Flush-Free Fertilizer
Making the most of a meal
Microbes at the Gas Pump
Helping the Cause of Macaws
Cannibal Crickets
Math Naturals
Surprise Visitor
Backyard Birds
Chemistry and Materials
Music of the Future
Sugary Survival Skill
Small but WISE
A Classroom of the Mind
New eyes to scan the skies
The Book of Life
Dinosaurs and Fossils
Watery Fate for Nature's Gliders
Dino Takeout for Mammals
Fossil Fly from Antarctica
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
Farms sprout in cities
Quick Quake Alerts
What is groundwater
A Newspaper's Hidden Cost
Shrimpy Invaders
Whale Watch
Finding the Past
Of Lice and Old Clothes
Digging Up Stone Age Art
Sahara Cemetery
Electric Eel
A Grim Future for Some Killer Whales
Food and Nutrition
Chew for Health
Allergies: From Bee Stings to Peanuts
The Essence of Celery
GSAT English Rules
Who vs. Whom
Whoever vs. Whomever
Who vs. That vs. Which
GSAT Exam Preparation Jamaica
2014 GSAT Results for Jamaican Kids
Tarrant High overcoming the odds
E Learning in Jamaica WIN PRIZES and try our Fun Animated Games
GSAT Exams Jamaica Scholarships
Results of GSAT are in schools this week
GSAT stars reap scholarship glory
42,000 students will sit for the GSAT Exam in two weeks
GSAT Mathematics
GSAT Practice Papers | GSAT Mathematics | Maths
Monkeys Count
Detecting True Art
Human Body
Running with Sneaker Science
What the appendix is good for
Sun Screen
Sea Anemones
Praying Mantis
African Wild Dog
What Not to Say to Emerging Readers
Choosing a Preschool: What to Consider
Raise a Lifelong Reader by Reading Aloud
Extra Strings for New Sounds
IceCube Science
Spin, Splat, and Scramble
Stalking Plants by Scent
Plants Travel Wind Highways
Flower family knows its roots
Box Turtles
Snapping Turtles
Space and Astronomy
Catching a Comet's Tail
Ready, Set, Supernova
Dark Galaxy
Technology and Engineering
A Clean Getaway
Dancing with Robots
Roll-Up Computer Monitors to Go
The Parts of Speech
Countable and Uncountable Nouns
Problems with Prepositions
Robots on a Rocky Road
Troubles with Hubble
Where rivers run uphill
Where rivers run uphill
Polar Ice Feels the Heat
The solar system's biggest junkyard
Add your Article

Ancient Heights

You probably know where all the hills are in your neighborhood. Even so, the planet hasn't always had the same lumps. In some places, Earth was even lumpier that it is now. In other places, it was smoother. Over millions of years, entire mountain ranges have come and gone. The landscape is always changing. Now, a geologist from the Field Museum in Chicago says that she has found a new way to figure out how the shape of Earth's surface has changed over time. Her strategy? Leaf peeping. A tree's leaves have tiny holes called stomata. These pores allow the leaves to take in a gas called carbon dioxide, which the tree needs in order to survive. With this fact in mind, geologist Jennifer McElwain collected leaves from living California black oak. These trees grow in a wide range of altitudes, from sea level all the way up to 2,500 meters (8,200 feet). McElwain used a microscope to count how many stomata were inside a given area of each leaf. She found that the leaves had more stomata at higher altitudes. Then, she came up with an equation that links stomata numbers and elevation. The black oak has been around for at least 24 million years. So, scientists can now count stomata on fossilized leaves to figure out how high the trees were when they lived, McElwain says. By comparing this altitude with the altitude at which the fossils were collected, the researchers can measure any changes in elevation that had occurred. The new method should be more accurate than previous methods, McElwain says. Next, she wants to come up with equations for other tree species. Someday, she says, her research may help scientists answer a major question in geology: When did the Himalayas in Asia rise?E. Sohn

Ancient Heights
Ancient Heights

Designed and Powered by™