Agriculture
Protecting Cows—and People—from a Deadly Disease
Seeds of the Future
Growing Healthier Tomato Plants
Amphibians
Tree Frogs
Bullfrogs
Newts
Animals
Putting a Mouse on Pause
From Chimps to People
Odor-Chasing Penguins
Behavior
Eating Troubles
Primate Memory Showdown
Math is a real brain bender
Birds
Blue Jays
Ibises
Pelicans
Chemistry and Materials
Meteorites may have sparked life on Earth
Atomic Drive
These gems make their own way
Computers
Galaxies far, far, far away
New eyes to scan the skies
Play for Science
Dinosaurs and Fossils
Battling Mastodons
Did Dinosaurs Do Handstands?
Teeny Skull Reveals Ancient Ancestor
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
Earth
Earth's Lowly Rumble
Coral Islands Survive a Tsunami
Challenging the Forces of Nature
Environment
Watching for Wildfires in Yellowstone
Catching Some Rays
Indoor ozone stopper
Finding the Past
A Long Haul
Decoding a Beverage Jar
Ancient Art on the Rocks
Fish
Bass
Mako Sharks
Electric Catfish
Food and Nutrition
Symbols from the Stone Age
A Pepper Part that Burns Fat
Chew for Health
GSAT English Rules
Pronouns
Order of Adjectives
Finding Subjects and Verbs
GSAT Exam Preparation Jamaica
Tarrant High overcoming the odds
Results of GSAT are in schools this week
Mastering The GSAT Exam
GSAT Exams Jamaica Scholarships
2014 GSAT Results for Jamaican Kids
GSAT Practice Papers | GSAT Mathematics | Maths
42,000 students will sit for the GSAT Exam in two weeks
GSAT Mathematics
Math of the World
Deep-space dancers
Play for Science
Human Body
Germ Zapper
Hear, Hear
Cell Phone Tattlers
Invertebrates
Insects
Mosquitos
Bedbugs
Mammals
African Hippopotamus
Wolves
Skunks
Parents
Choosing a Preschool: What to Consider
The Surprising Meaning and Benefits of Nursery Rhymes
Raise a Lifelong Reader by Reading Aloud
Physics
Project Music
Extra Strings for New Sounds
Black Hole Journey
Plants
Tracking the Sun Improves Plant Pollen
White fuzzy mold not as friendly as it looks
When Fungi and Algae Marry
Reptiles
Box Turtles
Black Mamba
Geckos
Space and Astronomy
Killers from Outer Space
Zooming In on the Wild Sun
A Star's Belt of Dust and Rocks
Technology and Engineering
Searching for Alien Life
Squeezing Oil from Old Wells
Sugar Power for Cell Phones
The Parts of Speech
What is a Noun
What is a Preposition?
Adjectives and Adverbs
Transportation
Reach for the Sky
Middle school science adventures
How to Fly Like a Bat
Weather
Warmest Year on Record
The solar system's biggest junkyard
A Dire Shortage of Water
Add your Article

Stone Age Sole Survivors

The people who walked on a muddy lakeshore in southeastern Australia surely never suspected that their footprints would stick around for 20,000 years. Yet, at least 124 of their prints still exist, say a group of scientists who uncovered the barefoot impressions. It's the largest collection of Stone Age footprints ever discovered, and analyses are giving insight into the lives and bodies of the people who left them behind. The footprints were found in August 2003 during a general survey of the area's archaeology. Eighty-nine footprints were already exposed. A little digging in the soil turned up another 35. To figure out when feet last touched ground, the scientists aimed laser light on grains of sand taken from sediment just above and just below the impressions. These sediments, they figured, had to be at the surface when the people walked across the lakeshore. Light that bounced back from the sand grains provided information that allowed the scientists to estimate the age of the sand. (In particular, they looked at how much radioactivity had built up in the sediment.) They dated the footprints to between 23,000 and 19,000 years ago. The shapes and sizes of the prints and the distances between them allowed the scientists to figure out about how many people were there, how tall they were, and roughly how old they might have been at the time. Seventy-six of the impressions, they found, belonged to eight people. Six were fairly large adults. (Two measured more than 6 feet tall.) Two were younger. The adults ran across the muddy plain in one direction. A teenager and a child moved in the same general direction, but they walked. Comparisons of the prehistoric strides with the strides of similarly sized, modern distance runners showed that the largest of the adults was running at a speed of up to 12 miles per hour. That's about the speed of a fit runner today. Near the footprints, the scientists found many round indentations, measuring about 2 inches across. These could be the marks of weapons or walking sticks. Long, shallow grooves suggest that the people were also dragging poles. The group may have been moving from one lake or camp to another, the scientists speculate. Or perhaps they were out hunting or fishing—or even picnicking.—E. Sohn

Stone Age Sole Survivors
Stone Age Sole Survivors








Designed and Powered by HBJamaica.com™