Advertisement
Share

Beastly Debate : Inquiring Minds Fight, Fume Over What Happened to Dinosaurs

One fine Cretaceous morning, about 65 million years ago, the dinosaurs woke up to see this . . . thing. A dot in the sky that quickly grew into a vast black rock hurtling toward them from the depths of space--faster, bigger, until . . . splat !

The dinosaurs who were not squished that horrible day were soon shivering to death in a nuclear winter.

That’s one theory. Here’s another:

The giants were munching on grass and treetops one sunny day when their tiny brains perceived a rumble that grew into a deafening roar. Far off, volcanoes ripped out the guts of the Indian subcontinent and shot a plume of molten innards into the sky so thick that the carbon dioxide got trapped, and the dinosaurs wilted into extinction in the heated, airless vacuum below.

Or: Nemesis, the Death Star, our sun’s devilish invisible sister, sucked in the Oort cloud of comets and caused them to rain down upon the earth, with no consideration for its Gargantuan inhabitants.

Advertisement

Or: As speculated by a recent supermarket tabloid, “Big Game Hunters From Mars Gunned Down Our Dinosaurs,” hauled their burly carcasses home to the Red Planet, where brontosaurus fajitas and triceratops sirloin are being served up to this very day.

Debate Is Wide-Open

In other words, nobody knows what happened to the dinosaurs. The debate is wide-open. New theories are being reported so often you would think the fate of dinosaurs was a breaking story.

Just the other day, a pair of Caltech scientists called a press conference and fired a 50-foot gun to help dramatize their notion that a 10-mile-thick comet slammed into a limestone deposit somewhere on Earth and that resulting clouds of carbon dioxide heated the atmosphere and cooked the dinosaurs like so many lumps of diced fowl in a crock pot.

Whether we ever learn the truth, the search itself has taken on its own importance, and created its own drama--with some very serious players. And that brings us to another sunny day, in the Quaternary Period some 65 million years later. March 11, 1988, to be precise.

A gaggle of scientists are blinking in the sun of Vacation Village--a manicured paradise of cabanas now collectively called the Princess Hotel--waiting to file into a dark hall where the shuddering horrors of Mother Earth’s Breech Birth and Difficult Childhood are about to be relived.

Battle of the Boundary

This is the “Battle of the KT Boundary,” and it’s serious business. Scientific reputations, grants-in-aid and careers all hang in the balance. Why did the dinosaurs die? Inquiring minds think they know.

The KT Boundary marks the end of the Cretaceous Period--during which the dinosaurs roamed--and the beginning of the current Tertiary Period, about 65 million years ago.

Most of the books resting among the inflatable plastic dinosaurs at shops like The Nature Company, a rocks-for-yuppies emporium at Horton Plaza, explain that while the KT Boundary was bad news for the dinosaurs, it was a break for mankind. That’s where we brainy bipeds got our chance to become the pre-eminent inhabitants of Earth.

There is some irony in the fact that the KT Boundary battle was being fought on the last day of the Chapman Conference on the Gaia Hypothesis, an occasion that was intended to promote congenial discussions on the theme of the Earth as a living organism attempting to regulate itself.

Crash vs. Blast

But inside the Mission Bay Conference Room, the disharmony crackled. The dinosaur battle lines were drawn. On one side were three “Impactors"--proponents of the theory that meteors did the dinosaurs in. On the other side was a lone “Volcanite,” espousing the notion that volcanic eruptions did the job.

The Volcanite--University of Colorado physicist Alan Rice--was outmanned, but committed, as he nervously fingered the carrousel of slides that he hoped would convince 158 of his academic peers.

Ask Rice a couple of questions about the “differences of opinion” between the dinosaur experts, and a long and tortuous story emerges, a story of intrigue, professional harassment and academic Realpolitik. Rice points to a golden-haired gentleman hovering over his own box of slides five rows ahead of him. It is Walter Alvarez, son of Luis Alvarez, the man who first proposed the comet-collision theory 17 years ago.

“It’s only because Walter Alvarez and his father once told me, in no uncertain terms, to sit down that I’m here, that I got involved,” Rice said.

Weren’t Being Polite

The Alvarezes hadn’t invited Rice to take a load off his feet that day. They told him not to make a fuss. The incident, as Rice tells it, occurred during a lecture that Walter and Luis Alvarez were giving on the meteor-impact theory at the University of Colorado in 1985.

Rice had been studying pressures in volcanoes at the time and he wanted to question the Alvarezes’ assumption that the dinosaurs had died out because of a comet’s collision with Earth. Rice said that when the lecture ended, he stood during a question-and-answer session and raised his issue.

“They didn’t give me an answer,” Rice said. “They just said, ‘Please sit down. We’re not going to confuse the audience with technical issues.’ So I said, ‘I’ll sit down, but I’ve left the question standing.’ ”

The question has been standing between Rice and the Alvarezes ever since.

What has happened in the meantime has been partly scientific competition, partly Dr. Strangelove excesses, partly darkly rumored moves of professional coercion. According to Rice, those who would challenge Alvarez’s theory of dinosaur extinction faced proessional extinction themselves.

Luis Alvarez is a formidable person for any academic to take on. He is a Nobel laureate. He won the prize in physics in 1968 for discoveries in the field of nuclear particles. He played an important role in the development of the atomic bomb, and actually flew on the raid that leveled Hiroshima. He was even brought in as part of the scientific team analyzing physical evidence involved with John Kennedy’s assassination.

But in the past decade, his name has been most often linked with the impact-collision theory of dinosaur extinction. His geologist son, Walter, and associates Frank Asaro and Helen Michel have been gathering evidence to support the theory for years.

Renegade Paleontologist

Opposition to the cataclysmic-event idea began in 1978 with a renegade paleontologist from Virginia Polytechnic Institute named Dewey McLean. McLean also knew a lot about biology. He had noticed, for instance, how European cows exported to hot Latin American countries reproduced poorly. He suggested that the dinosaurs had suffered the same fate.

McLean said the dinosaurs lost their reproductive abilities because of the heat, and that it got hot because of the amount of carbon dioxide built up from the death of carbon dioxide-munching plants and algae. They were living in a giant greenhouse.

Two years later, McLean accounted for the disaster with the argument that the Deccan Traps, a huge orchestra of volcanoes in India at about the time of the KT Boundary, poured out the carbon dioxide and wiped out much of life on Earth.

There was no need to speculate on massive meteor collisions, he said. Who needed them?

New Collision Course

McLean’s theory, however, charted a new collision course, between himself and the powerful proponents of Luis Alvarez. McLean claims he and others were subjected to heavy political pressures inside academia, that his tenure at Virginia Polytechnic had actually been jeopardized by his opposition to the pro-meteor group.

“Luis calls me a weak sister who got knocked out of the game years ago,” McLean said in a later telephone interview. “That’s wishful thinking on his part . . . What was offensive was not the idea of an asteroid-impact catastrophe, but the hard attitude of the people who did not understand the KT record, getting rough with people who had studied it for a long time . . . calling them fools. When a Nobel laureate publicly calls you a fool, that doesn’t help your career . . . Right beneath the glamour of dinosaurs and extinctions there are dark worlds.”

Both Rice and McLean say that attaching yourself to successful research is an important factor in assuring tenure and promotion--and grants for pet projects.

“The Alvarezes are powerful people,” said McLean. “But Luis doesn’t have a background in biology, of the organisms whose fossils you have to examine to confirm any theory . . . on such a huge event. If they had been nice guys and come into paleontology, we would have welcomed them. It could have been marvelous fun to have them say ‘Hey guys, can we come into paleontology and try things?’

“But, in fact, they . . . wrote their paper in 1980, and almost immediately Luis Alvarez said there was no longer any debate . . . and paleontologists weren’t really very good scientists. They were more like stamp collectors. That’s what he called us. The issue was settled.”

Gloomy Predictions

Listening to the talks during the Gaia conference--named for the Greek Earth goddess--you wouldn’t have known it wasn’t the most affable of egghead gatherings. In the nicest possible way, as they casually clicked through their slides of fossils and digs and graphs, the Impactors and the lone Volcanist debated whether “shocked minerals” actually came from asteroids. Whether an element called iridium (the kind you find in your platinum ring) comes only from comets. Whether comets could have agitated the molten caldron around the core of Earth and set off a rash of monstrous volcanoes.

Walter Alvarez was the first of the principle theorists to speak. His father was said to be seriously ill, and did not attend the conference.

“There are craters everywhere, from Arizona to Siberia . . . evidence of comets,” Walter Alvarez said. “When we started this story, there was a storm of protests. It scandalized geologists . . .”

Alvarez darkly referred to an approaching comet 40 kilometers in diameter that, should it touch down on Earth, would sterilize all life on the planet.

E. G. Kauffman, another Impactor, followed Alvarez with the bleak report that “99.95% of all life experiments have failed” and that “mass extinctions have no consistency with high or low volcanism, so we must look to outer space.”

Kauffman suggested that mass extinctions might be a useful way of cleansing the Earth of one biota--the animal and plant life of the planet--in order to make way for a new one. Thus, the dinosaurs and other Cretaceous beings were somehow cleansed from our world, making way for us. Kauffman then cited evidence of a traumatic event in the Caribbean. Perhaps the Impactors’ Big Comet had hit the sea and caused massive, lethal tidal waves.

A Lone Dissenter

By the time Rice rose to speak, five minutes had been drained from his time by the previous speakers; along with the time went heaps of good will.

“I appear to be the only one who sees the extraterrestrial explanation for the KT Boundary as a case of the emperor’s new clothes,” Rice said.

He went on to quote Chicago statisticians who have compared the probability of regular comet showers every 30 million years to the odds against cyclical rains of polystyrene cups.

The Impactor-prone audience was not amused.

When Rice was told abruptly that his time was up, he left the stage, then sarcastically thanked Kauffman for pinching his time.

The next speaker, Michael Rampino of New York University, questioned the reliability of Rice’s statisticians. Rampino believes that periodic meteor showers resulted from the planet’s wandering near the Oort cloud, a cluster of comets beyond Pluto, and said it’s possible the dinosaurs died of sunburn.

Rampino said zero albedo --a condition of absolutely clear blue skies resulting from the death of rainmaking plants and algae--might have blistered the creatures to an eternal fare-thee-well, and he hinted that people like Alan Rice are using “bad data.”

Despite the extended post-presentation debate, Rice never got a chance to raise the fact that such dinosaurs as the triceratops, with its massive fleshy scales serving as “heat shields,” survived a million years longer than others, a piece of evidence that he says contradicts the notion of a comet-caused cataclysm.

Learning From the Past

For observers of the scientific debate over the fate of dinosaurs, nothing is certain except the passion with which the various advocates hold their views.

“Yes, tempers have flared,” Walter Alvarez said of the 10-year debate. “People have said things they later regretted, but, by and large, decency and respect have been the rule. I’m portrayed as the heavy opposition. But I get on with most of those I disagree with.”

He said the conference helped him realize the need for a multidisciplinary approach to such large subjects. On that point, at least, he and Rice and McLean agree.

But, after all this, does anybody really care ? Outside the arcane power struggles of the world of science, does it matter whether the dinosaurs were taken out by comets, meteors, volcanoes or tidal waves?

“The earth is warming. We’re facing a greenhouse future,” said one of the scientists, indignant that the question was asked. “We have to find out how dangerous excess amounts of carbon dioxide are. We still have a chance to do something about it. And what if the warming effect changes the breeding habits of our cattle, the livestock we eat, as it may have the dinosaurs? It could radically affect our food supply. The KT extinctions aren’t just refighting yesterday’s football match. We have to learn from our past to arm ourselves for the future.”

As the crowd thinned out after the Gaia dinosaur session, the scientists were buzzing with the day’s input. A geographer, Lee Klinger, said he doesn’t care who wins this debate, because they both agree that whatever happened to the flora and fauna before the KT Boundary, it produced acid rain, which is good for bogs. Klinger is a bog man, with detailed theories on the origin of bogs and bog life.

“Relevant?” huffed another scientist. “We’re facing another greenhouse today. If volcanoes did it back at KT, fossil fuels are the volcanoes of today. Man-made! We can do something about that. Of course it’s relevant.”

It was a brain-bruising afternoon. How could the world look the same again?

Yet, in the glare of the world outside, the Quaternary Period looked surprisingly peaceful. There was a zero albedo sky. The sun was setting in its normal place. There was no sign of its sister, the Death Star Nemesis, or even a chunk of asteroid rock hurtling down toward the Mission Bay Conference Hall. Not a single big-game hunter from Mars in sight.

But, if your highly evolved brain has room for one more theory on this subject, there were some interesting and relevant creatures in the sky. Circling overhead, unaware of their heritage, were a pair of tiny . . . dinosaurs. You would call them pigeons.

“Those birds are direct descendants of certain dinosaurs that adapted their forearms to a slightly different use. Dinosaurs are not extinct!” said Robert M. Sullivan, a paleontology research associate for the Natural History Museum of Los Angeles County and the San Diego Natural History Museum.

Disaster Denied

Sullivan, not one to mince words or mulch theories, said the whole KT Boundary debate is nonsense.

“There was no disaster,” he said. “Dinosaurs were walking and flying before, during and after (the KT Boundary). This is people trying to tie up neat ends when there aren’t any--volcano buffs and comet-impact people alike. How many dinosaur species are we talking about going extinct? Twelve? Thirteen? That took one asteroid?

“We have 1,000 species going extinct every year in our time. At (one asteroid per 13 species), you’d need an annual 83.3 (asteroids) smashing into us to keep that rate of extinction up. Too many (scientists) read stratographic records like fundamentalists read the Bible--literally. And they haven’t appreciated how wide the dinosaur family is.”


Advertisement