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Impact didn't lead to mass extinction 65 million years ago, geologists findThe enduringly popular theory that the Chicxulub crater holds the clue to the demise of the dinosaurs, along with some 65 percent of all species 65 million years ago, is challenged in a paper to be published in the Journal of the Geological Society on April 27, 2009. The crater, discovered in 1978 in northern Yucutan and measuring about 180 kilometers (112 miles) in diameter, records a massive extra-terrestrial impact. When spherules from the impact were found just below the Cretaceous-Tertiary (K-T) boundary, it was quickly identified as the...

Volcanoes that erupted in India about 65 million years ago were instrumental in the extinction of dinosaurs, according to new research. For the last thirty years scientists have believed a giant meteorite that struck Mexico’s Yucatan Peninsula was responsible for the mass extinction of dinosaurs, the Daily Telegraph reported on Wednesday. But now Gerta Keller, a geologist at Princeton University, New Jersey, says fossilised traces of plants and animals dug out of low lying hills at El Penon in northeast Mexico show this event happened 300,000 years after the dinosaurs disappeared. Keller suggests that the massive volcanic eruptions at the...

Scientists have discovered a macabre death scene that took place 67 million years ago. The setting was a nest, in which a baby dinosaur had just hatched from an egg, only to face an 11-foot-long snake waiting to devour it. The moment was frozen forever when, apparently, the nest was buried in a sudden avalanche of mud or sand and everything was fossilized. Scientists have discovered a macabre death scene that took place 67 million years ago. The setting was a nest, in which a baby dinosaur had just hatched from an egg, only to face an 11-foot-long snake waiting...

Dinosaur Shocker By Helen Fields Neatly dressed in blue Capri pants and a sleeveless top, long hair flowing over her bare shoulders, Mary Schweitzer sits at a microscope in a dim lab, her face lit only by a glowing computer screen showing a network of thin, branching vessels. That’s right, blood vessels. From a dinosaur. “Ho-ho-ho, I am excite-e-e-e-d,” she chuckles. “I am, like, really excited.” After 68 million years in the ground, a Tyrannosaurus rex found in Montana was dug up, its leg bone was broken in pieces, and fragments were dissolved in acid in Schweitzer’s laboratory at North...

The big dinosaur extinction of 65 million years ago didn't produce a flurry of new species in the ancestry of modern mammals after all, says a huge study that challenges a long-standing theory. Scientists who constructed a massive evolutionary family tree for mammals found no sign of such a burst of new species at that time among the ancestors of present-day animals. Only mammals with no modern-day descendants showed that effect. "I was flabbergasted," said study co-author Ross MacPhee, curator of vertebrate zoology at the American Museum of Natural History in New York. At the time of the dinosaur demise,...

A dinosaur egg weighing more than five kilograms (11 pounds) and measuring 30 centimetres in diameter has been found in western India, government officials said. The egg was discovered by telecom workers digging in the town of Balasinor, in the south of Gujarat state. “Two feet from the ground, we struck an oblong stone. On breaking the stone, a football-sized egg was found. It is white with some orange spots on it,” said M.P. Patel, sub-divisional officer of the telecom department. Tara Mukundan, a collector from Kheda district, said officials from the Archaelogical Survey of India will collect the egg....

CHENNAI, India (Reuters) – Geologists have found a cluster of fossilized dinosaur eggs, said to be about 65 million years old, in a village in the southern Indian state of Tamil Nadu, according to media reports. > The clusters were under ash from volcanic eruptions on the Deccan plateau, which geologists said could have caused the dinosaurs to become extinct. >

Boulder, CO, USA -- A mysterious basin off the coast of India could be the largest, multi-ringed impact crater the world has ever seen. And if a new study is right, it may have been responsible for killing the dinosaurs off 65 million years ago. Sankar Chatterjee of Texas Tech University and a team of researchers took a close look at the massive Shiva basin, a submerged depression west of India that is intensely mined for its oil and gas resources. Some complex craters are among the most productive hydrocarbon sites on the planet. Chatterjee will present his research at...

Dinosaur Deaths Outsourced to India? Boulder, CO, USA - A series of monumental volcanic eruptions in India may have killed the dinosaurs 65 million years ago, not a meteor impact in the Gulf of Mexico. The eruptions, which created the gigantic Deccan Traps lava beds of India, are now the prime suspect in the most famous and persistent paleontological murder mystery, say scientists who have conducted a slew of new investigations honing down eruption timing. "It's the first time we can directly link the main phase of the Deccan Traps to the mass extinction," said Princeton University paleontologist Gerta Keller....

More than 65 million years after they went extinct, dinosaurs are about to disappear again — at least from public view in Washington. The Smithsonian’s National Museum of Natural History said Friday that its high-traffic dinosaur hall will close April 28 for a previously announced $48 million makeover. Most of the popular specimens won’t reappear until 2019, when the Fossil Hall at the world’s second-most-visited museum is reopened.

Travel back far enough in your genealogy, and you will run into a fish. Before about 370 million years ago, our ancestors were scaly creatures that lived in the sea, swimming with fins and using gills to get oxygen from the water. And then, over the course of millions of years, they began moving ashore, adapting to the terrestrial realm. They became tetrapods, a lineage that would eventually produce today’s amphibians, reptiles, birds, and mammals. As scientists have unearthed fossils from those early days, one lesson has come through ever more loud and clear: the transition was not a single...

The exceptionally well-preserved fossil primate known as "Ida" is not a missing link as some have claimed, according to an analysis in the journal Nature. The research is the first independent assessment of the claims made in a scientific paper and a television documentary earlier this year. Dr Erik Seiffert says that Ida belonged to a group more closely linked to lemurs than to monkeys, apes or us. His team's conclusions come from an analysis of another fossil primate. The newly described animal - known as Afradapis longicristatus - lived some 37 million years ago in northern Egypt, during the...

Scientists at the Georgia Institute of Technology have found genetic evidence that seems to support a controversial hypothesis that humans and chimpanzees may be more closely related to each other than chimps are to the other two species of great apes – gorillas and orangutans. They also found that humans evolved at a slower rate than apes. Appearing in the January 23, 2006 issue of the Proceedings of the National Academy of Sciences, biologist Soojin Yi reports that the rate of human and chimp molecular evolution – changes that occur over time at the genetic level – is much slower...

The brains of chimpanzees show a number of similarities to human brains, the results of two new studies suggest. Findings published in the December issue ofBehavioral Neuroscience indicate that the animals have differences between the right and left sides of their brains in much the same way that humans do. In addition, it appears that the neurological basis for handedness is not unique to our species. Hani D. Freeman of the Yerkes National Primate Research Center and his colleagues scanned the brains of 60 chimpanzees with magnetic resonance imaging (MRI) and measured two key regions of the brain's limbic system,...

By Clive Cookson, Science Editor Published: August 31 2005 18:46 | Last updated: August 31 2005 18:46 The first detailed genetic comparison between humans and chimpanzees shows that 96 per cent of the DNA sequence is identical in the two species. But there are significant differences, particularly in genes relating to sexual reproduction, brain development, immunity and the sense of smell. An international scientific consortium publishes the genome of the chimpanzee, the animal most closely related to homo sapiens on Thursday in the journal Nature. It is the fourth mammal to have its full genome sequenced, after the mouse, rat...

Despite decades of study, geneticists don't know what makes humans human. Language, long arms, and tree-climbing prowess aside, humans and our kissing cousins, chimpanzees, share practically all of our DNA. Genomic studies have suggested that the regulation of genes, rather than the genes themselves, set the two primate species apart. But genes are still an important part of the story, says Michele Cargill, a geneticist at Celera Diagnostics in Alameda, California. She and her colleagues found key differences between chimp and human genome coding sequences, differences that propelled human evolution and sometimes lead to genetic diseases. Genes for olfaction and...

Why the Y chromosome is a hotbed for evolution Mark Henderson, Science Editor The Y chromosome is often seen as the rotten corner of the human genome — a place of evolutionary decline that is slowly decaying and threatening the end of man. Reports of its imminent demise, however, have been exaggerated. Research has indicated that, far from stagnating, the male chromosome is a hotspot of evolution that is changing more quickly than any other part of humanity’s genetic code. In most mammals the sex of offspring is determined by X and Y chromosomes. Females have two Xs, males have...

A group of researchers from Korea and Japan has deciphered the Y chromosome of chimpanzees' genetic code, getting a step closer to solving the mysteries surrounding human evolution. It is well known that we share more than 98 percent of our DNA and almost all of our genes with the chimpanzee. Now the researchers have decoded more than half of the Y chromosomes, or 12.7 million base pairs, of man's closest living relative. "Because no genetic exchange occurs, the Y chromosome is important in explaining the evolution process," said Park Hong-seog, a senior researcher at the Korea Research Institute of...

Since the human-chimp split about 6 million years ago, chimpanzee genes can be said to have evolved more than human genes, a new study suggests. The results, detailed online this week in the Proceedings of the National Academy of Sciences, contradict the conventional wisdom that humans are the result of a high degree of genetic selection, evidenced by our relatively large brains, cognitive abilities and bi-pedalism. Jianzhi Zhang of the University of Michigan and his colleagues analyzed strings of DNA from nearly 14,000 protein-coding genes shared by chimps and humans. They looked for differences gene by gene and whether they...

The first-ever chimpanzee fossils were recently discovered in an area previously thought to be unsuitable for chimps. Fossils from human ancestors were also found nearby. Although researchers have only found a few chimp teeth, the discovery could cause a shake-up in the theories of human evolution. “We know today if you go to western and central Africa that humans and chimps live in similar and neighboring environments,” said Nina Jablonski, an anthropologist at the California Academy of Sciences. “This is the first evidence in the fossil record that they coexisted in the same place in the past.” It had previously...