Pesticide Turns Male Frogs Into Females

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A commonly used pesticide known as atrazine can turn male frogs into females that are successfully able to reproduce, a new study finds.While previous work has shown atrazine can cause sexual abnormalities in frogs, such as hermaphroditism (having both male and female sex organs), this study is the first to find that atrazine’s effects are long-lasting and can influence reproduction in amphibians.

The results suggest that atrazine, which is a weed killer used primarily on corn crops, could have potentially harmful effects on populations of amphibians, animals that are already experiencing a global decline, said study author Tyrone B. Hayes of the University of California, Berkeley. Atrazine is banned in Europe.And since atrazine interferes with the production of the sex hormone estrogen, present in people and frogs, the findings could have implications for humans as well. “If you have problems in amphibians, you can anticipate problems in other animals,” Hayes said.
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Zoo Giraffe Enjoys Regular Pedicures

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Standing out from the crowd has taken on a whole new meaning for Thorn, the tallest giraffe at England’s Chester zoo. Thorn gets daily pedicures from zookeepers, and unlike other giraffes that take anesthetics for similar treatment, he goes into each session wide awake.So how does this Rothschild giraffe stay unruffled during the procedure? Zookeepers use a pioneering training technique that involves voice commands and food rewards to get Thorn to cooperate. Over the past 12 months since they first started the process, Thorn has learned to stay put for 10 to 15 minutes at a time.

“At first it took some getting used to,” keeper Lizzie Bowen says of Thorn’s reaction to the pedicures. “It took us six months before we trained him to rest his foot long enough for us to be able to rasp his foot.” But Thorn grew increasingly comfortable with the presence of zoo staff. “He remains calm around them. It has become part of his routine now,”
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The Lessons In Courtship We Can Learn From Animal

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LOVE IS A DRUG

Most male mice are happy with just a short moment of passion – a quick knee-trembler behind the skirting board with a partner, and then he’s off. But a male Californian Mouse is the opposite: he seems a perfect mouse-husband who stays in to help groom and feed his mousewife, bringing her water, doing the housework and helping to look after their babies.Proof that he’s fallen head over paws in love? No, simply that the clever female has drugged him.She produces hormones in her urine that he finds intoxicating. Something in his brain is triggered by the scent, and he becomes her slave, working to exhaustion.Sound familiar? It should do. Because love is a drug for humans, too. When we fall in love, our brains swim with opioids – a natural intoxicant from the same class of chemical as heroin – and similarly addictive
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Turns Out Mary The Tortoise Is Actually A Male

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Three Aldabra tortoises have lived at the Cleveland Metroparks Zoo for the past 50 years. Their names are Tom, Tim and Mary — well, in Mary’s case, was. During a spontaneous physical exam in early November, Mary, whose short tail, domed upper shell and small size had led zoo staff to believe she was a female, showed an internal reproductive organ that “left no question of his manhood,” according to the zoo’s blog. Turned out that Mary the female Aldabra tortoise is a guy.

“Obviously, we were very surprised by this,” Jeff Hall, the zoo’s general curator, tells Ezquara.com. “But stranger things have happened in the world, so it’s not unbelievable, but it was a surprise.”

Mary’s physical appearance not only appeared to have the sexual characteristics of a female, but Mary also never mounted the other tortoises — or displayed any desire to. Because this tortoise does not usually breed in captivity or in the northern hemisphere, breeding was never a priority for the zoo.
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Rhea Chicks Burrow In Their Father's Feathers

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Three of the four new rhea chicks at the Smithsonian’s National Zoo nest in the feathers of their father. The chicks hatched on Apr. 20 and were the first rhea chicks to hatch at the National Zoo in 30 years. Dedicated fathers, it is the male rhea who incubates the eggs and protects the chicks after they hatch. The Zoo is now home to a total of seven rheas: a male, two females, and the four new chicks.

Male Bird at National Zoological Park Has Special Reason to Celebrate Father’s Day How will the only male rhea at the Smithsonian’s National Zoo spend Father’s Day? He will spend it much like he has spent the past eight weeks: as a proud papa nurturing and caring for his four chicks that hatched April 20. This is the first time in some 30 years that rhea chicks have hatched at the Zoo.

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Rhea Chicks Burrow In Their Father's Feathers

1

Three of the four new rhea chicks at the Smithsonian’s National Zoo nest in the feathers of their father. The chicks hatched on Apr. 20 and were the first rhea chicks to hatch at the National Zoo in 30 years. Dedicated fathers, it is the male rhea who incubates the eggs and protects the chicks after they hatch. The Zoo is now home to a total of seven rheas: a male, two females, and the four new chicks.

Male Bird at National Zoological Park Has Special Reason to Celebrate Father’s Day How will the only male rhea at the Smithsonian’s National Zoo spend Father’s Day? He will spend it much like he has spent the past eight weeks: as a proud papa nurturing and caring for his four chicks that hatched April 20. This is the first time in some 30 years that rhea chicks have hatched at the Zoo.

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DNA Mechanism That Prevents Two Species From Reproducing Discovered

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When two populations of a species become geographically isolated from each other, their genes
diverge from one another over time.

Cornell researchers have discovered a genetic mechanism in fruit flies that prevents two closely related species from reproducing, a finding that offers clues to how species evolve.
Eventually, when a male from one group mates with a female from the other group, the offspring will die or be born sterile, as crosses between horses and donkeys produce sterile mules. At this point, they have become two distinct species.
Now, Cornell researchers report in the October issue of Public Library of Science Biology (Vol. 7, No. 10) that rapidly evolving “junk” DNA may create incompatibilities between two related species, preventing them from reproducing. In this case, the researchers studied crosses between closely related fruit flies, Drosophila melanogaster and D. simulans. Nearly 100 years ago, scientists discovered that when male D. melanogasters mate with female D. simulans, normal males survive, but the female embryos die.
“It has remained an unsolved problem,” said Patrick Ferree, the paper’s lead author and a postdoctoral researcher in the lab of co-author Daniel Barbash, an assistant professor of molecular biology and genetics. “The question is, what are the elements that are killing these female hybrids and how are they doing that?”
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