What are memories really made of

London, Mar 31 (ANI): Performing a study on sea slugs—organisms known for a relatively simple nervous system—researchers at the University of California, Los Angeles have shown what are memories really made of.

It is already known that memory formation involves the strengthening of synaptic connections between nerve cells.

Last year, a team led by Kelsey Martin, became the first to watch memories being made in sea slugs, in the form of new proteins appearing at the synapses.

They wanted to find where is knowledge stored in the complex brains of mammals.

Short-term memories, such as a telephone number about to be used, seem to be stored in two small curled-up structures called the hippocampi, buried deep in the brain”s two hemispheres.

In 2008 Courtney Miller and David Sweatt at the University of Alabama in Tuscaloosa showed in mice that during the first hour after a memorable event there were chemical changes to the DNA of neurons in this area, altering the proteins produced.

Over the subsequent week, there were similar changes to the genes of neurons in the cortex, reports New Scientist.

These changes seemed to be permanent, indicating that long-term memories are stored there.

The pair believes that they watched short-term memories form in the hippocampus, which then became long-term memories in the cortex.

The brain pays extra attention to things that frighten us, as remembering them could mean the difference between life and death.

A structure next to the hippocampus called the amygdala is known to play a role in stamping this indelible mark.

Last year, a team led by Sheena Josselyn at the Hospital for Sick Children in Toronto, Canada, found that in mice they could erase a frightening memory of a noise by killing amygdala neurons whose synapses had recently been strengthened after exposure to the noise.

It was the first time a specific memory had been traced to the nerve cells that encoded it. (ANI)

Biased parrots better at problem-solving than ambidextrous counterparts

London, Sept 2 (ANI): Parrots that are strongly right- or left-footed are better at problem-solving tasks than their ambidextrous counterparts, according to a new study.

Lead researchers Maria Magat and Culum Brown at Macquarie University in Sydney, Australia, worked with eight species of Australian parrot, some of which are primarily left-biased – gang-gang cockatoos, for instance, are 100 per cent left-footed – others right-biased and the rest “ambidextrous”.

They studied their side preference by noting which eye they preferred for looking at food.

During the study, the researchers put the birds to various tasks, including foraging for different seeds sprinkled in a tray of pebbles and raising a hanging seed basket up to their beaks using their claws.

They found that the birds that had a strong bias towards using one side or the other were faster at the tasks than species that showed no preference between left or right.

All animals have cerebral lateralisation, meaning that their brains are divided into two hemispheres responsible for processing different tasks.

Strongly lateralised individuals are strongly “handed” – or strongly “footed” in the case of birds.

“Our study shows that strong lateralisation improves problem-solving ability and foraging in birds, which is an evolutionary advantage,” New Scientist quoted Brown as saying.

“It allows each side of the brain to become specialised at different tasks, so, for instance, the right side of the parrot’s brain can process foraging tasks without being slowed by interference from the left side of the brain,” the expert added.

The study appears in Proceedings of the Royal Society. (ANI)

Dino burrow find in Australia sheds light on long-term geologic change

Washington, July 11 (ANI): A team of paleontologists has found evidence of dinosaur burrows in Victoria, Australia, which would help shed light on long-term geologic change, and how organisms may have adapted as the Earth has undergone periods of global cooling and warming.

The find, by paleontologist Anthony Martin and his team from Emory University, US, suggests that burrowing behaviors were shared by dinosaurs of different species, in different hemispheres, and spanned millions of years during the Cretaceous Period, when some dinosaurs lived in polar environments.

In 2006, in collaboration with colleagues from Montana State University and Japan, Martin identified the 95-million-year-old skeletal remains of a small adult dinosaur and two juveniles in a fossilized burrow in southwestern Montana.

They later named the dinosaur species Oryctodromeus cubicularis, meaning, “digging runner of the lair.”

The researchers hypothesized that, besides caring for young in their dens, burrowing may have allowed some dinosaurs to survive extreme environments – throwing a wrench in some extinction theories.

A year after the Montana find, Martin traveled to the Victoria coast, which marks the seam where Australia once snuggled against Antarctica.

During a hike to a remote site known as Knowledge Creek, west of Melbourne, Martin rounded the corner of an outcropping and was astounded to see, right at eye level, the trace fossil of what appeared to be a burrow almost identical to the one he had identified in Montana.

The probable burrow etched into the Early Cretaceous outcrop is about six-feet long and one-foot in diameter. It gently descends in a semi-spiral, ending in an enlarged chamber.

Martin later found two similar trace fossils in the same area.

The Victoria fossils are about 110 million years old, around the time that Australia split with Antarctica, and dinosaurs roamed in prolonged polar darkness along forested southern Australia river plains.

It was one of the last times the Earth experienced global warming, with an average temperature of 68 degrees Fahrenheit – about 10 degrees higher than today.

The age, size and shape of the likely burrows led Martin to hypothesize that they were made by small ornithopod dinosaurs, which were herbivores that were prevalent in the region.

These ornithopods stood upright on their hind legs and were about the size of a large, modern-day iguana.

“It’s fascinating to find evidence connecting a type of behavior between dinosaurs that are probably unrelated, and lived in different hemispheres during different times,” Martin said.

“It fills in another gap in our understanding of the evolution of dinosaurs, and ways they may have survived extreme environments,” he added. (ANI)

Critical turning point can trigger abrupt climate change

Washington, April 21 (ANI): A new research by scientists from the Niels Bohr Institute indicates there can be changes in the CO2 levels in the atmosphere that suddenly reach a critical turning point and with that trigger dramatic climate changes.

The Earth’s climate is essentially contolled by three different cycles.

All three cycles are caused by the pull of the other planets in the solar system on the Earth, and one could say that they control the Earth’s climate by causing changes in the Sun’s radiation.

Solar radiation varies in the two hemispheres during the summer due to these cycles in the Earth’s tilt and the elliptical orbit and this has profound implications for whether ice caps can build up in the northern hemisphere, where the largest land areas are.

The ice ages have come and gone the last 20 million years and for the last few million years, we know with reasonable accuracy how often they come.

In the period before about 1 million years ago, the ice ages occurred around every 40.000 years, then it happened suddenly that the period changed so that it became circa 100.000 years between ice ages.

It is a mystery because nothing changed in the behaviour of the Earth’s orbit 1 million years ago. It is therefore due to a change that comes from the climate itself.

With completely new research results, geophysicist Peter Ditlevsen, Centre for Ice and Climate at the Niels Bohr Institute, has found part of the explanation for the mystery of the sudden change of the ice ages.

He has made model calculations of the climate of the past and compared it to the concrete data from seabed cores, which tell us about the climatic fluctuations of the past.

From the results, he has been able to construct a diagram over the possible climatic conditions resulting from the variation in solar radiation.

It appears that the ice ages and interglacial periods are not a gradual fluctuation between cold and warm climates.

What happened 1 million years ago was that the climate system went from a situation where it fluctuated between two states (cold and warm) with a 40.000 year cycle, corresponding to the dominant change in the Sun’s radiation.

The climate does not become gradually colder or warmer; it jumps from the one state to the other.

That which gets the climate to jump is that when the solar radiation changes and reaches a certain threshold – a ‘tipping point’, the existing climate state, e.g. an ice age, is no longer viable and so the climate jumps over into another state, e.g. a warm interglacial period. (ANI)

Evangeline Lilly once worked as a flight attendant

New Delhi, Feb 9 (ANI): Hollywood actress Evangeline Lilly was so desperate to travel around the world that she began working as a flight attendant.

However, the job didn’t stand up to her expectations, as it was terribly grueling, thus she finally quit and ventured into Hollywood, reports China Daily.

“I had no money. I was living on tea and peanut butter when I was a university student. I just wanted to travel so desperately that I would have done anything. I did the flight attendant training, which is grueling and hectic,” Evangeline said.

“I did the job for one month and then I quit. I hated it so much. I didn’t really get to see anywhere – I would go to Germany, and I’d be flying out the next morning. What’s the point of that?” Evangeline added.

After venturing into Hollywood, the ‘The Hurt Locker’ actress is grateful that her profession takes her to multifarious places around the world.

“Now I can see the world. Last summer, I went to seven different countries on two different sides of the Atlantic, in two different hemispheres, in two months,” Evangeline told The Dark Horizon website.

“I went to South America, to Argentina and Peru. And I went to Europe. I’ve also been to Japan and all sorts of other places. Russia is next on my hit list. I’ve got to go see Russia. And I’d like to go to Southeast Asia,” she added. (ANI)