Agriculture
Hungry bug seeks hot meal
Springing forward
Got Milk? How?
Amphibians
Salamanders
Bullfrogs
Salamanders and Newts
Animals
Feeding School for Meerkats
Poor Devils
Killer Flatworms Hunt with Poison
Behavior
Between a rock and a wet place
The Disappearing Newspaper
Primate Memory Showdown
Birds
Parakeets
Waterfowl
Owls
Chemistry and Materials
Meteorites may have sparked life on Earth
These gems make their own way
The hottest soup in New York
Computers
It's a Small E-mail World After All
Music of the Future
Troubles with Hubble
Dinosaurs and Fossils
Feathered Fossils
Early Birds Ready to Rumble
An Ancient Feathered Biplane
E Learning Jamaica
2014 GSAT Results for Jamaican Kids
Results of GSAT are in schools this week
E Learning in Jamaica WIN PRIZES and try our Fun Animated Games
Earth
Earth from the inside out
Farms sprout in cities
Life trapped under a glacier
Environment
An Ocean View's Downside
The Birds are Falling
The Wolf and the Cow
Finding the Past
The Puzzle of Ancient Mariners
A Long Trek to Asia
Meet your mysterious relative
Fish
Halibut
Bass
Perches
Food and Nutrition
Symbols from the Stone Age
Chew for Health
Sponges' secret weapon
GSAT English Rules
Who vs. Whom
Adjectives and Adverbs
Order of Adjectives
GSAT Exam Preparation Jamaica
Results of GSAT are in schools this week
Mastering The GSAT Exam
GSAT Exam Preparation
GSAT Exams Jamaica Scholarships
Access denied - Disabled boy aces GSAT
GSAT stars reap scholarship glory
GSAT Practice Papers | GSAT Mathematics | Maths
GSAT Mathematics
How a Venus Flytrap Snaps Shut
How to Slice a Cake Fairly
Secrets of an Ancient Computer
Human Body
A Long Trek to Asia
The tell-tale bacteria
Taste Messenger
Invertebrates
Millipedes
Hermit Crabs
Centipedes
Mammals
Cornish Rex
Kangaroos
Rabbits
Parents
How children learn
Choosing a Preschool: What to Consider
The Surprising Meaning and Benefits of Nursery Rhymes
Physics
Project Music
The Mirror Universe of Antimatter
Strange Universe: The Stuff of Darkness
Plants
When Fungi and Algae Marry
Springing forward
Farms sprout in cities
Reptiles
Garter Snakes
Crocodiles
Crocodilians
Space and Astronomy
Pluto, plutoid: What's in a name?
A Moon's Icy Spray
World of Three Suns
Technology and Engineering
A Satellite of Your Own
Are Propellers Fin-ished?
Young Scientists Take Flight
The Parts of Speech
What is a Verb?
What is a Preposition?
What is a Noun
Transportation
Tinkering With the Basic Bike
Are Propellers Fin-ished?
Troubles with Hubble
Weather
In Antarctica watch the heat (and your step)
Weekend Weather Really Is Different
Where rivers run uphill
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 HBJamaica.com™