Cause of bird behavior dramatized in Hitchcock’s ‘The Birds’ was food poisoning, scientists claim

USA Today reports:

A final mystery surrounding the work of film legend Alfred Hitchcock— what triggered the crazed bird flocks that helped inspire his 1963 thriller The Birds— appears solved by scientists.

Dying and disoriented seabirds rammed themselves into homes across California’s Monterey Bay in the summer of 1961, sparking a long-standing mystery about the cause among marine biologists. The avian incidents sparked local visitor Hitchcock’s interest, along with a story about spooky bird behavior by British writer Daphne du Maurier.

“I am pretty convinced that the birds were poisoned,” says ocean environmentalist Sibel Bargu of Louisiana State University in Baton Rouge. She led a team finding that naturally occurring toxins appear to have been the culprit.

Call it the Case of the Poisoned Plankton. Looking at the stomach contents of turtles and seabirds gathered in 1961 Monterey Bay ship surveys, Bargu and colleagues have now found toxin-making algae were present in 79% of the plankton that the creatures ate. In particular, the team finds in the current Nature Geoscience journal that the leading toxin inside the plankton was a nerve-damaging acid, which causes confusion, seizures and death in birds.

Researchers identify blood-borne substances that cause aging in lab mice

Medical Xpress reports:

In a study to be published Sept. 1 in Nature, Stanford University School of Medicine scientists have found substances in the blood of old mice that makes young brains act older. These substances, whose levels rise with increasing age, appear to inhibit the brain’s ability to produce new nerve cells critical to memory and learning.

The findings raise the question of whether it might be possible to shield the brain from aging by eliminating or mitigating the effects of these apparently detrimental blood-borne substances, or perhaps by identifying other blood-borne substances that exert rejuvenating effects on the brain but whose levels decline with age…

The Nature article is available here (free preview, subscription required for full paper).

Brazilian monkeys develop new method for ‘fishing’ termites

Discovery News reports:

Wild blonde capuchin [monkeys] have invented a new and tool-conserving method to fish for termites, researchers have just discovered.

The technique, reported in the latest Royal Society Biology Letters, has never been documented before for primates, including humans. In fact, people who recently tried out the new five-step termite fishing method found that it worked better than anything else at retrieving the nutritious, yet pesky, insects, which some human cultures eat too.

The psychology of staring contests

MSNBC reports:

A new study suggests that we may engage in staring contests without even thinking about it, especially if we’re people who like to run things. “The initiation of the staredown is reflexive for dominant people,” says study lead author David Terburg, a psychology researcher at Utrecht University in The Netherlands.

The staredown, it seems, is an automatic part of a controlling person’s human-relations toolkit. The bossier you are, the more likely you’ll turn to an encounter into a confrontation without even knowing it.

Scientists find monkeys show self-doubt behavior similar to humans

The BBC reports:

Monkeys trained to play computer games have helped to show that it is not just humans that feel self-doubt and uncertainty, a study says.

US-based scientists found that macaques will “pass” rather than risk choosing the wrong answer in a brainteaser task.

Awareness of our own thinking was believed to be a uniquely human trait.

But the study, presented at the AAAS meeting in Washington DC, suggests that our more primitive primate relatives are capable of such self-awareness.

Inside the canine mind

CNN reports:

Duke University’s Canine Cognition Center in Durham, North Carolina, is one of the few labs in the country focused on how dogs think.

“We’re excited about describing the psychology of our dogs,” says professor Brian Hare, the lab’s director. “Different dogs solve different problems differently. And what we want to understand is: What is it that either makes dogs remarkable as a species or what is it that constrains the ability of dogs to solve problems?”

Hare has been analyzing our four-legged friends for about 15 years. He says dogs have figured out how to read human behavior and human gestures better than any other species has, even chimpanzees.

“The way they think about their world is that people are superimportant and they can solve almost any problem if they rely on people,” says Hare.

New field of ‘optogenetics’ offers new insights into brain function

Wired reports on the new field of optogentics. This research takes light-sensitive plant cells and implants them in animals, allowing light to activate specific neurons in a way not previously possible.

Right ear more responsive to requests than left ear, study finds

Wired reports:

You’re in a loud and sweaty Italian dance club when a woman approaches you. To be heard over the techno, she leans in close and yells into your ear, “Hai una sigaretta?”

If she spoke into your right ear, you would be twice as likely to give her a cigarette than if she asked by your left ear, according to a new study that employed this methodology in the clubs of Pescara, Italy. Of 88 clubbers who were approached on the right, 34 let the researcher bum a smoke, compared with 17 of 88 whom she approached on the left.

“The present work is one of the few studies demonstrating the natural expression of hemispheric asymmetries, showing their effect in everyday human behavior,” write psychologists Daniele Marzoli and Luca Tommasi of the University G. d’Annunzio in Italy in the journal Naturwissenschaften.

It’s the latest in a series of studies that show that sound from both human ears is processed differently within the brain. Researchers have noted that humans tend to have a preference for listening to verbal input with their right ears and that given stimulus in both ears, they’ll privilege the syllables that went into the right ear. Brain scientists hypothesize that the right ear auditory stream receives precedence in the left hemisphere of the brain, where the bulk of linguistic processing is carried out.

Auditory modality + visual modality = faster perception

Science Daily reports:

The traditional view of individual brain areas involved in perception of different sensory stimuli—i.e., one brain region involved in hearing and another involved in seeing—has been thrown into doubt in recent years.

A new study shows that, in monkeys, the region involved in hearing can directly improve perception in the visual region, without the involvement of other structures to integrate the senses.

Integration of sensory stimuli has traditionally been thought of as hierarchical, involving brain areas that receive signals from distinct areas of the brain layer known as the cortex that recognise different stimuli. But the recent finding of nerve cells projecting from the auditory cortex (associated with the perception of sound) directly into the visual cortex (associated with sight), suggest that perception of one sense might affect that of another without the involvement of higher brain areas.

“Viral” yawning?

The LA Times reports on research from the UK on yawning:

A study published in the journal Biology Letters this week found that human yawns are contagious to dogs, a sign that man’s best friend may be capable of a rudimentary form of empathy.

To scientists, dogs have been a bit of a puzzle. Dogs are adept at reading human intentions and excel over other animals in picking up human hand gestures and other behavioral cues. At the same time, though, they appear to lack a sense of self, considered a prerequisite for understanding the feelings of others.

Unlike chimpanzees and possibly elephants and dolphins, dogs do not recognize themselves in a mirror, a classic test of self-awareness.

The latest study demonstrates that dogs are not completely egocentric in their relationships with humans but possess “some low-level attending to what others feel,” said Duke University anthropologist Brian Hare, who was not involved in the research.

“What’s fascinating about this study is that you would not expect to find contagious yawning where you did not have self-awareness,” he said.

Only humans and chimps are known to contagiously yawn.