Agriculture
Watching out for vultures
Making the most of a meal
Microbes at the Gas Pump
Amphibians
Salamanders
Frogs and Toads
Bullfrogs
Animals
Who's Knocking?
Return of the Lost Limbs
Sleepless at Sea
Behavior
Between a rock and a wet place
Honeybees do the wave
Pain Expectations
Birds
Pigeons
Falcons
Cardinals
Chemistry and Materials
The chemistry of sleeplessness
Cold, colder and coldest ice
The Buzz about Caffeine
Computers
Nonstop Robot
Supersonic Splash
Getting in Touch with Touch
Dinosaurs and Fossils
Mini T. rex
The man who rocked biology to its core
A Rainforest Trapped in Amber
E Learning Jamaica
Results of GSAT are in schools this week
E Learning in Jamaica WIN PRIZES and try our Fun Animated Games
2014 GSAT Results for Jamaican Kids
Earth
Deep Drilling at Sea
Earth from the inside out
Getting the dirt on carbon
Environment
Giant snakes invading North America
Flu river
Hazy with a Chance of Sunshine
Finding the Past
Unearthing Ancient Astronomy
Untangling Human Origins
Writing on eggshells
Fish
Whale Sharks
Sharks
White Tip Sharks
Food and Nutrition
In Search of the Perfect French Fry
Sponges' secret weapon
How Super Are Superfruits?
GSAT English Rules
Who vs. That vs. Which
Whoever vs. Whomever
Subject and Verb Agreement
GSAT Exam Preparation Jamaica
How are students placed after passing the GSAT exam
The Annual GSAT Scholarships
Results of GSAT are in schools this week
GSAT Exams Jamaica Scholarships
Results of GSAT are in schools this week
GSAT stars reap scholarship glory
Access denied - Disabled boy aces GSAT
GSAT Mathematics
Monkeys Count
42,000 students will sit for the GSAT Exam in two weeks
Secrets of an Ancient Computer
Human Body
Sun Screen
Music in the Brain
Prime Time for Broken Bones
Invertebrates
Centipedes
Leeches
Mussels
Mammals
Hamsters
Ponies
Tasmanian Devil
Parents
How children learn
The Surprising Meaning and Benefits of Nursery Rhymes
Raise a Lifelong Reader by Reading Aloud
Physics
Project Music
Spin, Splat, and Scramble
Echoes of a Stretched Egg
Plants
Plants Travel Wind Highways
Underwater Jungles
Nature's Alphabet
Reptiles
Pythons
Chameleons
Sea Turtles
Space and Astronomy
Older Stars, New Age for the Universe
Melting Snow on Mars
Unveiling Titan
Technology and Engineering
A Micro-Dose of Your Own Medicine
Are Propellers Fin-ished?
Weaving with Light
The Parts of Speech
Adjectives and Adverbs
Problems with Prepositions
What is a Noun
Transportation
How to Fly Like a Bat
Where rivers run uphill
Seen on the Science Fair Scene
Weather
Watering the Air
A Change in Climate
Polar Ice Feels the Heat
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™