Ancient DNA suggests dogs split from wolves 40,000 years ago

Man's best friend may be a very old friend indeed. An analysis of a bone from a newly identified ancient wolf species suggests dogs may have split from wolves as early as 40,000 years ago – with or without being domesticated at the same time.

Exactly when dogs started to be domesticated and split from wolves is a matter of some controversy. Archaeological evidence analysing the shapes of canid skulls found near early human camps suggested it might have happened as far back as 35,000 years ago. DNA analysis, focusing on differences between living dog and wolf genomes, seemed to suggest they must have split much more recently – between 11,000 and 16,000 years ago.

Now Love Dalén from the Swedish Museum of Natural History in Stockholm and colleagues have sequenced the genome of a wolf that lived 35,000 years ago in Taimyr, northern Russia, according to carbon dating. This allowed them to recalibrate the molecular clock – the rate at which genetic differences accumulate over time – and better reconstruct the wolf-dog evolutionary tree.

They found that dogs and wolves must have split into two separate lineages 27,000 to 40,000 years ago, bringing the DNA and archaeological evidence into line with each other.

They also found that some northern latitude dog breeds, having split from wolves, then interbred with the now extinct Taimyr wolf, which could have helped them adapt to the challenging northern environment. These breeds include the husky, Greenland sledge dog and, to a lesser extent, the Chinese shar pei and Finnish spitz.

But although the findings back an early split of dogs from wolves, they don't tell us when the domestication of dogs started. "The present study does not rule out the possibility of a very early date indeed, but it does not rule the possibility of a much later date either," says Laurent Frantz from the University of Oxford.

Perhaps humans didn't domesticate dogs once the creatures had split away from wolves: the alternative possibility is that there was an early split between two types of wolves, and that dogs emerged much later on one of these lineages. "We do not yet know whether it infers an early divergence between two wolf populations or between wolves and dogs," says Frantz.

Dalén says a combination of genomic and morphological work on ancient wolf or dog specimens is needed before we have a conclusive date on the time of domestication.

Mietje Germonpre of the Royal Belgian Institute of Natural Sciences in Brussels was one of the researchers who did the skull-shape work that suggested an early date of domestication. She is excited by the new findings, and says she is already studying a lot more specimens that should help clarify the question.

"I find it interesting that early modern humans might have been so resourceful that they started making use of dogs already during the height of the last Ice Age," says Dalén.

Journal reference: Current Biology, DOI: 10.1016/j.cub.2015.04.019

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Forget colour overlays – dyslexia is not a vision problem

A new study has discredited the theory that dyslexia is caused by visual problems. So what does cause the condition and how can it be treated?

What kind of visual problems are claimed to cause dyslexia?
A huge variety. They include difficulties in merging information from both eyes, problems with glare from white pages or the text blurring or "dancing" on the page. A host of products claim to relieve this so-called visual stress, especially products that change the background colour of the page, such as tinted glasses and coloured overlays.

Others advise eye exercises that supposedly help people with dyslexia track words on the page. Despite lack of evidence that these approaches work, some people with dyslexia say they help – more than half of university students with dyslexia have used such products.

What are the new findings?
That there's no evidence visual stress is linked with dyslexia. Nearly 6000 UK children aged between 7 and 9 had their reading abilities tested as well as performing a battery of visual tests. About 3 per cent of them had serious dyslexia, in line with the national average. But in the visual tests, the differences between the students with and without dyslexia were minimal. In two of the 11 tests, about 16 per cent of the children with dyslexia scored poorly, compared with 10 per cent for children with normal reading abilities. But that small difference could be caused by the fact that they read less, says author Alexandra Creavin of the University of Bristol, UK. And more importantly, the 16 per cent figure is so low, it can't be the main explanation for dyslexia.

So what does cause dyslexia?
We don't know. Various ideas have been put forward to explain why some children of normal or above-average intelligence have difficulty learning to read, but none of these theories have become generally accepted. Brendan Barrett of the University of Bradford in the UK says it may be more helpful to regard the condition as an unexplained difficulty with reading that doesn't necessarily reflect someone's intelligence. Many in the field now prefer the term "reading impairment" to avoid the unproven claims about dyslexia. "The term has a lot of baggage," says Barrett.

But those affected by the condition may have been written off as stupid, so appreciate having dyslexia as their "diagnosis".

How should we be treating the condition?
Evidence suggests that the best methods for helping people with dyslexia are the same as those that help anyone learn to read. The old-fashioned "phonics" method teaches individual letter sounds, then how to blend them together into words. People with dyslexia may just need a lot more of this kind of tuition than others. "But if you're spending time on eye exercises, that might be time not spent on phonics," says Creavin.

Who is pushing the coloured overlays?
There's a whole industry based on the visual stress theory, selling not only glasses and overlays but also consultations that can cost hundreds of pounds. "Families are very keen to help their children," says Cathy Williams, who also took part in the study. "There's a belief that in order to do right by their children, they must get hold of these products."

But dyslexia charities also need to be more sceptical, says Williams. A survey last year found that six out of eight UK dyslexia organisations were promoting such products on their websites uncritically and some general health websites accept their value. In a review for the UK's College of Optometrists, Barrett found that coloured overlays were not supported by evidence. But he says he has seen enough people who find them helpful to keep an open mind.

Journal reference: Pediatrics , DOI: 10.1542/peds.2014-3622

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Santa Barbara's oil-slicked waters

(Image: Brian van der Brug/Los Angeles Times via Getty Images)

This aerial photo shows part of Santa Barbara's coastline in California, after an estimated 21,000 gallons of oil spewed into the Pacific Ocean on Tuesday.

Taken on Wednesday, oil-soaked kelp darkened the water as efforts to mop up the spill continued.

The cause was a burst pipe, which leaked for 3 hours and released more than 100,000 gallons of oil in that time. Most of it remained on land, spreading across roughly 6.5 kilometres of beach, but enough leaked into the sea to form a 14-kilometre slick.

Many are concerned about the harm it will do to the area's wildlife, which includes whales and sea lions. Dead animals found so far include this oil-covered lobster.

(Image: David McNew/Getty Images)

The same area suffered a devastating spill in 1969, when a platform blowout released hundreds of thousands of gallons of oil into the sea, killing thousands of marine mammals and seabirds.

In the struggle to limit the damage this time, more than 300 people have been involved in clean-up efforts so far. Volunteers have been helping a crew of workers involved in cleaning the beach by raking and vacuuming up oil, and vessels have been deployed to remove oil from the sea surface.

(Image: ZUMA/REX_Shutterstock)

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Zoologger: Musical spider purrs like a cat to attract mates

Species: Gladicosa gulosa
Habitat: Leaf litter of beech-maple forests in the east of the US and Canada

With a sound like a wad of money being quietly thumbed, it's hardly a Handel aria.

But for the purring wolf spider, it's music. For the first time, a spider has been recorded producing what appear to be audible courtship signals over and above pure vibrations.

"It's very quiet, but it's what you would hear if you were in the room with a courting spider," says George Uetz of the University of Cincinnati in Ohio, who discovered the purring wolf spider with colleague Alexander Sweger. "The sound is at a level that's audible by human hearing at about a metre away."

Many spider species rely heavily on vibrations to send signals to one another, by shaking leaves or strands of their webs, for example.

Thrum away

But the purring wolf spider is different. While using their pedipalps – the appendages next to their mouthparts – to vibrate dead leaves, they also create an audible thrumming sound. Click here to listen to the spider.

The discovery is a puzzle, as spiders aren't known to have anything equating to "ears".

To check that the "thrum" isn't a bog-standard vibration signal, Uetz and Sweger used a vibration detector called a laser Doppler vibrometer to detect the drumming of the spider and convert it into an audible "sound" output.

Then they used a standard microphone to pick up the audible sound produced at the same time. Comparing the two showed that the vibration and the thrumming sound were two separate emanations.

The pair also found that males produce the sound and only females respond to a played recording of the purr, suggesting that the purr is used in courtship.

"We have yet to see any evidence of any male-to-male communication in this species," says Uetz.

Sensitive spiders

The males only produce the sounds if they are standing on something that will vibrate, like a leaf, and females only respond when perched on a similar surface.

Uetz and Sweger think that the signal reaches the female by travelling as sound in air, which causes the leaves a female is standing on to vibrate.

"We think that's how she 'hears' the sound," says Sweger. "Spiders have very sensitive structures all over their bodies for detecting vibration, even at low levels, so we're working on the hypothesis that they detect a surface vibration induced by the airborne sound."

The purring spiders may help us better understand how communication by sound first evolved. "Animal acoustic signals may originally have evolved from vibration, and our findings suggest a possible mechanism," says Sweger.

The pair reported their findings today at the annual meeting of the Acoustical Society of America in Pittsburgh, Pennsylvania.

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These sparkly sea organisms are an eerie omen of climate change

(Image: Jo Malcomson)

"All I can say is wow, just freakin wow!" says Lisa-Ann Gershwin from Australian Marine Stinger Advisory Services in Launceston, Australia.

This river in Southern Tasmania seemed to come alive this week as a bloom of Noctiluca scintillans – a type of bioluminescent plankton, also known as "sea sparkle" – washed into the region.

When it's disturbed, the organism produces light in its cytoplasm, the gel-like substance inside its single cell.

As news of the bloom spread, hundreds of people came to see the spectacle, says Gershwin. "People turned out in droves, rolled up their pant legs and danced, ran, splashed, stomped, tiptoed, you name it, people played! It was incredible!"

But there is a dark side to this impromptu festival of light. "The displays are a sign of climate change," says Anthony Richardson from the CSIRO, Australia's national science agency in Brisbane.

Until 1994, Noctiluca had not been seen in Tasmania. But global warming has been strengthening the East Australian current, which pushes warm water south towards Tasmania. "As the Southern Ocean warms, it will be warm enough for Noctiluca to survive," says Richardson.

What's more, these particular plankton have more direct impacts too. "Noctiluca is a voracious feeder on diatoms, which is the food for krill in the Southern Ocean," says Gustaaf Hallegraeff from the University of Tasmania in Hobart. Dense blooms like this can therefore starve other organisms, he says. They can also kill fish through oxygen depletion and gill irritation.

"As wondrous and entertaining as Noctiluca is, it is also a species infamous for causing fish kills," says Gerhswin. But what the outcome will be from this particular bloom remains an unresolved question, adds Hallegraeff. "Blooms can disappear within days, leaving essentially no trace."

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First human head transplant could happen in two years

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A radical plan for transplanting a head onto someone else’s body is set to be announced. But is such ethically sensitive surgery even feasible?

IT'S heady stuff. The world's first attempt to transplant a human head will be launched this year at a surgical conference in the US. The move is a call to arms to get interested parties together to work towards the surgery.

The idea was first proposed in 2013 by Sergio Canavero of the Turin Advanced Neuromodulation Group in Italy. He wants to use the surgery to extend the lives of people whose muscles and nerves have degenerated or whose organs are riddled with cancer. Now he claims the major hurdles, such as fusing the spinal cord and preventing the body's immune system from rejecting the head, are surmountable, and the surgery could be ready as early as 2017.

Canavero plans to announce the project at the annual conference of the American Academy of Neurological and Orthopaedic Surgeons (AANOS) in Annapolis, Maryland, in June. Is society ready for such momentous surgery? And does the science even stand up?

The first attempt at a head transplant was carried out on a dog by Soviet surgeon Vladimir Demikhov in 1954. A puppy's head and forelegs were transplanted onto the back of a larger dog. Demikhov conducted several further attempts but the dogs only survived between two and six days.

The first successful head transplant, in which one head was replaced by another, was carried out in 1970. A team led by Robert White at Case Western Reserve University School of Medicine in Cleveland, Ohio, transplanted the head of one monkey onto the body of another. They didn't attempt to join the spinal cords, though, so the monkey couldn't move its body, but it was able to breathe with artificial assistance. The monkey lived for nine days until its immune system rejected the head. Although few head transplants have been carried out since, many of the surgical procedures involved have progressed. "I think we are now at a point when the technical aspects are all feasible," says Canavero.

This month, he published a summary of the technique he believes will allow doctors to transplant a head onto a new body (Surgical Neurology International, doi.org/2c7). It involves cooling the recipient's head and the donor body to extend the time their cells can survive without oxygen. The tissue around the neck is dissected and the major blood vessels are linked using tiny tubes, before the spinal cords of each person are cut. Cleanly severing the cords is key, says Canavero.

The recipient's head is then moved onto the donor body and the two ends of the spinal cord – which resemble two densely packed bundles of spaghetti – are fused together. To achieve this, Canavero intends to flush the area with a chemical called polyethylene glycol, and follow up with several hours of injections of the same stuff. Just like hot water makes dry spaghetti stick together, polyethylene glycol encourages the fat in cell membranes to mesh.

Next, the muscles and blood supply would be sutured and the recipient kept in a coma for three or four weeks to prevent movement. Implanted electrodes would provide regular electrical stimulation to the spinal cord, because research suggests this can strengthen new nerve connections.

When the recipient wakes up, Canavero predicts they would be able to move and feel their face and would speak with the same voice. He says that physiotherapy would enable the person to walk within a year. Several people have already volunteered to get a new body, he says.

The trickiest part will be getting the spinal cords to fuse. Polyethylene glycol has been shown to prompt the growth of spinal cord nerves in animals, and Canavero intends to use brain-dead organ donors to test the technique. However, others are sceptical that this would be enough. "There is no evidence that the connectivity of cord and brain would lead to useful sentient or motor function following head transplantation," says Richard Borgens, director of the Center for Paralysis Research at Purdue University in West Lafayette, Indiana.

If polyethylene glycol doesn't work, there are other options Canavero could try. Injecting stem cells or olfactory ensheathing cells – self-regenerating cells that connect the lining of the nose to the brain – into the spinal cord, or creating a bridge over the spinal gap using stomach membranes have shown promise in helping people walk again after spinal injury. Although unproven, Canavero says the chemical approach is the simplest and least invasive.

But what about the prospect of the immune system rejecting the alien tissue? Robert White's monkey died because its head was rejected by its new body. William Mathews, chairman of the AANOS, says he doesn't think this would be a major problem today. He says that because we can use drugs to manage the acceptance of large amounts of tissue, such as a leg or a combined heart and lung transplant, the immune response to a head transplant should be manageable. "The system we have for preventing immune rejection and the principles behind it are well established."

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Say hello to machines that read your emotions to make you happy

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The latest AI devices can't just gauge your mood from what you say and how you say it, they can work out the best way to respond to cheer you up

"BRIAN? How are you, Brian?" The voice is coming from a screen dominated by a vast blue cartoon eyeball, its pupil dilating in a way that makes it look both friendly and quizzical. Think HAL reimagined by Pixar.

This is EmoSPARK, and it is looking for its owner. Its camera searches its field of view for a face and, settling on mine, asks again if I am Brian. It sounds almost plaintive.

EmoSPARK's brain is a 90-millimetre Bluetooth and Wi-Fi-enabled cube. It senses its world through an internet connection, a microphone, a webcam and your smartphone. Using these, the cube can respond to commands to play any song in your digital library, make posts on Facebook and check for your friends' latest updates, stream a Netflix film, answer questions by pulling information from Wikipedia, and simply make conversation.

But its mission is more complex: EmoSPARK, say its creators, is dedicated to your happiness. To fulfil that, it tries to take your emotional pulse, adapting its personality to suit yours, seeking always to understand what makes you happy and unhappy.

The "Brian" in question is Brian Fitzpatrick, a founding investor in Emoshape, the company that makes EmoSPARK. He and the device's inventor, Patrick Levy Rosenthal, compare EmoSPARK's guiding principles to Isaac Asimov's laws of robotics. They are billing the cube as the world's first "emotional AI".

But EmoSPARK isn't the first robotic agent designed to learn from our emotions. There's Jibo the family robot and Pepper the robot companion. Even Amazon's Echo voice-activated controller might soon be able to recognise emotions.

The drive to give artificial intelligence an emotional dimension is down to necessity, says Rana el Kaliouby, founder of Affectiva, a Boston-based company that creates emotion-sensing algorithms. As everything around us, from phones to fridges, gets connected to the internet, we need a way to temper machine logic with something more human.

And when the user is immersed in a world that is as much computer as real life, a machine must learn some etiquette. For example, you shouldn't come home from a funeral to find your AI itching to tell you about the latest Facebook cat videos.

How can a machine be trained to understand emotions and act on them? When EmoSPARK's webcam finds my face, a red box flashes briefly on screen to indicate it has identified a face that isn't Brian's. Behind the scenes, it is also looking for deeper details.

EmoSPARK senses the user's emotional state with the help of an algorithm that maps 80 facial points to determine, among other things, whether he or she is smiling, frowning in anger or sneering in disgust. EmoSPARK also analyses the user's tone of voice, a long-established method of mood analysis.

Having sensed these details, EmoSPARK uses them to mirror your emotions. First, it creates an emotional profile of its owner based on the combination of facial and voice input. At the end of each day, it sends this information to EmoShape, which sends back a newly tailored emotional profile for that particular device. Through this feedback loop, Fitzpatrick says, the cube's personality changes ever so slightly every day.

Hard problems

Rosalind Picard at the Massachusetts Institute of Technology is sceptical that this can produce an accurate emotional profile. Picard, who designs facial and vocal analysis software to help computers interpret emotion, and co-founded Affectiva with el Kaliouby, says there's more to understanding moods than mapping points on the face. "What does it know about the context? How much data is it trained on? How is it being taught the true feelings of the person? These are still hard problems to solve."

The algorithm used by EmoSPARK isn't necessarily all that sophisticated. Coaxing it to register a user's smile requires a toothy grin in good lighting; real-world conditions, for most people, don't live up to that.

But maybe you don't need a million-dollar algorithm. One aspect of creating "emotional" AI requires neither hardware nor software: it's just a matter of exploiting what our brains do naturally. "We anthropomorphise everything," says Eleanor Sandry at Curtin University in Perth, Australia. Humans project intent and emotions on to anything from dolphins to Microsoft's paper clip. We can't help ourselves.

And EmoSPARK pulls out all the stops to put this tendency to work. To calibrate your cube, you undertake a ritual which ensures that only one person can be emotionally bound to it. "Are you the person I am to bond with?" is its first question. Although it will recognise other individuals in the same house or building, it only creates the emotional profile for its owner.

That doesn't mean it can't interact with anyone else. When someone who is not Brian taunts it, saying "I don't like you", EmoSPARK manifests its displeasure with a pulse of green light that shudders through the cube. "It's funny, I don't like you that much either," it responds. If EmoSPARK had been complimented, it would have glowed purple.

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