Making the most of a meal
Hungry bug seeks hot meal
Earth-Friendly Fabrics
Poison Dart Frogs
Tree Frogs
Eyes on the Depths
A Butterfly's New Green Glow
Vent Worms Like It Hot
Honeybees do the wave
Slumber by the numbers
Swine flu goes global
Chemistry and Materials
Salt secrets
Supergoo to the rescue
Unscrambling a Gem of a Mystery
A Classroom of the Mind
A New Look at Saturn's rings
Music of the Future
Dinosaurs and Fossils
Feathered Fossils
Mammals in the Shadow of Dinosaurs
An Ancient Feathered Biplane
E Learning Jamaica
2014 GSAT Results for Jamaican Kids
E Learning in Jamaica WIN PRIZES and try our Fun Animated Games
Results of GSAT are in schools this week
Giving Sharks Safe Homes
On the Trail of America's Next Top Scientists
Plastic-munching microbes
Watching for Wildfires in Yellowstone
Catching Some Rays
Saving Wetlands
Finding the Past
Traces of Ancient Campfires
The Puzzle of Ancient Mariners
A Long Trek to Asia
Saltwater Fish
Freshwater Fish
Food and Nutrition
Building a Food Pyramid
Chocolate Rules
Recipe for Health
GSAT English Rules
Who vs. Whom
Adjectives and Adverbs
Capitalization Rules
GSAT Exam Preparation Jamaica
How are students placed after passing the GSAT exam
Results of GSAT are in schools this week
Preparing for the GSAT Exam
GSAT Exams Jamaica Scholarships
GSAT Scholarship
2014 GSAT Results for Jamaican Kids
GSAT stars reap scholarship glory
GSAT Mathematics
Math of the World
Math and our number sense:
10 Common Mistakes When Preparing for the GSAT Math Test
Human Body
Hear, Hear
Teen Brains, Under Construction
Opening a Channel for Tasting Salt
Camel Spiders
Horseshoe Crabs
Expert report highlights the importance to parents of reading to children!
How children learn
Children and Media
Project Music
Powering Ball Lightning
Electric Backpack
A Change in Leaf Color
Underwater Jungles
Farms sprout in cities
Copperhead Snakes
Space and Astronomy
Return to Space
Unveiling Titan
Saturn's New Moons
Technology and Engineering
Musclebots Take Some Steps
Model Plane Flies the Atlantic
Smart Windows
The Parts of Speech
Countable and Uncountable Nouns
What is a Verb?
Adjectives and Adverbs
Morphing a Wing to Save Fuel
Charged cars that would charge
Troubles with Hubble
A Change in Climate
Watering the Air
A Dire Shortage of Water
Add your Article

Island Extinctions

People arrived in Australia about 50,000 years ago. Soon after, many of the island's large mammals disappeared, new evidence suggests. Among the animals that went extinct were several species of kangaroos and wombats and some other creatures found nowhere else. Known as marsupials, these animals had pouches but filled ecological niches populated elsewhere by lions, hyenas, hippos, tapirs, and other large animals. This illuminating new look into the past comes from a group of caves in southeastern Australia. Fossils fill the caves, which lie 300 kilometers (186 miles) southeast of Adelaide. Researchers led by a paleontologist at the Western Australian Museum in Perth collected, identified, and dated fossils that covered some 500,000 years of history. The bones that they found belonged to 62 species of mammals that didn't fly. Most of these creatures fell into the caves through sinkholes in the ground. Owls brought in others. Previously, scientists had used icicle-like rock formations, called stalactites, to piece together a history of climate change in the area. When the weather was wet, water dripped down the stalactites, making them grow. During dry times, stalactite growth stopped. Over the past 500,000 years, the Perth scientists found, the number and types of mammals in the caves decreased only during long dry spells. The animals came back when the rains returned. Between 50,000 and 45,000 years ago, however, many of Australia's creatures that were cat-sized or larger disappeared, even though there was no major climate shift. The next ice age wouldn't begin for another 25,000 years. "The climate was stable then, and mammals really shouldn't have been going extinct," says Richard G. Roberts, a geochemist at the University of Wollongong in Australia. "The only thing that's new during that period," he adds, "is people." Scientists aren't yet sure how people might have caused the wave of extinction among large animals in Australia. People often burned much of the landscape, and some experts argue that animals died as fire destroyed their habitats. It's also possible that large species dwindled gradually as people hunted and ate them faster than they could reproduce. Whatever the explanation, the data are clear. People had a more profound effect on the lives (and deaths) of Australian animals than climate change did.E. Sohn

Island Extinctions
Island Extinctions

Designed and Powered by™