Agriculture
Chicken Eggs as Drug Factories
Getting the dirt on carbon
Growing Healthier Tomato Plants
Amphibians
Tree Frogs
Frogs and Toads
Newts
Animals
Baboons Listen for Who's Tops
Roboroach and Company
Sea Giants and Island Pygmies
Behavior
Homework blues
The Snappy Lingo of Instant Messages
A Global Warming Flap
Birds
Pheasants
Woodpecker
Penguins
Chemistry and Materials
Fog Buster
Cooking Up Superhard Diamonds
Getting the dirt on carbon
Computers
Two monkeys see a more colorful world
Middle school science adventures
Electronic Paper Turns a Page
Dinosaurs and Fossils
Did Dinosaurs Do Handstands?
Dino Flesh from Fossil Bone
A Rainforest Trapped in Amber
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
Rodent Rubbish as an Ice-Age Thermometer
A Global Warming Flap
Digging into a Tsunami Disaster
Environment
A Newspaper's Hidden Cost
Missing Tigers in India
Acid Snails
Finding the Past
Sahara Cemetery
An Ancient Childhood
A Human Migration Fueled by Dung?
Fish
A Grim Future for Some Killer Whales
White Tip Sharks
Hammerhead Sharks
Food and Nutrition
Turning to Sweets, Fats to Calm the Brain
Sponges' secret weapon
Allergies: From Bee Stings to Peanuts
GSAT English Rules
Subject and Verb Agreement
Who vs. Whom
Finding Subjects and Verbs
GSAT Exam Preparation Jamaica
GSAT Exam Preparation
10 Common Mistakes When Preparing for the GSAT Math Test
Preparing for the GSAT Exam
GSAT Exams Jamaica Scholarships
Access denied - Disabled boy aces GSAT
GSAT Practice Papers | GSAT Mathematics | Maths
42,000 students will sit for the GSAT Exam in two weeks
GSAT Mathematics
Math Naturals
Setting a Prime Number Record
42,000 students will sit for the GSAT Exam in two weeks
Human Body
A Fix for Injured Knees
Flu Patrol
Cell Phone Tattlers
Invertebrates
Arachnids
Dust Mites
Giant Clam
Mammals
Miscellaneous Mammals
Mongooses
Hoofed Mammals
Parents
Expert report highlights the importance to parents of reading to children!
What Not to Say to Emerging Readers
The Surprising Meaning and Benefits of Nursery Rhymes
Physics
One ring around them all
The Mirror Universe of Antimatter
Hold on to your stars, ladies and gentlemen
Plants
A Change in Leaf Color
Springing forward
Hungry bug seeks hot meal
Reptiles
Crocodiles
Rattlesnakes
Pythons
Space and Astronomy
Cousin Earth
Wrong-way planets do gymnastics
Saturn's New Moons
Technology and Engineering
Dancing with Robots
Space Umbrellas to Shield Earth
Algae Motors
The Parts of Speech
What is a Verb?
Countable and Uncountable Nouns
Adjectives and Adverbs
Transportation
Flying the Hyper Skies
Ready, unplug, drive
Charged cars that would charge
Weather
A Dire Shortage of Water
Either Martians or Mars has gas
Polar Ice Feels the Heat
Add your Article

Rodents

Found across almost the entire globe, rodents have learned to thrive in deserts, grasslands, and especially around human settlements, where some species (like mice and rats) have become common pests. Humans keep some rodents as pets, but even wild ones (such as squirrels and chipmunks) have learned to live in harmony with us in the city and suburbs. Although usually thought of as small -- with the more common species being small enough to hold in your hands -- there are others, like the Capybara, which can grow to the size of small dog. In terms of number of species (though not necessarily in terms of number of organisms–population–or biomass) rodents make up the largest order of mammals, with over 40 percent of mammalian species belonging to the order. There are between 2000 and 3000 species of rodents, which are found in vast numbers on all continents except Antarctica (they are the only placental order other than bats, Chiroptera, to reach Australia without human introduction), most islands, and in all habitats except for oceans. Most rodents are small; the tiny African pygmy mouse is only 6 cm in length and 7 grams in weight. On the other hand, the capybara can weigh up to 45 kg (100 pounds) and the extinct Phoberomys pattersoni is believed to have weighed 700 kg. Rodents have two incisors in the upper as well as in the lower jaw which grow continuously and must be kept worn down by gnawing; this is the origin of the name, from the Latin rodere, to gnaw, and dent, tooth. These teeth are used for cutting wood, biting through the skin of fruit, or for defense. The teeth have enamel on the outside and exposed dentine on the inside, so they self-sharpen during gnawing. Rodents lack canines, and have a space between their incisors and premolars. Nearly all rodents feed on plants, seeds in particular, but there are a few exceptions which eat insects or even fish. Rodents are important in many ecosystems because they reproduce rapidly, and can function as food sources for predators, mechanisms for seed dispersal, and as disease vectors. Humans use rodents as a source of fur, as model organisms in animal testing, for food, and even in detecting landmines. Members of non-rodent orders such as Chiroptera (bats), Scandentia (treeshrews), Insectivora (moles, shrews and hedgehogs), Lagomorpha (hares, rabbits and pikas) and mustelid carnivores such as weasels and mink are sometimes confused for rodents. The fossil record of rodents began after the extinction of the dinosaurs 65 million years ago. By the end of the Eocene epoch, beavers and squirrels appeared in the fossil record. They originated in Laurasia, the joined continents of North America, Europe, and Asia. Some species colonized Africa, giving rise to the earliest hystricognaths. From there they rafted to South America, an isolated continent during the Oligocene and Miocene epochs. By the Miocene, Africa collided with Asia, allowing rodents such as porcupines to spread into Eurasia. During the Pliocene, rodent fossils appeared in Australia. Even though marsupials are the prominent mammals in Australia, rodents make up almost 25% of the mammals on the continent. Meanwhile, the Americas became joined and some rodents expanded into new territory; mice headed south and porcupines headed north.

Rodents
Rodents








Designed and Powered by HBJamaica.com™