North America Hit Hard By Asteroid Strike In Yucatan 65 Million Years Ago
PROVIDENCE, R.I. -- All asteroid-based extinctions great and small are notalike. A new study says th...ire consequences of such animpact: The severity of extinctions that result from an object's impact onEarth may reflect the incoming object's angle. Editors: Colo...Impact of Meteorites, Drop in Sea Level Caused Mass Extinctions 65 Million Years Ago
...d-Cretaceous extinction is one of the largest mass extinctions in Earth's history, and its cause has been among t...steroid or comet, also may have caused some of the extinctions at the end of what is known as the Cretaceous period. Marshall and Ward present evidence demonstrat...Bigger Biology Tackled Through Keyboards
... certain viruses to thelong-term impact of species extinctions on global ecological processes. Fortunately, a relatively new field of science known as computational biologyis coming of age, according to a review paper in the Jan. 17 issue of theweekly journal Science by researchers from the University of Calif...Recovery From Mass Extinction Is Unexpectedly Diverse
...ist David Jablonski shows thatrecoveries from mass extinctions differ widely from one geographical region toanoth...g local species to foreigninvaders. "Maybe not all extinctions are created equal: it's not only how much you lose,but who," he said. Jablonski's findings may have......Triassic period–one of the five greatest mass extinctions inhistory. The work, by scientists at the University of Chicago , the University ofNew Brunswick (Canada) and The Open University (Milton Keynes, U.K.) ispublished in a paper in the Thursday, March 12 , issue of the journal Nature. “When sc...Gene Study Shows Mammals Lived Before Extinction Of The Dinosaurs
...studies, which link the evolutionary event to mass extinctions 65 millionyears ago. "This is the first time we ever have been able to estimate when all theselifeforms appeared on Earth," Hedges says. "Fossils can't give us thisinformation, partly because there are huge periods of Earth's history from whichnot...University Of Cincinnati Geologists Analyzes Evolutionary Impact Of Mass Extinctions
The dramatic effects of the mass extinctions recorded in Earth's geologicrecord haveled many ge...ic, in light of recentresearch, indicates thatmass extinctions are simply the most globally extensive of a continuum of abrupttransitions thatcombine to affect ove...Long Lava Flows May Have Taken Years, Causing Global Cooling And Extinctions
... dioxide. This cooling couldhave caused many major extinctions during the past 500 million years. Forexample, a major eruption in the North Atlantic might have wiped out mostdinosaurs by eliminating their plant food supply, even before the presumedasteroid impact that finished the job. The study is not ...Study Associates Asteroid Or Comet Impact With Extinctions In Argentina
...impact may have directly caused the regional extinctions or triggered a climatechange that led to the...een small enough to causeregional damage and extinctions and may have triggered a climate change. El Niñoor a volcanic eruption produces small t...Amphibian Revival: Build It And They Will Come
...er of European countries. In some cases, apparent extinctions haveoccurred. However, very few of the reports or studies have documented data ofmore than a few years. A team headed by Owen Sexton, Ph.D., professor emeritus of biology in Arts andSciences at Washington University, repopulated ponds at Tyson Resea...Studies Document Ease Of Ecosystem Disruption
...resses such asover-exploitation, increased species extinctions and climate change. "As we consider the impacts of global warming, many people assume theeffects will be gradual, a shift to new regions by various plant and animalspecies," said Eric Sanford, an OSU ecologist. "But this study shows that if y...Dinosaur fossils reveal evolution's big picture, says Paul Sereno
...hat this diversity arose as apatchwork of regional extinctions of certain species and replacements by others,not by the creation of new lineages, which has been considered as an alternativepossibility. Eventually, the dinosaurs met their demise at the end of the Cretaceous. ButSereno isn't letting the mystery of...Rainforest birds keep dying out long after logging stops
...ragmenthas been isolated and on the number of bird extinctions during that time. To check their method, they showed that it accurately accounts for thenumber of species that have been lost in eastern North America, wheredeforestation peaked 150 years ago. Brooks and his colleagues found that within 50 years of ...Biologist calls 30% of African primates 'living dead'
...heir forest primate species within decades. Actual extinctions could bemuch higher because West Africa is expected to lose 70% and East Africa 95% of the remaining forest cover by 2040. Habitat loss threatens about half of primate species worldwide. Determiningwhere the extinction debts are the greatest will he...One theory solves two ancient climate paradoxes
...ferent times. "Three glaciations would mean three extinctions for large numbers of species," says Jenkins. "To suggest that life made it through really hard times three times is really hard for me to believe." The global climate model for this period uses an Earth with somewhat more land mass, the 70-degree ti...Fertilizers linked to amphibian deaths
...re in the Pacific Northwest we're having localized extinctions of some amphibians and widespread declines in others. We now have clear evidence that nitrate and nitrite exposure at levels considered safe for humans or fish is enough to kill amphibians." Blaustein has done pioneering research on the potential i...Past climate change effects on mammals may mirror global warming impact
...on mammals will be tremendous. There will be local extinctions across the valleys of the Great Basin and into the mountains." The climate in the Great Basin, which includes most of Nevada and portions of California, Idaho Oregon and Utah, was different in the late Pleistocene and the early Holocene, the epoc...Complex mystery of amphibian decline calls for a new kind of science
...ny of the known cases, which include multi-species extinctions on nature preserves and other relatively pristine lands. Recently, Collins and other researchers have found evidence that a couple of different pathogens might also be involved -- one an iridovirus and the other a chytrid fungus. Both are from fami...New science resources available from the ESA
...al damage. Animal invaders for example, can cause extinctions of vulnerable native animals by preying upon them, consuming their food, or taking over their habitat. Plant invaders can completely alter the fire and nutrient cycles, and water and energy budgets in a native ecosystem. Such alterations can greatl......A single environmental catastrophe could result in extinctions of several of these species, due to their isolated distributions," he adds. Although several other research groups have predicted that species with higher local abundance will also have larger geographical ranges, Pyron did not find that to be true...