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View Full Version : Pollutants can change male frogs into female frogs.


check two
02-27-2007, 03:42 PM
PARIS (AFP) - Frogs that started life as male tadpoles were changed in an experiment into females by estrogen-like pollutants similar to those found in the environment, according to a new study.

The results may shed light on at least one reason that up to a third of frog species around the world are threatened with extinction, suggests the study, set to appear in the journal Environmental Toxicology and Chemistry in May.

In a laboratory at Uppsala University in Sweden, two species of frogs were exposed to levels of estrogen similar to those detected in natural bodies of water in Europe, the United States and Canada.

The results were startling: whereas the percentage of females in two control groups was under 50 percent -- not unusual among frogs -- the sex ratio in three pairs of groups maturing in water dosed with different levels of estrogen were significantly skewed.

Even tadpoles exposed to the weakest concentration of the hormone were, in one of two groups, twice as likely to become females.

The population of the two groups receiving the heaviest dose of estrogen became 95 percent female in one case, and 100 percent in the other.

"The results are quite alarming," said co-author Cecilia Berg, a research in environmental toxicology. "We see these dramatic changes by exposing the frogs to a single substance. In nature there could be lots of other compounds acting together."

Earlier studies in the United States, Berg explained, linked a similar sex-reversal of Rana pipiens male frogs -- one of the two species used in the experiment -- in the wild to a pesticide that produced estrogen-like compounds.

"Pesticides and other industrial chemicals have the ability to act like estrogen in the body," Berg said. "That is what inspired us to do the experiment," she said referring to her collaborator and lead author of the article, Irina Pettersson, also a researcher at Uppsala.

The other species examined was the European common frog, Rana temporaria.

Some of sex-altered males became fully functioning females, but other had ovaries but no oviducts, making them sterile, Berg explained.

The study does not measure the potential impact of pollutant-driven sex change for frog species, but the implications, said Berg, are disquieting.

"Obviously if all the frogs become female it could have a detrimental effect on the population," she said.

The only immediate remedy, she continued, would be to improve sewage treatment in areas where frogs and other amphibians might be affected to filter out estrogen concentrations coming from contraceptive pills and from industrial pollutants.

news.yahoo.com

Gawd
02-27-2007, 05:42 PM
reptiles have been known to change their sexes and even have offspring without having sex.

this story is just a global warming scheme.

check two
02-27-2007, 05:59 PM
And I guess the fact that about 1/3 of the frog species is facing extinction is just a scheme also?

Gawd
02-27-2007, 06:04 PM
And I guess the fact that about 1/3 of the frog species is facing extinction is just a scheme also?
dinosaurs became extinct without pollution or green house gasses. so yeah who cares, species die out and new one are discovered.


jump on the global warming dick.

Sexy Jasper
02-27-2007, 06:21 PM
I can't wait for global warming to take full effect. I'm impatiently shopping for swimming trunks.

Gawd
02-27-2007, 06:25 PM
i dont wear swimming suits on account of the man boobs and all. i stay clothed with some b ball shorts and a camiseta

check two
02-28-2007, 03:08 PM
dinosaurs became extinct without pollution or green house gasses. so yeah who cares, species die out and new one are discovered.


jump on the global warming dick.

I'm not jumping on the global warming dick. Global warming isn't even mentioned in the article. It's cool that you don't give a damn about the environment and things in it. All you care about is your 20 twinkies a day. But if hippos die off, I'll spill some Ol' E for your memory.

Gawd
02-28-2007, 03:14 PM
I'm not jumping on the global warming dick. Global warming isn't even mentioned in the article. It's cool that you don't give a damn about the environment and things in it. All you care about is your 20 twinkies a day. But if hippos die off, I'll spill some Ol' E for your memory.

why should i give a shit if a species of frog is dieing off? just today an article came out describing how 20 new ocean species have been discovered off indonisia. are you gonna celebrate that shit with some soybean burgers and rice cakes?

species die off and new ones are discovered.

that is the circle of fucking life.

now make another enviornmentalist thread then git mad cuz you do not like my replies. faggit.

check two
02-28-2007, 03:16 PM
Fuck you, ya fat piece of ugly shit. It's a legitimate thread. I can't help it that I don't sit around and eat junk food all day, ya lazy ass bastard. Go fuck Janet Reno, but she'd reject ya.

Gawd
02-28-2007, 03:26 PM
Fuck you, ya fat piece of ugly shit. It's a legitimate thread. I can't help it that I don't sit around and eat junk food all day, ya lazy ass bastard. Go fuck Janet Reno, but she'd reject ya.

oh that was a great contribution to the thread. get backed into a corner did ya? have nothing else to say so you have to throw around baseless insults. damn. i thought we were having a decent convo but whatever. get mad. lawls asshat.

check two
02-28-2007, 03:32 PM
lol, I was having a decent conversation till you started spewing nonsense.

Gawd
02-28-2007, 03:34 PM
dinosaurs became extinct without pollution or green house gasses. so yeah who cares, species die out and new one are discovered.


jump on the global warming dick.

hhmmm this nonsense?

yeah k dood.

LHX
02-28-2007, 03:35 PM
why should i give a shit if a species of frog is dieing off? just today an article came out describing how 20 new ocean species have been discovered off indonisia. are you gonna celebrate that shit with some soybean burgers and rice cakes?

species die off and new ones are discovered.

that is the circle of fucking life.

now make another enviornmentalist thread then git mad cuz you do not like my replies. faggit.

this = LMFAO

eD is riding the correct pope-mobile



plus

i HATE soy products

Civilison scared me off that shit

check two
02-28-2007, 03:36 PM
Global warming had nothing to do with the thread, so why even bring that up. And just because I care about a species other than my own, and my surroundings, I'm automatically labeled an environmentalist by ya.

Pollution=big business.

Gawd
02-28-2007, 03:39 PM
Global warming had nothing to do with the thread, so why even bring that up. And just because I care about a species other than my own, and my surroundings, I'm automatically labeled an environmentalist by ya.

Pollution=big business.


Just because i dont give a shit about some frogs doesnt mean im a enviornment hating neo con. dont like being labeled? so why label other ppl.....lawls.

bizzlez
02-28-2007, 06:28 PM
I think I heard my brother say this one day, didn't know it was true

Jet Set
03-01-2007, 02:50 AM
Frogs and such animals are a big meter to which the environment is polluted. They live in both the land and the water. That's what makes it different. Since Jurassic Park it is known that reptiles could change their sex.

Now it maybe just all fine that 20 new species were discovered, but why are they now discovered? Because they just maybe don't have a huge part in the cricle of life. Their role isn't clear.