods of time.

Darwin was confronted with the observation that new species appeared. He wondered how that happened. He studied finches in the Galapagos Islands and noted that the birds filled a niche according to their beak structure. They lived in the rocks where their beaks made catching and eating specific insects easier.

How did that happen? Did God visit the earth after each catastrophe (my thoughts, not Charlie's) and make new species? Did God make a bird with a different beak shape for each location in the Galapagos rocks? No evidence for that. To explain what he and others saw Darwin suggested that species were formed by adaptation to the new environment. Only they survived.

BUT WAIT!!!!! That does not mean the creature changed to fit in. NO! Fucking NO! Pay attention now cuz this is why your doctor admonishes you to use all your antibiotics. There were a number of individuals already present in the environment and they had a variety of genes and characteristics. When the environment changed, either gradually or catastrophically, some members of the population were better suited for the new environment. They survived, not their cousins.

population with variants > environment change > survival of some variants.

For example, if there are fish with lungs amongst a population where some only have gills.. If their pond dries up the whole gang may try to flip over to the next pond but only those with lungs will get across the dry land and make it to the next pond. The others will be road kill.

Do we have evidence to support this theory of selection? Tons of it. First among live stock breeders who can alter the herd. Or among wolves who hung around primitive camps and became domesticated into dogs and were then subject to selective breeding. And certainly in bacteria whose populations contain variants that are resistant to antibiotics. So if man can breed dogs selectively and nature can breed bacteria selectively there is no reason to think nature cannot breed other species selectively by having variants who can survive environmental changes. There are examples of polyploidy plants in the same field with their precursors. Polyploidy is change by doubling or tripling the chromosomes and genes. Humans have tissues that are differentiated due to polyploidy changes.

Does that help? Fuck it. Too bad then.

I do hope that helps a bit.

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Help? It is the same simplistic mumbo jumbo that Evolutionists have been trying pass off as evidence that evolution is a fact for years.

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ORIGINAL: Milesnmiles

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ORIGINAL: Musicmystery

I see we've reached the personal insult portion of the "discussion."

I'll consider that my cue that you've nothing left to say and need a way to huff off into the sunset.

Enjoy. We're done here.

Yes, you sure have.

Feel free to come back if you actually think of something to say.

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ORIGINAL: Musicmystery

Whichever his answer, then ask him how that's not simplistic mumbo jumbo.

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ORIGINAL: Musicmystery

Whichever his answer, then ask him how that's not simplistic mumbo jumbo.

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ORIGINAL: tweakabelle
You argument on this thread appears to be this:
Evolution is not a "fact' nor is it "proven".

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ORIGINAL: tweakabelle
Therefore science is wrong (as you assert that evolutionists claim evolution to be a 'fact')

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ORIGINAL: tweakabelle
And anyway, as it is neither a 'fact' nor proven to be true, it is either (a) unworthy of further consideration or (b) no better or worse, or no more or less deserving of consideration than any competing explanation eg. Genesis) or possibly both (a) and (b).

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ORIGINAL: tweakabelle
Fair enough. No one is disputing that evolutionary theories are not facts or claiming they have been proven beyond any reasonable doubt. Amazingly, everyone seems to agree that this is not the case. Science has never produced a "fact" in its history nor is it capable of doing so. Ever.

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ORIGINAL: tweakabelle
However it doesn't follow from the above that science is "wrong" or that evolutionary theories are undeserving of further consideration.

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ORIGINAL: tweakabelle
Science, conducted properly according to its own rules and principles is never 'right' or 'wrong'. Properly followed, science is incapable of being 'right' or 'wrong'. "Right' and 'wrong' are value judgements which have no place in properly conducted science - they are the property of belief and/or moral systems. Science is a methodology, not a belief system. The highest possible achievement of science is to produce the best available explanation that accounts for the data in a non-trivial fashion.

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ORIGINAL: tweakabelle
The primary merit of evolutionary theories is that they are the best available explanations of the data. As such they are absolutely worthy of further consideration until a better explanatory model is produced. As such they are far more deserving of consideration than any other explanation and will remain so until a better explanation comes along.

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ORIGINAL: tweakabelle
'Creationist' explanations don't even come into this ballpark. (Alternatively if you want to insist they do, then so do all the other myths and fairy tales that claim to account for the universe's existence, and humans' place in that universe, all of which possess exactly the same legitimacy as 'creationism'.) ID perspectives which claim to be scientific simply aren't scientific. They are creationist mumbo jumbo under another name, fraudulently misrepresenting themselves to be scientific.