Tag: "asteroid" at biology news
New evidence indicates biggest extinction wasn't caused by asteroid or comet
...ce has been building that the impact of a comet or asteroid
triggered the biggest mass extinction in Earth his...in the Karoo that would indicate a body such as an asteroid
hit around the time of the extinction, though they looked specifically for impact clays or material ...
USGS featured at AAAS - Nation's largest science meeting
...th, Workshop Room E About 35 million years ago, an asteroid
or comet nucleus measuring about 1-1/2 miles in diameter collided with the Earth at the mouth of Chesapeake Bay. The force of this collision was so great that it vaporized hundreds of feet of seawater and blasted sediments forming a 53-mile-diameter...
Comparative chromosome study finds breakage trends, cancer ties
... believed to have resulted from a massive comet or asteroid
strike. The study's data, Murphy added, provide a potential link between post-K-T isolation and the accelerated development of species-specific chromosomes. Since the K-T extinction, rates of chromosomal evolution among the species have increased fro...
Multi-species genome comparison sheds new light on evolutionary processes, cancer mutations
...s thought to have resulted from a massive comet or asteroid
striking Earth, mammals shared fairly similar body plans and also fairly similar genomes. Researchers speculate that the mass extinction opened new ecological niches for mammals, spurring their diversification and the emergence of new mammalian order...
Greenhouse theory smashed by biggest stone
...ngus Meteorite is thought to have resulted from an asteroid
or comet entering the earth's atmosphere and explo...at only an enormous natural phenomenon, such as an asteroid
or comet impact or airburst, could seriously disturb atmospheric water levels, destroying persistent...
Lunar rocks suggest meteorite shower
...interval possibly the result of collisions in the asteroid
belt with comets coming from just beyond our solar...nd small planet bodies, inducing collisions in the asteroid
belt. The close passing of a neighboring star could have had a similar effect." Duncan and his coll...
'Banana-jawed' fossil mammal linked to rare sound-producing skill
...s diversified and became larger only after a giant asteroid
killed off the dinosaurs 65 million years ago. Numerous ecological niches vacated by the annihilated dinosaurs were waiting to be filled. One group of creatures, called the Afrotheres -- "Beasts from Africa" -- seized the opportunity. It was from thi...
A sea otter-shaped rubble pile in space
... "falcon" in Japanese, hovered over the near-Earth asteroid
Itokawa last fall, taking up-close measurements an...n Science give us an intimate look at a near-Earth asteroid
and provide information on its makeup and relation to collected meteorites. The Hayabusa misson also...
Dramatic shift from simple to complex marine ecosystems occurred 250M years ago at mass extinction
...o, prior to the explosion of animal diversity. The asteroid
that wiped out the dinosaurs couldn't manage that." Lidgard added, "When Pete walked into my office with his preliminary results, I simply couldn't believe them. Paleontologists had long recognized that ecosystems had become more complex, from the o...
No need to thank dinosaur-killing asteroid for mammalian success
... Earth for hundreds of millions of years, until an asteroid
struck the Yucatan Peninsula and triggered a mass ...d the ancestors of todays mammals to thrive. The asteroid
part of the story may still hold true, but a new study published in the March 29 issue of the journa...
The delayed rise of present-day mammals
...dinosaurs and many other large animals when a huge asteroid
crashed into the Earth about 65 million years ago. An international research team reached that conclusion after analysing the evolutionary links of some 4,500 mammals, creating for the first time a "supertree" of family relationships between almos...
Oregon researchers involved in new Clovis-age impact theory
...en numerous species were wiped out after a massive asteroid
is believed to have struck Mexico's Yucatan Peninsula and the Gulf of Mexico. Missing in the new theory is a crater marking an impact, but researchers argue that a strike above or into the Laurentide ice sheet could have absorbed it since it was le...
Caribbean frogs started with a single, ancient voyage on a raft from South America
...y rafting across the Caribbean Sea after the giant asteroid
impact near Cuba 65-million years ago, which is wi...cient and successful dispersals happened after the asteroid
collision rather than earlier. "The asteroid
impact generated giant waves that devastated the islan...