Farmers in Riodeva, Spain, have found the remains of the largest dinosaur in Europe. The bones include an upper limb as big as a 6-foot-tall person. It is Spain’s greatest fossil find.

The remains are of a huge herbivore, which measured 114-feet long and weighed an estimated 40 to 50 tons (the same as six or seven elephants). It could represent a new species. What’s interesting is that other bones were found at the site, including including teeth from carnivores that may have feasted on its flesh.

The dinosaur probably roamed the region up to 130 million years ago when this region was a lush tropical landscape laced with rivers and streams.

It has long been known that multicellular life grew rapidly some 540 million years ago — during the time period known as the Cambrian explosion. Now Jun-Yuan Chen of the Nanjing Institute of Geology and Paleontology and an international team of researchers believe they have have found evidence for the beginnings of this revolution.

While working in southwest China, the researchers discovered 10 fossils some 600 million years old! They are tiny life forms, measuring just 200 micrometers across. What’s important is that they are oval in shape, making them the earliest evidence of animals with such noncircular structure. The researchers called them Vernanimalcula guizhouena, or "small spring animal." Small as they are, the animals have a number of organs, including including mouths, guts, possible sense organs, and body cavities.

Don’t worry, some dinosaurs had them too. That’s right, scientists have discovered a new species of dinosaur that had the same facial "problem." The 95-million-year-old dinosaur, named Rugops primus, ("first wrinkle face") was related to other wrinkled monsters that roamed the earth some 135 million years ago.

Famous dinosaur hunter Paul Sereno (University of Chicago) and his colleagues discovered Rugops primus. The 30-foot-long creature had a short, round snout, small teeth and a tough covering of scales. The researchers also recovered the 135-million-year-old spine of another dinosaur, Spinostropheus gautieri, which is an ancient relative of Rugops and other abelisaurids.

What’s interesting is that these related species lived in Africa, South America, and India! Hmm. If you’re any good at geography you’ll realize that great oceans separate these land masses. Yes, by studying and dating these wrinkled critters, scientists can learn more about how and when great land masses on Earth — once joined — began to split and drift apart.

It stood nine meters tall, and its blade-like teeth were perfectly suited for ripping into flesh. It fed upon the remains of other dinosaurs, including gigantic long-necked sauropods called titanosaurs. But it also had an appetite for others of its kind. Yes, Majungatholus atopus was a ferocious dinosaur. It was a carnivore. . . and a cannibal!

Majungatholus atopus feeds on its prey (Courtesy Greg Helgeson, Macalester College, St. Paul, Minn.)

Raymond Rogers (Macalester College in St. Paul, MN) and his colleagues arrived at this conclusion after studying 21 fossilized bones of Majungatholus, which roamed the plains of Madagascar between 65 and 70 million years ago. The remains, which came from two Majungatholus individuals, have distinct markings that match the size and spacing of teeth in another Majungatholus skull. "We can definitely rule out all of the other carnivores known to have been on the scene," Rogers explains, leaving only Majungatholus to feed on Majungatholus.

This discovery has now whet the appetite of other dinosaur diggers who had suspected another dinosaur — Coelophysis bauri — of being a cannibal. Now that case needs to be reexamined.

As for Majungatholus, the evidence shows that it regularly dined upon members of its own species. "We have examined literally thousands of dinosaur bones from sites around the world, and we’ve never seen fossil material quite like this," Rogers says.

Despite human revulsion at cannibalism, it is not surprising to conceive of cannibalistic dinosaurs. From insects to lions, cannibalism is a common feeding strategy in the animal kingdom today.

The fossilized Footprints of three small human-like creatures — known locally in Italy as the "devils’ trails" — have been uncovered on the Roccamonfina volcano in southern Italy. The prints were made while the hominids were climbing down the side of the mountain about 385,000 to 325,000 years ago. They are the oldest set of human footprints to be discovered.

Paolo Mietto (University of Padua), the lead investigator of the team that found the prints, believes the primitive humans stood a mere 1.5 meters tall, walked on two legs, and used their hands to steady themselves during the steep descent.

Three tracks with prints in the fossilized volcanic ash were found. The tracks, designated A, B and C, descend a slope that in places is almost vertical.

Trail A consist of 27 footprints, which at one point follow a Z-shaped path presumably made to negotiate the slope more easily.

Trackway B is composed of 19 footprints crossing the slope in a single straight line and curving roughly 45 degrees to the right. There is evidence of slipping — an occasional handprint can be seen on the slope beside the track.

In contrast trackway C follows a straight line with 10 regular footprints made over a smaller incline.

After studying the prints, Mietto believes there are enough similarities in the gait of these creatures to support the idea that they are indeed human.

Leaping Lizards! It’s a pouncing predator . . . with feathers! Here we go again. New evidence in the bird-dino debate is turning our thinking upside "down." There have been two large camps of thinking about the origins of bird flight. Some scientists say that bird flight began after small reptiles started climbing trees for insects and other crawly things. Over time they gradually developed wings that helped them glide down back to the ground. The other camp of scientists says "No way! Fast-running dinosaurs developed feathers for insulation, then used them to take ever greater leaps into the air to snatch their flying insects."

Now, are you ready for this? The new evidence says, "Ha! Both camps are wrong!" Instead, the fossil record shows that dinosaurs developed wings to jump onto prey from ledges and rocks. And that includes our feathered friend the famous Archaeopteryx. Scientists are now calling these pouncing protobird "proavis." And the fancy feathers they displayed were used to control and balance the creature’s body during a feet-first, predatory leap. In time, the pounce became a swoop, which finally led to true flapping flight. So now we have ambushing aviators. Cool. Of course, some time in the near future, those scientists mentioned in the first paragraph will be sharpening their verbal talons for a counter attack. Until then, this new theory seems to have have taken one small step forward for science, and one giant "leap" for birdkind.

Scientists from the Field Museum in Chicago, Illinois, have unearthed what appear to be the oldest dinosaur fossils ever found. The fossilized remains – jaw bones from two new plant-eating dinosaurs – date from the middle to late Triassic Period, 225 to 230 million years ago.

The fossils are located on Madagascar, an island in the Indian Ocean. Field Museum scientists John J. Flynn and his colleagues first learned of them in 1996, after a young villager, named Mena, said that he knew of the whereabouts of some bones. Flynn said they followed Mena to a hill of red dirt that turned out to be a treasure trove of ancient fossils. The scientists returned to Madagascar for the next three years, where they unearthed the fossils, two of which turned out to be previously unknown species of prosauropods – kangaroo-sized plant eaters with long necks that could walk on two or four legs. Prosauropods could be the early ancestors of sauropods like Apatasaurus, the most massive dinosaur.

In addition to the fossilized jaw bones, the team also discovered remains of eight other prehistoric animals of the same period. The scientists have not yet given formal names to their new finds, but geologist Andrew Wyss (University of California at Santa Barbara), who worked on the study, said some of the names would honor local residents – such as Mena, who found the fossil bed.

Seventy-seven thousand years ago, beings living in a cave about 280 kilometers (180 miles) east of Cape Town, South Africa, made tools. They also etched patterns of triangles in polished stone. According to some scientists, these actions show that the cave dwellers were thinking in a modern way – modern enough to create art. Well, at least some scientists think so. In fact, this claim has added fuel to one of anthropology’s most heated debate questions: When and where did modern humans start thinking in a "modern" way?

Before the South African cave findings, many researchers believed that modern human thought began somewhat suddenly about 40,000 years ago in Eurasia (Europe and Asia). Proof is the development of shaped bone tools and of sophisticated crafts that culminated in some spectacular cave paintings in Western Europe – works that continue to impress artists today.

Other scientists argue that modern behavior began much earlier in Africa. Recent advances in genetics have demonstrated that anatomically modern humans came "out of Africa" about 100,000 years ago and spread northward to Europe.

One Harvard University professor, Offer Bar-Yossef, stands in the middle of the debate: The cave dwellers, he says, "lived in isolation in a world with few people, where what they did either wasn’t accepted or wasn’t noticed, and then they went extinct."

That the dinosaurs became extinct after an asteroid plowed into Earth seems to be part of common knowledge these days (though it’s still a theory). But the details are starting to get a bit juicy, sort of like what happens on extreme TV. It’s bad enough that the poor dinosaurs had to get "conked on the head" by an asteroid, but now a team of American oceanographers says that the dinosaurs might have perished in a gas-fueled firestorm of unimaginable intensity! Yeeow, that’s a hideous thought!

The researchers believe that an impact of a giant asteroid or comet in the Gulf of Mexico would have generated huge shock waves that would have traveled around the planet and freed vast quantities of trapped methane (an odorless, colorless, flammable gas). Some 65 million years ago, in the Cretaceous Period, huge amounts of methane were trapped in sediments more than 500 meters below sea level. At these depths, low temperature and high pressure allow methane to combine with water to form solid methane hydrates. The cosmic collision would have tossed this methane hydrate into the air. Lightning bursts in the disturbed atmosphere would have ignited the methane-rich air and turned the entire atmosphere into a blazing inferno. This situation certainly wouldn’t have been good for the dinosaurs, who would have ended up overcooked.

If Italian researchers are correct, Ötzi, the Stone Age man discovered in a glacier in the Austrian Alps, died after suffering wounds in a knife fight. That’s the latest dirt on this 5,300-year-old mummy, which German hikers discovered by accident in 1991. Ever since that discovery, scientists have argued about how the 46-year-old man died. Some thought he froze to death while crossing the glacier. Others said that he was attacked from behind and that he bled to death after an arrow pierced his back. Others postulated that he was a ritual sacrifice.

One thing is certain: When Ötzi died, he had an assortment of weapons, including a dagger, bow and arrows, and an axe. Ötzi also had some suspicious wounds. According to a recent report in New Scientist magazine, x-rays and microscopic imaging performed by Eduard Egarter-Vigl, the mummy’s official caretaker (South Tyrol Museum of Archaeology in Bolzano, Italy) show a deep, zigzagging cut to the mummy’s hand.

Italian researchers now believe that this cut, and another to his wrist, may in fact be knife wounds that Ötzi received while defending himself from a violent attack. If so, it’s possible that Ötzi died within hours after receiving these, and perhaps other, mortal wounds. But archaeologist Konrad Spindler (University of Innsbruck, Austria) disagrees. He scrutinized every aspect of the iceman before the body was moved to Italy. "His injuries were not life-threatening," Spindler told New Scientist. "He had a cut on his hand and a non-deadly arrow insertion in his back. I believe he was attacked on familiar ground, fled from his pursuers, and climbed up into the Alps. Then he was surprised by an early snowfall and he froze to death. Above 3,000 meters, it is not possible to survive such weather."

If your vision of a dinosaur is one of a big, fat, lumbering beast, you’re right and at the same time wrong. After analyzing fossilized dinosaur footprints found in southern England, scientists discovered that Tyrannosaurus Rex and other bipedal therapods (flesh-eaters) sure could run!

Paleontologist Julia Day (Cambridge University, England) and her colleagues calculated that these beasts could sprint for short bursts at speeds of up to 30 kilometers per hour! When not running, therapods would walk pigeon-toed with wide steps at about 6 kph. But when they ran, the beasts would splay their toes and put one foot directly in front of the other.

The findings shed new light on the evolution of dinosaur locomotion and could have implications for biomechanics – the study of movement and physics as it applies to biological systems. One thing of which Day isn’t quite sure is how long the dinosaurs could keep up such a fast pace. Unfortunately (or perhaps fortunately!), she won’t be finding out firsthand.

The largest meat-eating dinosaur to terrorize the Earth might not have been Tyrannosaurus rex, but a needle-nosed, razor-toothed beast. At least that’s what fossils dug up in Patagonia, a desert on the eastern slopes of the Andes in South America, reveal.

Philip Currie of the Royal Tyrrell Museum in Alberta, Canada, recently co-discovered the new species, a giant (becoming the new champion at 12.5 meters long). While the infamous T. rex could crush its prey with brute force, this latest find preferred to slice and dice its dinner. With a tail and short front legs that were basically worthless, it was the beast’s long, narrow skull and jaw shaped like scissors that made it tougher than the rex. According to the researchers who unearthed the fossils, these monsters could have dissected their prey with almost surgical precision!

Initial counts indicate that as many as six separate creatures met their demise at the paleontological site. This fact has changed the way investigators view a dino’s daily interaction. No longer do scientists consider all prehistoric hunters to be loners. Evidence is mounting that these predators were members of deadly gangs. "You always think of these things as being solitary," says Currie. "Now we know that they traveled in packs."

A dinosaur dig led by Joshua Smith (University of Pennsylvania) about 290 kilometers southwest of Cairo, Egypt, has unearthed remnants of one of the largest dinosaurs ever discovered. Meet Paralititan stromeri, a fleshy sauropod (large, semiaquatic dinosaur) that must have measured close to 30 meters long and weighed almost 73,000 kilos. That’s not big enough to claim a record, but it does place Paralititan stromeri a close second to the current record holder, Argentinosaurus.

The team recovered Paralititan from fine-grained sediments at a fossil-rich oasis in the Sahara desert – one that for some reason fossil hunters had ignored ever since a German paleontologist, Ernst Stromer von Reichenbach, had found four new species of dinosaur there 60 years ago. Actually, Smith’s discovery was a chance one. "I had my head hanging out of the window," he says, "and we just drove past it." ("It" was a large bone lying in three pieces on the ground.) "If I had been looking the other way, there would have been no Paralititan discovery. We were very lucky indeed." Smith named the new dinosaur in Stromer’s honor: Paralititan stromeri means "Tidal Giant of Stromer."

The sediments also contained abundant plant remains, fossils of ancient turtles, crocodiles, and fish. Smith and his co-authors thus propose that this now-arid region may once have resembled Florida’s tropical mangrove coasts.

This dino discovery is superlative in several ways. Paralititan is one of the heaviest dinosaurs known to have lived. It is the first dinosaur known to have inhabited mangroves. And it is the first new dinosaur discovered in Egypt since 1939.

Here’s a factoid – at the end of the Permian period 250 million years ago, 95 percent of species were wiped out and Europe became a desert. It’s been known that land plants didn’t fare well during that pervasive blowout event. Now geologists, who have been weeding out the details of the cataclysm in ancient river beds in the Karoo basin of South Africa, have found some new evidence that has pollinated some new ideas.

It appears that streams in the Karoo region changed suddenly at the same time of the mass extinction. The streams went from the ol’ meandering pattern typical in well-vegetated zones to the braided pattern found in areas lacking deep-rooted vegetation to hold the soil together. Peter Ward of the University of Washington says that something curious happened here. Something killed all the plants throughout the region. Without the plants’ roots to hold the soil together, rapid erosion occurred.

So what caused the plants to pull up their roots and leave? [How’s that for a mixed (-up) metaphor?] What Ward concludes is that the underlying cause remains a mystery.

For years, scientists have been fishing around for evidence that the ancestors of land animals crawled out of the sea between 335 million and 365 million years ago. A fossil collected, until now, had lain forgotten in a British Museum — may provide it.

Meet Pederpes ("rock crawler"), a fossilized, four-legged animal (a tetrapod) that dates to around 345 million years ago in the Devonian period. It is the only intact skeleton from this critical time period ever unearthed! Pederpes looks sort of like a meter-long (3-foot-long) crocodile with a whip-like tail and lumbering legs. As paleontologist Jennifer Clack (University Museum of Zoology in Cambridge, England) told New Scientist magazine, "It’s by far the earliest leg that looks like it could have been used on land." The creature even has five toes on each foot.

Prior to 335 million years ago, tetrapods had limbs that allowed them to paddle but not walk. Thirty million years later, tetrapods were running all over the land.

Pederpes lies somewhere in between: It had the sensory apparatus of a fish, but limbs and feet adapted for life on solid ground. Now Clack and other researchers hope that by studying the bone structure of Pederpes, we will soon discover how aquatic animals evolved into land animals.

The cradle of life may have been a sulfurous, subterranean inferno, not unlike a medieval vision of hell. How’s that for an opening line?

Actually, those aren’t my words. They’re a direct quote from Birger Rasmussen, a paleobiologist at the University of Western Australia. It turns out he and his colleagues found the world’s oldest "submarine" fossils in Australian rock that used to be submerged in a volcano-heated ocean. The findings – 3.2-billion-year-old fossils of single-celled organisms – are 600 million years younger than the earliest chemical evidence of life on Earth and 2.7 billion years younger than other fossil evidence of submarine microbes.

The significance of the find is big, but the fossils aren’t. The threadlike organisms measure a thousandth of a millimeter in diameter and a tenth of a millimeter long, like wisps of human hair. They must have used chemical energy, perhaps derived from sulfur (which is common in hot spring water), rather than sunlight, to grow. Such environments could have provided a safe setting for life hundreds of millions of years before Earth’s surface was habitable. In fact, it appears that life on Earth began near hydrothermal systems, areas where underground volcanoes release hot, nutrient-rich water – not too far removed from that medieval vision of hell.

This just in from England: scientists have discovered the world’s oldest fossilized vomit.

While digging around some clay deposits in Peterborough, England, Peter Doyle and Jason Wood (Open University) discovered a mass of beastly barf that dates to some 160 million years ago. Upon closer inspection (ugh!), the scientists determined that the fossilized puke contains the shells of belemnites – squidlike shellfish. These belemnites were probably devoured by an ichthyosaur, a large dolphin-like marine reptile (related to land-dwelling dinosaurs) that swam the warm seas of the Jurassic era.

The problem with eating belemnites, though, is that their bullet-shaped shells would have caused damage to the ichthyosaur’s soft intestinal lining when swallowed. So the shells probably weren’t excreted as droppings. "The only alternative," Doyle observes, "is that the shells were vomited out, in much the same way that modern-day sperm whales regurgitate the indigestible beaks of birds they have eaten."

Further proof came after Doyle inspected the shells under a powerful scanning electron microscope, which revealed "acid etching" marks caused by digestive fluids from the stomach of a marine reptile, proving that the belemnites had been eaten by a predator. "This is the first time the existence of fossil vomit on a grand scale has been proven beyond reasonable doubt," said Doyle.

It’s no secret: the largest known mass extinction event occurred 250 million years ago. That’s when some 95 percent of all marine species and 70 percent of all land species vanished from the face of the Earth. Just what caused this catastrophic event has been "hotly" debated over the years. Some scientists blame asteroid or comet impacts, others the rise and fall of sea levels. More recently, a lot of attention has focused on the possibility that massive floods of lava over hundreds of thousands of years could have led to the extinction. And evidence continues to mount in favor of the lava-flood scenario.

This ancient "hot spot" of activity is centered on a cold region in Russia called the Siberian Platform – where some 2 million square kilometers of volcanic rock (called the Siberian Traps) has been uncovered. When scientists saw such a vast expanse of lava, they did not have to think hard about the consequences of such activity. The gases released into the atmosphere alone during such a prolonged and massive surge of volcanic activity could have led to the extinction. Now Marc K. Reichow (University of Leicester in England) and his colleagues have found evidence that the lava flows in the Siberian Platform are at least twice as extensive as previously believed! The new findings suggest that the Siberian Traps in fact covered almost 3.9 million square kilometers, an area approximately half the size of Australia. So the stakes have doubled in favor of a mass extinction fueled by lava.

You’ve seen it in movies such as "Jurassic Park," or in paintings hanging in museums, or in illustrated books. The "it" refers to a long-necked dinosaur, head raised like a swan, nibbling on vegetation atop the tallest trees. That image makes sense, right? Why else would a dinosaur need such a long neck? Certainly not to give it an advantage in a race.

But science is infamous for turning the tables on the obvious. Just look at some of the latest work by Kent A. Stevens, a professor in the Department of Computer and Information Science at the University of Oregon, and his colleague J. Michael Parrish of Northern Illinois University. These researchers have been using computers to create 3-D models of dinosaur-feeding posture. (Think of it as "cyberpaleontology," or using computers to assist in paleontological studies.) After reconstructing the bone and muscle structure of two long-necked dinosaurs (Diplodocus and Apatosaurus), these cyberpaleontologists have discovered that long-necked dinosaurs, or sauropods, couldn’t flex their necks in ways many scientists once believed. It turns out that the muscle and bone structure of these large animals didn’t allow for much head-lifting, at least not at the steep angles we often see portrayed.

So it appears that our long-necked friends didn’t pine after those luscious leaves atop the tallest trees after all. Instead, Stevens and Parrish suggest that the animals held out their necks nearly straight (parallel to the ground), angling them down to browse low-growing shrubs. See what fun you can have with computers and science!

We’ve had it wrong for more than a century. That’s what Lawrence Witmer and his clan of dinosaur researchers at Ohio University say about the placement of dinosaur noses in modern reconstructions.

"We found an extraordinary amount of evidence to suggest that the nostrils of dinosaurs actually were parked out front," Witmer says, meaning at the front of their long snouts, not back near the eyes, as was previously believed.

Witmer’s evidence can be seen in the noses of modern-day relatives of dinosaurs – namely, 62 animals from 45 species of crocodile, bird, and lizard – all of which have characteristic markings etched into bones by their soft tissues. By comparing these "signatures" with similar markings on dinosaur fossils, Witmer was able to map the likely positions of the cartilage, blood vessels, and other soft tissues making up a dinosaur’s nasal cavity. His conclusion: Dinosaur nostrils were more likely to have been on the front of their heads.

The old view on dinosaur noses was based largely (pun intended) on the assumption that giant sauropods (like the long-necked brontosaurus) probably had nostrils high on their forehead to allow them to breathe while partially submerged. And since the nasal opening in the skull was near the top of the head, the nose must have been there, too.

"Later scientists realized that the huge dinosaurs were perfectly capable of living on land." said Witmer, "But we never thought about the nose again. We left it on top of the head and never moved it."

"This is a solid piece of work," says Paul Sereno, a University of Chicago dinosaur expert. Putting the nose farther front, he says, makes sense. Witmer proposes that the dinosaur noses in pictures and models be moved to where he thinks nature actually put them – on the end of the snout. Other scientists agree. It just smells right.

Scientists working in South Africa have discovered the skull of a woman believed to be 1.8 million years old. It’s the most complete skull of an early hominid so far to be unearthed. The skull belongs to a female Australopithecus robustus (say that five times fast). Retired geologist Andre Keyser of the University of the Witwatersrand found the skull, which was just a few kilometers away from Sterkfontein Caves, the location of many early hominid finds.

A separate news item announces that one of the earliest human inventions was a toothpick! Homo erectus, and maybe the old woman discussed above, used this invention 1.8 million years ago. The toothpick was actually not seen but inferred. A tooth from the famous Olduvai Gorge site in Tanzania bears a series of tiny parallel lines scraped by a sharp, thin object pushed into the narrow space between teeth. Early humans probably adopted toothpicks when they started eating meat. In case you’re wondering, modern chimpanzees and gorillas do not use toothpicks!

Okay, you’re not going to believe it. I mean, will it ever end, this bird-dino debate? Imagine, we devoted an entire issue of ODYSSEY (September 2000) to dinosaurs. Exhaustive research on all manner of feathered fossils led scientists to a unanimous opinion – that birds descended from dinosaurs. "Yeah, right," you say.

Well, surprise, surprise! A recent study of a feathered fossil discovered in the former Soviet republic of Kyrgyzstan in 1969 by John A. Ruben has plucked the dino-bird of its feathers. A team of scientists from Oregon State University announced recently that dinosaurs evolved from reptiles, not birds.

What’s the evidence? Well, according to the reputable magazine Science, the evidence came from a study of the world’s most complete fossil of the little lizard Longisquama insugnis, which was on exhibit at a shopping mall in Kansas City, MO, giving researchers the opportunity to study it. (I bet many visitors never got to see it beyond the heads of researchers peering at it through a glass case.)

Anyway, what makes this specimen so interesting is that it has eight pairs of long appendages, each with features resembling feathers. The critter has an age of about 220 million years, so it hails from the early Triassic, which began 245 million years ago. So our little lizard is 75 million years older than the first known birdlike dinosaur, Archaeopteryx. Of course, the news has got a lot of researchers "down." I mean, how can this be? Well, you might have guessed the outcome: Other paleontologists have criticized the critter, arguing that the structures are scales, not feathers.

Reconstruction of Archaefructus sinensis (Science)

The plants we grow and love in the rich soil on Earth may have their origins under the sea. That’s the news from China, where scientists have discovered the oldest, most complete flowering-plant fossil yet. It is one of the most important flower discoveries in modern times. Ge Sun (Jilin University in China) and his colleagues discovered the 125-million-year-old fossil, which they dubbed Archaefructus sinensis. Analysis of the new plant species suggests that today’s flowering plants (called "angiosperms") may have evolved from weedy aquatic herbs.

The aquatic fossil plant, which resembles seaweed, has leaves typical of an aquatic plant, but with characteristics unique to flowering plants on land. Although Archaefructus sinensis actually lacks flowers, it does have seeds within the female reproductive organs, which is a characteristic of flowering plants. So Archaefructus sinensis may be a sister group to all existing flowering plants on Earth.

Picture this: You’re in the woods looking at two sets of footprints in the mud. You know your wildlife and quickly deduce that they belong to a bear and a coyote. The difference between the sets of prints is obvious. Now imagine that the footprints were left behind by two different kinds of birds. Would you be able to tell which species of bird left which set of prints? No, especially if you consider a big juvenile bird of one species can make the same size print as a small adult bird of another species. And that’s exactly what geologist James Farlow (Indiana University and Purdue University, Fort Wayne) says about identifying the species that created any set of dinosaur footprints. We can’t!

Farlow started out by looking at bird prints. He first made emus (those ostrich-like birds) run across a smooth, soft field at his local zoo. Next, he took measurements of the distance between the prints and made casts of them. He then did the same with other species of birds. He ended up with hundreds of prints made from over 40 different species. Farlow then examined the sets of prints the same way a scientist would scrutinize sets of dinosaur footprints. When Farlow tried to group the prints according to the birds that made them, he couldn’t.

"I went into this project looking for a magic key to assign footprints to their makers," Farlow says, "but it’s eluded me." The simple conclusion is that it just can’t be done. Farlow says this means scientists will never be able to tell whether a dinosaur print was made by an adult of one species or a juvenile of another, or to tell the difference between similar dinosaurs with overlapping geographic ranges. This sad finding ruins hopes that dinosaur tracks could be used to reveal how the animals lived.

It sounds like a lot of bull, but some researchers believe that sauropod (plant-eating) dinosaurs with enormously long tails like that of Apatosaurus (formerly Brontosaurus) used them not as defense mechanisms – like a slapper – but like bullwhips, or noisemakers. If you’ve ever heard a lion tamer snap his whip, you’ll agree that the noise certainly commands attention. In essence, that "snap" is a small sonic boom. The same happens when you flick that kitchen towel at your younger brother or sister as you’re doing the dishes.

The 25-meter-long Apatosaurus had a big bullwhip tail roughly a meter wide at its base, and the width of a human thumb at the end. The last few yards of tail were made up of rather small, fragile bones and weighed less than a pound. Now, Nathan P. Myhrvold of Microsoft Research in Redmond, Washington, and Philip Currie (Royal Tyrrell Museum in Canada) have developed computer models of that long sauropod tail and snapped it many times in virtual space. Their computer simulations show that a wave traveling from one vertebra to the next down such a tail could ultimately reach a speed of 2,000 kilometers per hour, which is fast enough to generate an enormous sonic boom. At an estimated 200 decibels, its loudness would rival that of a massive naval gun. "We cannot prove that supersonic tail-cracking occurred, but it is physically feasible," Myhrvold says.

Hmm. Sounds impressive. But why would a sauropod want to snap its tail . . . boredom? To keep a beat? The researchers argue that the noise was a way to communicate. Sauropods grazed over enormous tracts of land, so it’s possible to imagine them creating the loud booms to let other sauropods know where they were. But wouldn’t that attract the flesh-eaters, too? (Not to mention cause smaller animals to have heart attacks?!)

Okay, Myhrvold says. Maybe only the males used the whip-snapping to attract females, or to establish dominance. You know: My snap is louder than yours, so keep away. Or, "maybe," Myhrvold says, "it was big guys making loud noises for love." Sounds pretty strange to me. But Myhrvold insists it’s true: "I am now more convinced than ever."

Who can help it? Say the word "dinosaur" and visions of building-size animals come to mind. But evidence is growing that some big dinosaurs have tiny ancestors. Take for instance the famous horned dinosaur, Triceratops. Well, the remains of a newly discovered dinosaur species, a hare-size animal called Liaoceratops yanzigouensis, appears to be a distant cousin of Triceratops. But rather than weighing ten tons and being studded with massive horns and a wide frill, like Triceratops, the new dinosaur weighed only about 3 kilograms and had only hints of horns and a frill. In fact, Liaoceratops is the smallest, oldest, and most primitive neoceratops (the main line of horned dinosaurs) ever found.

Peter Makovicky (assistant curator of dinosaurs at the Field Museum in Chicago) and colleagues found the fossils in China, in rocks that date to 124 to 145 million years ago. Actually, all they found were two skulls: one belonged to a young Liaoceratops; the other, to an adult. But the scientists learned a lot from the skulls.

Liaoceratops, they deduced, must have stood about 30 centimeters tall and measured less than a meter long. The creature had two horns, one facing sideways under each of its eyes. But Makovicky doubts that the horns evolved for defense purposes. "Liaoceratops appears unable to protect itself against most predators, which would have included carnivorous dinosaurs and crocodiles," he says. "Instead, it probably relied on concealment or flight to defend itself."

Though not nearly so menacing as its well-known cousin, Liaoceratops does shed new light on the evolution of horned dinosaurs (the ceratopsians). "This small, primitive dinosaur is actually more interesting to science in many ways than its larger, more famous relatives because it teaches us more about evolution," says Makovicky. Long ago, ceratopsians branched into two lines: neoceratopsians, the main line that includes Triceratops, and psittacosaurids, parrot-beaked dinosaurs.

"Liaoceratops establishes that this split occurred no later than the earliest part of the Cretaceous Period about 130 million years ago," Makovicky says. "Also, it indicates that ceratopsians acquired some of their distinctive features earlier and more rapidly than was previously recognized. Liaoceratops demonstrates that the large, spectacular species that grace many museum exhibits are descended from some very small ancestors."

Michael Brett-Surman, a paleontologist at the Smithsonian Institution’s National Museum of Natural History in Washington, D.C., is advising museums across the world to check for bone damage at their most popular dinosaur fossil exhibits. The culprit? Chemical corrosion by you, and you, and you, and you, and millions of others like you, who visit museums each year.

Some of the world’s best-loved dinosaur skeletons, Brett-Surman says, are cracking up due to the moisture from visitors’ breath and local vibrations. Brett-Surman became alarmed at the danger when he noticed that a Triceratops skeleton on exhibit since 1905 at the Smithsonian museum had been seriously damaged in this way.

Anyway, Brett-Surman revealed that the problem is most severe where fossils have been displayed for decades in an open area without climate control. "It’s a misconception that a fossil is a rock," he said. "Fossils are very fragile." With seven million visitors a year exhaling inside the Smithsonian museum, humidity can reach 95 percent. That moisture encourages iron and sulfur minerals to form unstable iron sulfides, causing fossils to crumble with "pyrite disease." (Gasp! Sounds like something your dentist would like to sink his drill into.)

And speaking of drills, the reason the skeleton’s bones are rattling when you walk by is because the displays are mounted on metal rods without pads, so they transmit vibrations from visitors’ feet and passing traffic outside the building. This has caused the bones to develop cracks and crumble.

The solution? Did Brett-Surman suggest that everyone carry breath mints to the museum? No, the sad ending to this scoop is that the Triceratops skeleton will have to be repaired, then retired. A lighter cast will replace it in the open display, with the original skull mounted nearby in a transparent, humidity-controlled case. Well, I guess I have no choice but to end this scoop by saying . . . "Case closed."

The fossilized remains of a gargantuan crocodile, the largest in the world, were recently discovered in the Tenere Desert of Niger in West Africa. Sarcosuchus (pronounced SARK-oh-SOOK-us) imperator, which means "flesh crocodile emperor" was a river dweller that measured some 12 meters in length and must have weighed up to 9 metric tons – that’s 10 to 15 times more massive than the largest existing crocodile, and the size of a tractor-trailer.

The big guy, who lived 110 million years ago, had a massive, bulbous growth at the end of its snout – one of the scientists said it resembled a huge, scaly toilet bowl – and enjoyed a remarkably long life span of up to 60 years. Dinosaur digger Paul Sereno (University of Chicago), who led the research team that discovered Sarcosuchus, said it was so large and fearsome that it would have "given dinosaurs nightmares."

Sarcosuchus may have been the heftiest meat-eater living during the Cretaceous Period. Sereno said that the huge reptile could ambush and feast upon even large dinosaurs – especially those who were thirsty and came to a river for a drink.

"All 10 tons of it would have been hidden, minus the eyeballs, prior to an attack," Sereno said.

Sarcosuchus is not a direct ancestor of modern crocodiles, but a close cousin. It most closely resembles India’s endangered Gharial crocodiles, which, like their huge ancient relative, possess a rounded, bony mass at the tip of a long snout. The jaws of Sarcosuchus were also impressive, armed with more than 100 teeth, including a row of enlarged, bone-crushing incisors. Now, I’d like to see a crocodile hunter such as Steve Irwin wrestle and rope Sarcosuchus – if he said he could, well, now that would be a big croc of bull!