Smithsonian.com

Coal-fired stoves are a major source of black carbon. Photo: Michael Davis-Burchat

Black carbon—an atmospheric pollutant “formed by the incomplete combustion of fossil fuels, biofuels, and biomass“—holds an even tighter grip on the Earth’s climate than we thought. Based on new research by scientists with the International Global Atmospheric Chemistry project, black carbon may in fact be the second most important factor driving modern anthropogenic climate change.

According to a news release by the American Geophysical Union, which published the study, cutting back on black carbon emissions would have “an immediate cooling impact.” One of the study’s authors, Tami Bond, says:

“This study shows that this is a viable option for some black carbon sources and since black carbon is short-lived, the impacts would be noticed immediately. Mitigating black carbon is good for curbing short-term climate change, but to really solve the long-term climate problem, carbon dioxide emissions must also be reduced.”

In Asia and Africa, coal and biomass burning are the main culprits of black carbon emissions. In North America, Latin America and Europe, it’s diesel engines.

But wherever it comes from, black carbon messes with the Earth’s climate in a number of ways. Black carbon absorbs sunlight, trapping heat. It seeds clouds, which both trap heat and reflect sunlight. And by reacting with other chemicals in the atmosphere, it creates a range of downstream effects. Unlike carbon dioxide, the effects of which are felt world-wide owing to its long stay in the atmosphere, the effects of black carbon are often much more local.

All in all, says the study, black carbon is accountable for trapping around 1.1 watts of energy per square meter of the Earth’s surface every year. This value, 1.1 W/m^2, compares with the 1.56 W/m^2 of energy trapped by carbon dioxide and the 0.86 W/m^2 trapped by methane, another greenhouse gas. However, the uncertainty wrapped up in the measure of black carbon’s potential is huge: the 1.1 W/m^2 comes with an uncertainty of 90%, meaning that the real energy-trapping potential could realistically fall anywhere from 0.17 to 2.1 watts per square meter.

The uncertainty in the measure of black carbon’s effect on the Earth’s energy budget comes from a few places, the authors say. No one has pinned down exactly how black carbon’s interactions with clouds affect energy trapping. Nor is there a solid number for the total amount of black carbon being emitted each year. Sorting these values out to a higher degree of precision would cut down some of the uncertainty in understanding black carbon’s role as a heat trapper.

Even still, realizing the warming potential of black carbon also points to an opportunity to mitigate on-going warming. The BBC:

“Reducing emissions from diesel engines and domestic wood and coal fires is a no-brainer as there are tandem health and climate benefits,” said Professor Piers Forster from the University of Leeds.

“If we did everything we could to reduce these emissions we could buy ourselves up to half a degree less warming, or a couple of decades of respite,” he added.

Half a degree of warming is much less than the total expected warming we are set to face, but with modern warming already starting to affect people’s daily lives, it is likely worth trying anything that could bring temperatures down.

The results come on the heels of reports by both NASA and the National Oceanic and Atmospheric Administration that, globally, 2012 was one of the warmest years on record, with the top 10 years all occurring within the past 14 years.

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Photo: patries71

Human ideals about fairness may not be so human after all, new research finds. A sense of innate fairness may have evolved long before Homo sapiens began playing rock-paper-scissors to decide which team would bowl first. Chimpanzees, the BBC reports, beat us to it. The great apes possess an innate sense of fairness that researchers think likely served as an important foundation of building cooperative societies such as our own.

To tease out the specifics of chimps’ sense of fairness, researchers challenged the animals to the “ultimatum game.”

During the game, one participant is given an amount of money and asked to “make an offer” to the second player. If that second player accepts the offer, the money is divided accordingly.

But, if the second player refuses that offer, both players receive nothing. This is the basis of the fairness versus economics quandary; if the first player proposes a selfish, unequal offer, the affronted recipient might refuse.

And this is exactly what happens in humans. Although it makes economic sense to give away as little as possible and accept any offer that’s proposed, people usually make roughly equal, or “fair” offers, and tend to refuse unequal or “unfair” offers.

For monkeys, the researchers tweaked the game to include banana slices rather than money. A bit abstractly, colored tokens represented banana slices, which the researchers taught the chimps to recognize as such. Taking a white token meant the food got split up equally, while blue tokens gave the first chimp all of the tasty rewards. The researchers presented one chimp with the two tokens. The chimp would then chose a token and offer it to its partner. Just like in the human version, the partner needed to accept the token before either animal received a reward.

From observing three pairs of chimps, the researchers saw that the teams tended to work fairly together and equally share the food reward. The researchers guess that sharing, cooperation and fairness helped chimp ancestors survived, since groups that worked together to care for young, find food and defend against predators had better odds for passing on their genes to the next generation. A strong sense of fairness and tendency towards sharing likely existed in chimpanzees at least as long as the time at which humans and chimps split off from the evolutionary tree, the researchers think.

The researchers also noted to the BBC that in tests with 20 children between the ages of two and seven, just like the chimps, the youngsters  ”responded like humans typically do.”

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Did ancient Australians witness a similar scene? Photo: Gunter Senft/MPI for Psycholinguistics

Outside of Africa, Australia holds some of modern humans’ earliest archeological evidence, with relics dating back to about 45,000 years ago. In other words, Australian aboriginals are the oldest continuous population of humans on the planet, besides those found in Africa. But these populations did not remain quite as isolated as researchers originally thought.

Anthropologists and historians always assumed that from the time the first human settlers stumbled upon Australia to the moment European sailors arrived in the late 1800s, Australia remained unknown to the rest of the world. But new research refutes this commonly held belief with evidence of substantial gene flow between Australian and Indian populations millennia ago.

Genetic variation across aboriginal Australians’ genomes point to influence from India around 4,230 years ago, well before Europeans could even dream of exploring the far-off continent. Around the same time, the researchers noticed, archeological changes occur in the Australian record, including shifts in the way ancient humans processed plants and created stone tools. At this time, spears and dingos also first appeared in the fossil record. People from the Indian subcontinent may have arrived, bringing with them new species, technologies and cultures.

How they managed to make that approximately 5,000 mile journey, however, remains a mystery, at least for the time being.

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Animal sex is a strange thing to us. Spiders eat their mates, honey bees’ testicles explode, garter snakes have giant orgies, and snails have their genitals on the necks. But there are also all sorts of animals that we actually have never seen get it on. Squid were one of them. But no longer! Scientists have finally filmed some squid sexy times, and here is the footage:

Scientists from the Monterey Bay Aquarium Research Institute and Smithsonian’s Museum of Natural History describe the squid love this way:

Undaunted by the bright lights of the remote controlled sub filming their activity some 1,400 meters down in the Gulf of Mexico, the two deep-sea squid (species:Pholidoteuthis adami) maintained their unusual but intimate position. The male was upside down on top of the hovering female, gripping her firmly; their bodies parallel but pointing in opposite directions.

Clearly visible connecting the dark-purple cephalopods is the white “terminal organ” or penis of the male, extending out through the male’s funnel. (A jet-propelled squid forcibly squirts water through its funnel, causing its body to shoot forward tail first.)

Scientists had a lot of guesses about how squids might have mated, based on examining their anatomy. That “terminal organ” they talk about above was assumed to, well, do what it does. But it doesn’t exactly work the way they predicted. Here are the scientists again:

“People have guessed how the terminal organ was used, but in some ways they guessed wrong,” explains Michael Vecchione, a research zoologist at the Smithsonian’s National Museum of Natural History…. “We knew the terminal organ was located in the mantle of the male but we didn’t know that it projected through the funnel. The male was upside down, that also was surprising.”

Sounds perfect for a squid episode of Isabella Rossellini’s Green Porno.

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A female H. floresiensis recreation from the Smithsonian Museum of Natural History. Photo: dctim1

Archaeologists are slowly bringing “the Hobbit Human” to light as new bones turn up and add pieces to the puzzle of what this ancient Homo species looked like. The latest findings, three wrist bones, were unearthed in Flores, Indonesia, and provide further evidence that H. floresiensis did indeed exist, refuting claims by other researchers that hobbits were just human pygmies.

“The tiny people from Flores were not simply diseased modern humans,” Caley Orr, lead author of the paper describing the finding in the Journal of Human Evolution, told Discovery News.

Science News provides some background:

Hobbits died out around 17,000 years ago, after having descended from a member of the human evolutionary family that must have reached Indonesia by 1 million years ago, the researchers propose.

Hobbits’ wrists limited their ability to make and use stone tools, the scientists contend. Basic stone cutting implements excavated on Flores date to 800,000 years ago.

The hobbits stood about 3’6” tall—within the range of J.R.R. Tolkien’s fictional hobbits, said to stand between 2 to 4 feet. They also had long, broad feet like Tolkien’s characters.

Like modern humans, the Flores hobbits walked on two legs and had small canine teeth. They lived a cave man lifestyle, and researchers have found ancient remnants of stone tools, animal bones and fire in caves on the island.

Unlike modern humans, however, hobbit arms were longer than their legs, Discovery points out, giving them a more ape-like structure. Their inferred small brain size puts them on par with a chimpanzees for IQ.

The Hobbit’s wrist looked like that of early human relatives, such as Australopithecus, but the key ancestral candidate now is Homo erectus, “Upright Man.”

It is possible that a population of H. erectus became stranded on the Indonesian island and dwarfed there over time. Orr said that “sometimes happens to larger animals that adapt to small island environments.”

A problem, however, is that H. erectus is somewhat more modern looking than the Hobbit, so researchers are still seeking more clues.

The researchers hope to tease out how the Flores hobbits managed to make stone tools with their relatively primitive hands and wrists. “H. floresiensis solved the morphological and manipulative demands of tool-making and tool-use in a different way than Neanderthals and ourselves,” Orr told Discovery News.

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