Monkeys once color-blind can now see the world in full color thanks to gene therapy. The results demonstrate the potential for such methods to eventually cure human vision disorders, from color blindness to possibly other conditions leading to full blindness.

The primate patients, named Dalton and Sam, are two adult, male squirrel monkeys that were red-green color-blind since birth — a condition that similarly affects human males more than females. Five months after researchers injected human genes into the monkeys’ eyes, the duo could see red as if they had always had this ability.

Since human genes were used and the monkeys’ eyes and brains are similar to ours, at least in terms of color vision, the researchers hope the same procedure could work in humans.

“People who are color-blind feel that they are missing out,” said study researcher Jay Neitz, a professor of ophthalmology at the University of Washington, Seattle. “If we could find a way to do this with complete safety in human eyes, as we did with monkeys, I think there would be a lot of people who would want it.”

Karen Horne, 38, says her cat is a genetic impossibility. The cat is male, and boy cats should be unable to inherit multi-colors because they have only one X chromosome in their DNA.

“As a vet I can tell you that it is genetically impossible to get a male cat that is tortoiseshell-colored,” she told Britain’s Telegraph.

“My colleagues and I have 30 years of experience between us and we have never seen anything like this.”

After the eight-week-old kitten was brought to her clinic in Harpenden, Hertfordshire, with three tortoiseshell sisters, Horne set about vaccinating the litter. It was then she discovered that one was male.

She immediately adopted the so-named Eddie into her brood of five cats, four dogs and three children.

“We decided to call him Eddie after Eddie Izzard, the comedian, as he is essentially a boy dressed as a girl.

“I feel like the luckiest vet ever just to see a tortie tom cat, and even luckier to have him live with me. He is a perfect cute little fluffy bundle.”

At first glance, cancer researcher Michael McCulloch’s lab at the Pine Street Foundation in San Rafael, Calif., looks predictably humdrum – a computer, a few beakers and some vials. And yet, if you look a little closer, there’s something downright peculiar about the place. Most notably, the water bowls, leashes and the roll of paper towels used for sopping up slobber.

For the past 10 years, McCulloch, an acupuncturist by training, has been exploring whether the sensitive nose of his furry, four-legged research subjects can detect cancer. And after hearing accounts of canines that reportedly saved the lives of their human owners by sniffing, pawing and barking at their tumors (long before being diagnosed by a physician), he has been grappling with a thought-provoking theory: If a dog can do that spontaneously, that suggests they can be trained to do it.

The idea isn’t as far-fetched as it sounds, insists Dr. J. Leonard Lichtenfeld, the American Cancer Society’s deputy chief medical officer. “An enormous amount of research is being done to find those proteins present in small quantities in the bloodstream that may signal cancer,” Says Lichtenfeld. “That a dog could smell these is definitely within the realm of possibility.”

Female domestic cats tend to preferentially use their right front paw while male cats more often rely upon their left front paw, according to a new study that suggests the sex of a cat determines how its brain will be wired.

The findings also add to a growing body of evidence that male animals tend to be left-handed, or in this case left-pawed, more often than females. While 90 percent of all humans are right-handed, of the remaining southpaws, more tend to be men.

The differences are even clearer among cats.

“Our results suggest that there are two distinct populations of paw preference in the cat that cluster very strongly around the animals’ sex,” Deborah Wells, who led the study, told Discovery News.

Wells, a senior lecturer at Queen’s University Belfast School of Psychology, and co-author Sarah Millsopp examined the paw use of 42 domestic cats. Each cat repeatedly completed three play-like tasks while at home with their owners.

For the first task, the researchers placed a bit of tuna at the bottom of an otherwise empty, narrow-mouthed jar. They then observed how the cats attempted to extract the food treat.

Task two involved a fabric mouse on a string that was suspended above each cat’s head. The paw that was first used to reach for the toy was recorded.

Trying to figure out what your dog is barking about? Maybe you should ask an infant to translate. A new study conducted by researchers at Brigham Young University says that 6-month-olds can understand the meaning of a dog bark.

In the experiment, which was led by BYU psychology professor Ross Flom, the babies were presented with two pictures, one of a dog in friendly “smiling” stance, the other a more aggressive snarl. Then, the researchers played two audio clips, one that sounded like a friendly dog, the other an aggressive dog bark. They found that the 6-month-olds spent the majority of their time staring at the correct picture that corresponded with the appropriate sound.

“It shows that kids have a broad-based ability to discriminate emotion or affect very early in development,” Said Flom. “What young infants do when they hear an auditory cue, like a bark, they will look proportionately longer to the face that goes with what they’re hearing. So when they hear the aggressive bark, they look longer to the aggressive face. When they hear the non-aggressive bark they look longer to the non-aggressive face.”

Flom, who says they chose dogs for the study because of their high ability to communicate, found that the older the infant (they tested 32 at ages 6 months, 12 months, 18 months and 24 months) the less likely they’d match the dog bark with the correct picture. All the babies used in the study had a dog living in their home.

Turns out the 6-month-olds were more attuned to the dog barks than the adults they tested. “The adults tended to treat all barks as aggressive and they kind of wanted to compare bark A with bark B. The 6-month-olds didn’t have that problem,” says Flom, who — along with BYU students Dan Hyde and Heather Whipple Stephenson —reported the findings in the journal Developmental Psychology.

Dogs possess a 2-year-old child’s capacity to understand human pointing gestures, with dogs requiring next to zero learning time to figure out the visual communication, according to two recent studies.

The comparison with kids doesn’t end there. Due to domestication, dogs appear to be predisposed to read other human visual signals, including head-turning and gazing.

Pet owners often use baby talk, scientifically known as “motherese,” with both children and dogs, allowing canines and kids to receive similar social stimulation.

Since chimpanzees and other primates often flunk pointing gesture tests, the studies suggest dogs may understand humans better than even our closest living animal relatives do.

“The human pointing gesture is cooperative in its nature,” Gabriella Lakatos told Discovery News. Lakatos, a researcher in the Department of Ethology at Eotvos University, led the first study, published in the current issue of Animal Cognition.

She explained that other recent studies suggest chimpanzees “might have difficulties with comprehending situations based on cooperation,” mentioning “the observation that chimpanzees do not actively share food.” Dogs, on the other hand, often eagerly cooperate.

For her study on dogs and kids, Lakatos and her colleagues used a combination of finger-, elbow-, leg- and knee-pointing gestures to help dogs locate hidden food and, for children, a favorite toy.

Two-year-olds and dogs understood everything except knee-pointing and when the experimenter’s index finger pointed in a different direction than the protruding arm. For example, they were confused when the individual raised an arm in a certain direction, but used her finger to point the other way.

Human 3-year-olds, on the other hand, aced all of the tests.

Lakatos said that “in human children between the age of two and three years, important changes take place that go beyond the capacities of dogs.” Many of these changes have to do with development of language skills.

“The ability to generalize in children makes the precision of gesturing by the adult less important,” she added. “Children may have a more complex ability to realize the intention behind the pointing gesture.”

When gesturing to a dog or child under 3, it’s therefore best not to fidget or otherwise move in confusing ways.

“Our results show that dogs can understand the pointing gesture if a body part protrudes from the body silhouette,” Lakatos said.

Scientists in New Jersey are describing discovery and successful tests of the first once-a-month pill for controlling both fleas and ticks in dogs and cats

Peter Meinke and colleagues at Merck Research Laboratories note the need for better ways of controlling fleas and ticks, driven in part by increases in pet ownership. Estimates suggest that there were 71 million pet dogs and 81 million pet cats in the United States alone in 2007 — up from 61 million and 70 million in 2001.

Although many powders, sprays and other topical agents are on the market, many pet owners prefer the convenience of pills. Products given orally can reach more parts of an animal’s body, do not wash off in rain or bath water, and don’t transfer from pets to people. At least one existing pill fights fleas in pets, but does not appear effective for ticks.

In tests on fleas and ticks in dogs and cats, a single dose of the new pill was 100 percent effective in protecting against both fleas and ticks for a month. There were no signs of toxic effects on the animals. Scientists obtained the flea and tick fighter from a substance first found in a fungus that “has the potential to usher in a new era in the treatment of ecoparasitic [ticks and fleas, for instance] infestations in companion animals.”

What happens if you tickle a gorilla? According to a new study, apes laugh!

By tickling young gorillas, chimpanzees, bonobos, and orangutans, researchers say they learned that all great apes laugh.

Primatologist and psychologist Marina Davila Ross led a team that tickled the necks, feet, palms, and armpits of infant and juvenile apes as well as human babies. The team recorded more than 800 of the resulting giggles.

However, one mystery remains: What purpose does ape laughter serve?

Davila Ross says, “I’m very keen on learning how laughter is being used among great apes as compared to humans.”

Scientists have shown that transgenic monkeys can pass a newly acquired gene along to their offspring, a “milestone” for creating animals with versions of human diseases for medical research.

While researchers have long created transgenic mice and other animals by giving them extra genetic material, monkeys offer a promising avenue for medical studies because of their similarity to humans.

Researchers have added genes to rhesus macaques before, but the new work with marmosets is the first to document that monkeys can pass an inserted gene along to future generations. That’s important because it opens the door to creating colonies of such “transgenic” monkeys by breeding, which would be far simpler than the cumbersome process of making each animal from scratch by inserting genes into embryos.

The work is reported in Thursday’s issue of the journal Nature by scientists at the Central Institute for Experimental Animals in Kawasaki, Japan, and elsewhere in that country.

The researchers plan to use transgenic marmosets to study such conditions as Parkinson’s disease and Lou Gehrig’s disease, or ALS, a statement from the institute said.

Anthony Chan of the Emory University School of Medicine in Atlanta said the result boosts his confidence that his transgenic macaques will also pass along their added genes to offspring, once they become old enough to reproduce.