Agriculture
Fast-flying fungal spores
Earth-Friendly Fabrics
Cleaning Up Fish Farms
Amphibians
Salamanders
Frogs and Toads
Salamanders and Newts
Animals
The Littlest Lemurs
A Microbe Nanny for Young Wasps
Koalas, Up Close and Personal
Behavior
Bringing fish back up to size
Primate Memory Showdown
Mind-reading Machine
Birds
Robins
Birds We Eat
Emus
Chemistry and Materials
Meteorites may have sparked life on Earth
Scientist Profile: Wally Gilbert
Boosting Fuel Cells
Computers
Galaxies far, far, far away
The science of disappearing
Music of the Future
Dinosaurs and Fossils
The man who rocked biology to its core
Supersight for a Dino King
Have shell, will travel
E Learning Jamaica
Results of GSAT are in schools this week
2014 GSAT Results for Jamaican Kids
E Learning in Jamaica WIN PRIZES and try our Fun Animated Games
Earth
Plastic-munching microbes
A Volcano's Deadly Ash
A Volcano Wakes Up
Environment
City Trees Beat Country Trees
Antarctica warms, which threatens penguins
Island Extinctions
Finding the Past
Of Lice and Old Clothes
Big Woman of the Distant Past
Prehistoric Trips to the Dentist
Fish
Dogfish
Freshwater Fish
Bull Sharks
Food and Nutrition
Food for Life
Symbols from the Stone Age
Eat Out, Eat Smart
GSAT English Rules
Pronouns
Adjectives and Adverbs
Finding Subjects and Verbs
GSAT Exam Preparation Jamaica
GSAT Practice Papers | GSAT Mathematics | Maths
42,000 students will sit for the GSAT Exam in two weeks
GSAT Scholarship
GSAT Exams Jamaica Scholarships
GSAT Practice Papers | GSAT Mathematics | Maths
GSAT stars reap scholarship glory
42,000 students will sit for the GSAT Exam in two weeks
GSAT Mathematics
GSAT Mathematics Quiz, Teaching Math, teaching anxiety
Secrets of an Ancient Computer
Play for Science
Human Body
Opening a Channel for Tasting Salt
Spit Power
Fighting Off Micro-Invader Epidemics
Invertebrates
Cockroaches
Crustaceans
Nautiluses
Mammals
Mule
Wolves
Doberman Pinschers
Parents
Raise a Lifelong Reader by Reading Aloud
What Not to Say to Emerging Readers
How children learn
Physics
One ring around them all
Strange Universe: The Stuff of Darkness
Road Bumps
Plants
A Change in Leaf Color
Springing forward
When Fungi and Algae Marry
Reptiles
Sea Turtles
Turtles
Reptiles
Space and Astronomy
Cool as a Jupiter
Sun Flips Out to Flip-Flop
Killers from Outer Space
Technology and Engineering
Young Scientists Take Flight
Crime Lab
A Clean Getaway
The Parts of Speech
Problems with Prepositions
What is a Noun
Adjectives and Adverbs
Transportation
Flying the Hyper Skies
Tinkering With the Basic Bike
How to Fly Like a Bat
Weather
Where rivers run uphill
Warmest Year on Record
Science loses out when ice caps melt
Add your Article

Battling Mastodons

Mastodons no longer exist, but their fossils provide glimpses of how they once lived. Researchers now say that marks on fossil tusks suggest that male mastodons fought violent battles with each other at a certain time every year of their adult lives. "American mastodons were not just docile herbivores that whiled away their time in forests and meadows," says Daniel C. Fisher, a paleontologist at the University of Michigan in Ann Arbor. "They were very aggressive animals." Mastodons no longer exist, but their fossils provide glimpses of how they once lived. Researchers now say that marks on fossil tusks suggest that male mastodons fought violent battles with each other at a certain time every year of their adult lives. "American mastodons were not just docile herbivores that whiled away their time in forests and meadows," says Daniel C. Fisher, a paleontologist at the University of Michigan in Ann Arbor. "They were very aggressive animals." Mastodons no longer exist, but their fossils provide glimpses of how they once lived. Researchers now say that marks on fossil tusks suggest that male mastodons fought violent battles with each other at a certain time every year of their adult lives. "American mastodons were not just docile herbivores that whiled away their time in forests and meadows," says Daniel C. Fisher, a paleontologist at the University of Michigan in Ann Arbor. "They were very aggressive animals." Mastodons lived in North America between 4 million and 10,000 years ago. In 1999, paleontologists in Hyde Park, N.Y., dug up long, curved mastodon tusks that dated back 11,480 years. When Fisher looked at the undersides of the tusks, he noticed rows of shallow grooves, or pits, that were spaced at regular intervals. Then, he cut a tusk into slices and looked at them under a microscope. A closer look showed that the layer of tooth, called dentin, was damaged in the areas underneath the pits, as well. Like the tusks of elephants, mastodon tusks were made of ivory, and they grew throughout an animal's life. The cells that form new ivory lie at the base of the tusk where dentin meets the hard outer layer of the tooth, called cementum. Based on the position of the grooves and the chemical composition of the tusks, the researchers concluded that the injuries happened between the middle of spring and summer. The damage appeared every year of the animal's life after the age of 20. In battle, a male mastodon would sometimes dip its head down and then swing it back up so that the tips of its tusks would stab the neck or skull of its foe. This type of blow could be fatal to the other guy, but the impact could also jam the attacker's tusks back into their sockets. That jamming, Fisher says, could have caused the odd pattern of scars. A mastodon fossil found in Indiana has similar markings, Fisher says, but the damage appears only after every 2 or 3 years of growth during the mastodon's adult life. People lived alongside mastodons in the area. Fisher suspects that hunting may have reduced the number of males and the number of fights. Fisher's hypothesis makes sense, other scientists say, but questions still remain. Modern elephants, for example, fight with their tusks, but they don't develop the same kind of tusk damage. It'll take a bit more sleuthing to truly understand the lives of the magnificent mastodons.E. Sohn

Battling Mastodons
Battling Mastodons








Designed and Powered by HBJamaica.com™