Agriculture
Growing Healthier Tomato Plants
Where Have All the Bees Gone?
Got Milk? How?
Amphibians
Salamanders and Newts
Frogs and Toads
Salamanders
Animals
Sleep Affects a Bird's Singing
Sea Giants and Island Pygmies
Who's Knocking?
Behavior
The Electric Brain
Fish needs see-through head
Night of the living ants
Birds
Falcons
Dodos
Owls
Chemistry and Materials
Salt secrets
Hair Detectives
The Taste of Bubbles
Computers
Secrets of an Ancient Computer
Programming with Alice
Fingerprint Evidence
Dinosaurs and Fossils
Meet the new dinos
The man who rocked biology to its core
Hunting by Sucking, Long Ago
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
In Antarctica watch the heat (and your step)
Watering the Air
Slower Growth, Greater Warmth
Environment
Pumping Up Poison Ivy
A Change in Climate
Blooming Jellies
Finding the Past
Sahara Cemetery
Digging Up Stone Age Art
Decoding a Beverage Jar
Fish
Electric Ray
Dogfish
Eels
Food and Nutrition
The Essence of Celery
Eat Out, Eat Smart
Recipe for Health
GSAT English Rules
Who vs. That vs. Which
Adjectives and Adverbs
Order of Adjectives
GSAT Exam Preparation Jamaica
How are students placed after passing the GSAT exam
2014 GSAT Results for Jamaican Kids
The Annual GSAT Scholarships
GSAT Exams Jamaica Scholarships
GSAT Practice Papers | GSAT Mathematics | Maths
2014 GSAT Results for Jamaican Kids
42,000 students will sit for the GSAT Exam in two weeks
GSAT Mathematics
Prime Time for Cicadas
E Learning in Jamaica WIN PRIZES and try our Fun Animated Games
Math is a real brain bender
Human Body
Workouts: Does Stretching Help?
A New Touch
Disease Detectives
Invertebrates
Squid
Fleas
Arachnids
Mammals
Wombats
Wildcats
Hamsters
Parents
Expert report highlights the importance to parents of reading to children!
Choosing a Preschool: What to Consider
How children learn
Physics
Road Bumps
Einstein's Skateboard
Hold on to your stars, ladies and gentlemen
Plants
The algae invasion
Hungry bug seeks hot meal
Pumping Up Poison Ivy
Reptiles
Anacondas
Turtles
Copperhead Snakes
Space and Astronomy
Asteroid Moons
Melting Snow on Mars
A Smashing Display
Technology and Engineering
Drawing Energy out of Wastewater
Morphing a Wing to Save Fuel
Beyond Bar Codes
The Parts of Speech
What is a Preposition?
Problems with Prepositions
Countable and Uncountable Nouns
Transportation
Are Propellers Fin-ished?
Flying the Hyper Skies
Morphing a Wing to Save Fuel
Weather
Polar Ice Feels the Heat
A Change in Climate
Catching Some Rays
Add your Article

When frog gender flips

Several months ago, a California college student working at a university laboratory checked up on a group of frogs and saw some unusual behavior. Some of the frogs were acting like females — which was unusual, since at the beginning of the experiment all of the frogs were males. The student, Ngoc Mai Nguyen, says she told her boss, biologist Tyrone Hayes, “‘I don’t know what’s going on, but I don’t think this is normal.'” Nguyen, a student at the University of California, Berkeley, was working in Hayes’ laboratory. Hayes told Nguyen to keep watching — and write down what she saw each day. Nguyen knew all the frogs had started out as males. She didn’t know, however, what Hayes knew: that there was something in the water of the frog tank. That something was a popular weed killer called atrazine, and since birth the frogs had been raised in water that contained the chemical. Hayes says the experiments in his lab show that 30 percent of the male frogs that grew up in water with atrazine started to behave like females, and even send out chemical signals to attract other males.Laboratory experiments are not the only places where frogs may run into atrazine. The chemical is used as a weed killer, so it can pollute surface water downstream of the crops where it is used. In these rivers and streams, the concentration of atrazine can reach 2.5 parts per billion — the same concentration Hayes tested in his laboratory. This similarity suggests that male frogs may be turning into females in their natural habitats. The Environmental Protection Agency, or EPA, is a government organization responsible for protecting human health and the environment. The EPA defines what concentrations of certain chemicals are allowed in U.S. waterways, and the EPA has determined that up to 3 parts per billion — well above the concentration that turns male frogs into females — of atrazine is safe. If Hayes is right, even the EPA definition of a safe concentration is actually not safe for frogs. Hayes and his team have also showed that it’s not just the frogs’ behavior that changes after exposure to atrazine. Males raised in water containing atrazine had low levels of testosterone and did not try to attract females. But that’s not all: Out of 40 frogs raised in water containing atrazine, four had high levels of estrogen — a female hormone (that’s four out of 40 frogs, or one in 10). Hayes and his team dissected two of the frogs and found female reproductive organs. The other two transgender frogs were introduced to healthy males and mated with those males, producing baby male frogs. Other scientists have looked at Hayes’ work and carried out similar experiments — with similar results. Plus, researchers who study other animals have observed that atrazine affects those animals’ hormones. At least one scientist, Tim Pastoor, says Hayes has made mistakes in his study and that atrazine is safe. Pastoor is a scientist with Syngenta Crop Protection, a company that makes and sells atrazine. In an email to Science News, Pastoor wrote that Hayes’ new experiments don’t lead to the same results as Hayes’ earlier studies. “Either his current study discredits his previous work, or his previous work discredits this study,” Pastoor wrote. It’s important to know how atrazine affects the animal population. Any chemical that can change the reproductive patterns of an animal threatens that species’ survival.

When frog gender flips
When frog gender flips








Designed and Powered by HBJamaica.com™