Many researchers believe that one of the pivotal events in becoming human was the development of terrestrial bipedalism, or the ability to walk on two legs. Much has been made of our ancestors "coming down out of the trees." After all, the majority of our living primate relatives - for example, the great apes - still spend a great deal of their time in trees. In the primate family, humans are the only branch devoted to the ground, living terrestrial rather than arboreal lives. However, that wasn't always the case.

It is clear from the fossil records that our ancestors were tree dwellers until Lucy and her relatives arrived on the scene. Australopithecus afarensis appeared in Africa about 3.5 million years ago, and Lucy is the first specimen of this new species ever discovered. Anthropologists agree that A. afarensis was bipedal, but the question remains whether Lucy and her kin had totally forsaken the trees. Controversy over this question still rages today, prompting the new study by Dartmouth College. The findings of this study were recently published in the journal Proceedings of the National Academy of Sciences (PNAS).

"Australopithecus afarensis possessed a rigid ankle and an arched, nongrasping foot," writes Nathaniel Dominy, associate professor of anthropology at Dartmouth College, and his colleagues. "These traits are widely interpreted as being functionally incompatible with climbing and thus definitive markers of terrestriality,"

However, the new study indicates that this might not be the case after all. Based on data gathered during field studies in the Philippines and Africa, Dominy and his colleagues have brought new evidence to light by looking at modern humans who, like Lucy, have feet well adapted to terrestrial bipedalism. The results reveal that these people can still function as effective tree climbers.

On a sparkling New England afternoon, as hawks coasted overhead and yellow leaves drifted to the ground, Anne Pringle stood before a large granite obelisk that marked the graves of a family called French.

In this bucolic cemetery, steps from the headquarters of Harvard's research forest, she was pondering mortality. But she wasn't thinking about the Frenches. She was thinking about lichens.

Pale green and vaguely ruffled, like calcified doilies, lichens grow all over the tombstones and the old stone walls that fringe properties in this part of the world. Most people barely notice them. But Dr. Pringle, a mycologist at Harvard, believes they may help answer one of science's greatest questions: Is immortality biologically possible?

For eight years, Dr. Pringle, 42, has been returning to this cemetery each fall, to measure, sketch and scrutinize the lichens, which belong to the genus Xanthoparmelia. She wants to know whether they deteriorate with the passage of time, leaving them more susceptible to death.

Biologists call it senescence: the grim reality of decline with age. Are the lichens more likely to break apart as the years pass? Does their chemistry or bacterial composition change, leaving them more vulnerable to pathogens?

Chinese companies are using innovative business models to change the cost structures and capabilities involved in delivering renewable energy technology.

Through strategic partnerships with technology-led companies in the US and Europe, they are rapidly reducing the cost of production and effectively entering the value-added parts of the global technology economy.

In the popular imagination, China's industrial base is largely built on agriculture and manufacturing. This is still generally true. Agriculture employs an enormous proportion of the workforce and vast lands are dedicated to the painstaking process of growing rice or harvesting wheat. More recently, attention has been given to Chinese farmers leaving their hometowns in search of a better life in the city. Many of these migrant workers have moved into manufacturing or servicing China's immense construction boom. (The Chinese government alone has committed to building 20 new cities a year for the next decade.) But value-added goods and services are an increasingly important part of the Chinese economy - and the renewable energy sector is chief among them.

Many Chinese businesses in the clean tech space are adjusting their strategy in two ways. The first has been dubbed 'frugal innovation' by The Economist. Chinese businesses have found ways to make money from manufacturing high-tech goods in a low-tech way. Take BYD, China's leading battery manufacturer. Over the company's first 10 years its founder, Wang Chuan-Fu, brought the cost of the lithium ion battery down from US$42 to US$12. He is reported to have taken designs he had seen in Japan and replaced Japanese machinery with the hands of Chinese workers. Wang proved that it was possible to train large workforces to do repetitious tasks with minimal human error.

Johnson Tumai-Totorewa, 17, wasn't worried about the potential for 20-metre ocean swells as he embarked on a 10,000-nautical mile voyage on a waka hourua, double hulled sailing canoe today.

When his waka Ngahiraka Mai Tawhiti, and its elder sibling Te Aurere reach Rapanui/Easter Island in October it'll be the start of the cyclone season. He's not worried about that either.

The Mangere teenager, who said the trip was the first off the North Island, is the youngest of 23 sailors. But the only thing giving him twinges was how it would feel to miss someone, he said with a smile.

"My mummy. I'm a mummy's boy but everything else - well, I have confidence in all those around me. Most of all for me I think it's going to be awesome following in the footsteps of our tupuna."

The trip has been the dream of Hekenukumai Busby, the master waka builder who built both vessels. At 80 he is won't do the full trip but hopes to hop back on board as they get closer to the eastern tip of the Polynesian Triangle. Today, Mr Busby along with the Royal New Zealand Navy, a couple of hundred whanau and well-wishers farewelled the canoes with song and haka, the sounds echoing out over glassy Waitemata water.

In May 2009 super cyclone "Aila" swept the Sunderbans in eastern India and thousands of hectares of rice were ruined overnight and the area completely submerged in salt water. A handful of traditional rice farmers sowed three salt-tolerant rice varieties. These farmers were the only ones who harvested some rice in the following winter. These are not the imported and cross-bred "miracle high yielding hybrid rice" varieties about which our rice experts keep boasting day in and day out, all of which were devastated by the titanic Aila. Rather, they are the result of the painstaking work of one person, who, over the years, in a remote village in Odisha (Orissa), is preserving our age-old traditional rice varieties for posterity so that India does not lose its invaluable rice germplams.

Lit by a kerosene lamp, the two room hut just outside a sleepy hamlet in Odisha's Rayagada district can easily pass off as any other farmer's house in this tribal region. Step inside and one will be taken aback by the hundreds of earthern pots labelled with coded stickers stacked in a corner as well as under a bed. These pots treasure over 750 varieties of rice grains, some on the verge of extinction. The keeper of the seed bank, Debal Deb, has been collecting and conserving these rare native varieties over the last two decades. He does not hire "trained" agricultural experts. His only help are the farmers who continue to depend on "heirloom" (traditional) seeds, which have a glorious past.

More than 1000 Easter Islanders have given the crews of two Far North-built waka a rapturous welcome after an epic three-month journey from New Zealand.

The 20 sailors on board the waka hourua Te Aurere and Ngahiraka Mai Tawhiti first set eyes on Rapanui (Easter Island) late last week, but anchored offshore while 80-year-old master waka builder Hekenukumai (Hec) Busby flew to the island from his home at Doubtless Bay.

It had long been Mr Busby's dream to "close the Polynesian triangle" by sailing from Aotearoa to Rapanui using only traditional navigation techniques. The other sides of the triangle, from New Zealand to Hawaii and Hawaii to Easter Island, have already been sailed.

Once Mr Busby arrived the two waka completed their journey, chief navigator Jack Thatcher saying they were greeted by a rapturous welcoming party of more than 1000 people. They arrived at Anakena, on the northern side of Rapanui, at 9am on Thursday local time.

Mr Thatcher said the arrival was highly emotional because many sailors' family members had travelled from New Zealand to see them for the first time since they left Auckland in August.

When Japanese architect Shigeru Ban designed a new cathedral in earthquake-devastated Christchurch, he chose the most unlikely of materials -- cardboard -- for the landmark project.

The New Zealand city's magnificent Gothic revival cathedral hewn from local basalt was irreparably damaged in the 6.3-magnitude earthquake that claimed 185 lives on February 22 last year.

Urgently needing a temporary replacement, the Anglican Church commissioned Ban -- who donated his services gratis -- to draw up plans for a place of worship to house Christchurch's faithful.

The result is the so-called cardboard cathedral now taking shape on the quake-scarred city's skyline.

Built from 600-millimeter (24-inch) diameter cardboard tubes coated with waterproof polyurethane and flame retardants, it will be a simple A-frame structure that can hold 700 people.

"It will be a huge milestone towards recovery for Christchurch," project manager Johnny McFarlane said.

"It's going to be a great building to walk into, it's very light and airy and gives a good sense of dominance and scale."

Ban, a world-renowned architect who has been hailed by publications such as The Wall Street Journal and Time magazine, sees the cathedral as a way his profession can help Christchurch's shattered community recover from the quake.

Large sun-grazing comets could bring on the sort of global electronics meltdown usually associated with electromagnetic pulse weapons or a full-scale nuclear exchange.

Or so says David Eichler, lead author of a forthcoming Astrophysical Journal Letters paper positing that a sun-grazing comet roughly the size of Hale-Bopp (with a nucleus some 30 kms in diameter), could trigger cosmic ray-generating shockwaves large enough to initiate a global electromagnetic Armageddon.

Eichler, an astrophysicist at Israel's Ben-Gurion University of the Negev in Beer-Sheva, argues that satellites that weren't in protection mode would be wiped out along with most of the world's electronics - everything from micro-circuitry on cell phones to full-scale power stations.

If such a comet were the size of Hale-Bopp, Eichler says, the resulting solar flare would by far be the largest ever observed.

The comet gets compressed and then explodes in the solar atmosphere which, in turn, creates shockwaves, says Eichler.

Eichler thinks that such a sun-grazing comet may have triggered a large solar flare and cosmic ray-generating shockwaves as recently as 775 A.D., as indicated by tree ring analysis pointing to a sudden 1.2 percent spike in atmospheric Carbon 14.

"I'm not saying that [event] couldn't have been caused by a magnetic solar flare, but we've never seen a solar flare nearly that big," said Eichler.

Meteor showers can be spectacular to watch. Year round there are some great displays, from the Perseids in August, to the Geminids in December, to the Quadrantids in January. The peak displays and intensities vary somewhat by year though, so knowing when to watch and what to expect can be hard to know. So I've created this guide to what should be the best meteor showers of 2013.

Some general meteor shower watching tips:

Regardless of when the exact peak is, it's nearly always best to watch for meteors in the early morning, sometime between 1-3am. And always take into account the phase that the moon is in. If it's a bright moon, try to watch before the moon rises or after it sets.

The further away from city lights you can get, the better. A clear, dark sky is what you want. Getting comfortable with a reclining lawn chair and some blankets is also a good idea. Dress warmly, and maybe bring something warm to drink, like coffee or hot chocolate.

SOLAR CYCLE UPDATE: 2013 is only days away, and according to most forecasters, Solar Max should be approaching as well. But is it? Barely-increasing sunspot counts and anemic solar activity suggest an interesting possibility: Perhaps Solar Max is already here. (Below) This plot of measured vs. predicted sunspot numbers illustrates the idea: The blue curve traces monthly sunspot numbers measured since 2000. The red curve is the prediction of the NOAA-led Solar Cycle Prediction Panel.