Nature Newsblog
« June 2007 | Main | August 2007 »
Running and caffeine guard against skin cancer in mice.
Exercise and caffeine combine to fight skin cancer, researchers say. Mice that mix the stimulant with daily running fight the cell damage caused by ultraviolet light better than animals that merely run or drink caffeine-laced water.
Read the story here.
Tumours on tumours might limit lethal disease in large animals.
Cancer may be more common but less lethal in large animals, say researchers modelling cancer formation. They suggest that tumours in large animals may spawn even more aggressive tumours that stunt their parents' growth.
Read the story here.
Genetic differences affect recall of positive and negative events.
A single gene can influence how clearly you recall emotionally intense memories, neuroscientists have shown. This finding could aid the search for therapies for people traumatized by horrific experiences.
Read the story here.
After a full session of talks today, the conference breaks tomorrow for a set of all-day field trips. I’ll be off to visit the Undara lava tubes – one of the world’s longest such systems – so no news of the Quaternary for 24 hours or so.
One of the fun things about conferences is stumbling across little gems of presentations – things that may not be earthshattering news, but are just fun to listen to for 15 minutes. Today, Niels Schroeder of Roskilde University in Denmark served up such a little talk, entitled “Tales and Facts: Beowulf and Lejre”.
Danish archaeologists have apparently conducted a couple of excavations over the past decade trying to see whether the city of Lejre, in ancient Denmark, is in fact the site of the royal hall mentioned in the epic medieval poem Beowulf. In just the past couple of years, the archaeologists have uncovered remains of a large hall that they say may be the legendary hall of Heorot. And geologists have tried to pinpoint lakes or swamps that could have been the location for the lair of the monster Grendel.
A medieval research center at Arizona State University has more information about a new book on this topic on its webpage.
INQUA organizers have thoughtfully selected the lovely tropical city of Cairns, in the state of Queensland, for this conference. Many attendees seem to be taking the opportunity to bring their families along for some side trips to the Great Barrier Reef and the Daintree rainforest. And for those poor souls who have to get stuck at the actual conference, meeting planners have sweetened the deal a bit. So far, the Cairns convention center has just about the best convention food I’ve ever eaten (and I’ve eaten a lot – trust me, eating with the physicists in Minneapolis in March was a definite culinary low point).
Although Cairns is a relatively small city, it’s tried to draw conference traffic with its convention center. The combination of family day trips and tropical setting appears to work – just a few weeks ago, the city also played host to the major stem-cell conference of the year, the International Society for Stem Cell Research.
My colleague who went to that meeting said she though Australian food was quite pedestrian. I’m planning to circumvent that problem tonight by going to a local restaurant that promises smoked kangaroo, crocodile wontons, and emu pate. Bon appetit!
The first thing you may be wondering, gentle reader, is what exactly is Quaternary research? Simple – it’s anything that addresses the last 1.8 million years or so. ‘Quaternary’ means fourth, and geologists introduced the term to differentiate the period from the earlier Tertiary (third) period of geologic time.
The Quaternary is important, INQUA folks will tell you, because a lot of important things have happened in the last couple of million years. Hominids arose in Africa, became modern humans, and spread around the world. Ice ages came and went. Great animals rose and became extinct. It has been a busy time.
INQUA itself meets only every four years, and topics at the meeting range from paleoclimate (what happened on the Tibet plateau during the last couple of glaciations?) to human evolution (when and how did people colonize Australia, and what effect did they have on the landscape when they did?). Meeting organizers are trying to cram in a lot, and the 1,000 people attending this conference will have all week to try to make sense of things.
And so it’s off to the races…
Space agency hit by claims of theft, sabotage and drunkenness.
NASA’s reputation took a battering this week as the space agency’s staff faced a range of misconduct allegations, including allowing astronauts to fly when drunk, the deliberate sabotage of a computer for a forthcoming shuttle flight, and failing to stop the loss of equipment worth nearly $100 million.
Read more here
Frequent use more than doubles psychosis risk, says new large-scale analysis.
Frequent cannabis use more than doubles the risk of developing psychotic illnesses such as schizophrenia, according to the most rigorous analysis of the evidence to date.
Read more here
Mutant mice live longer, age slower and eat more.
Researchers have created a mutant mouse that lives longer despite eating more and weighing less — all thanks to the loss of a single protein.
Read more here
'Trojan chromosomes' enlisted in battle against alien invaders.
Gender-bending chemicals could provide a new way to combat invasive species, say researchers. Originally conceived as a cure for the enormous populations of Asian carp and tilapia plaguing the Mississippi River, scientists now think the approach could be used to battle unwelcome crustaceans, molluscs, fish, amphibians and reptiles around the world.
Read more here
Atom-thick sheets stacked to make strong ultra-thin material.
Researchers have used a recently discovered form of carbon to make sheets of super-stiff and super-strong paper that is only a few millionths of a metre thick. This paper could lead to the development of tough new materials or be used to store energy for fuel cell applications.
Read the story here.
Study finds no evidence of symptoms from electromagnetic waves.
There is no evidence that short-term exposure to signals from mobile telephone masts causes illness, say British researchers who have carried out a trial involving dozens of people who claim to be sensitive to the signals.
Read the story here.
Effect seems to work regardless of a person's beliefs.
A belief in God may have promoted the evolution of cooperative behaviour, say Canadian psychologists. They found that priming people with religious concepts makes them more generous — regardless of whether they declare themselves to be believers.
Read the story here.
This week the Nature Podcast surveys the scientific side of the Simpsons, discovers how humans are changing rain patterns, and finds out how a project that gives palm pilots to pygmy communities is putting their interests on the map.
To SUBSCRIBE to the Nature Podcast for FREE copy and paste this URL into iTunes or your preferred media player or RSS reader:
http://www.nature.com/nature/podcast/rss/nature.xml
Plane takes medical workers to a pardon in Bulgaria.
A French government aircraft carrying six medical workers convicted of deliberately infecting children with HIV touched down in Sofia, Bulgaria, on 24 July, ending their 8-year ordeal in a Libyan prison.
Read the story here.
Life-building molecules might be spread throughout space.
Astronomers have found the largest negatively charged molecule so far seen in interstellar space. The discovery, of an organic compound, suggests that the chemical building blocks of life may be more common in the Universe than had been previously thought.
Read the story here.
Half of all cases of male autism may be caused by spontaneous genetic mutations, say researchers who have studied the genetic patterns of the condition. Offspring who inherit such mutations are at a greater risk of having an autistic child themselves.
Read the story here.
Ancient tooth reveals elephants' family tree.
The mastodon, an extinct relative of modern elephants, has become the latest prehistoric animal to have its DNA sequenced.
Read the story here.
Voracious mollusc sets up home in the North Pacific.
Mexican fishermen call it diablo rojo — the red devil. A film-maker wears armour when he goes near it. And the Humboldt, or jumbo, squid (Dosidicus gigas) is on the move, swimming north from the tropics and eating its way into commercial fish stocks.
Read the story here.
Greenhouse-gas emissions have made the Northern Hemisphere wetter.
Human activity has made the weather wetter in a large slice of the Northern Hemisphere, say researchers. It has also made the regions just south of the Equator wetter, and those just north of it drier.
Read the story here.
Jumping jets move from the bathroom to the kitchen.
After bouncing shampoo, physicists now bring you bouncing cooking oil. A team in Texas has found that the trampolining of a liquid jet falling onto a bath of the same liquid is more common than expected.
Read the story here.
If you do try this at home feel free to post YouTube links in the comments for our edification and amusement...
Scans reveal a fluid-filled cavity in the brain of a normal man
Three years ago, a 44-year-old man was admitted to hospital in Marseille, France, complaining of weakness in his left leg. He had no idea what doctors would find to be the source of the problem: a huge pocket of fluid where most of his brain ought to be.
read the story here
Bipolar episodes decrease brain size, and possibly intelligence
Grey matter in the brains of people with bipolar disorder is destroyed with each manic or depressive episode.
This was the finding of an MRI study of 21 patients with bipolar disorder, a mental illness marked by successive episodes of mania followed by deep depression. The patients' brains were scanned at either end of a four-year period, during which time each patient had at least one episode and some as many as six.
read the story here
Computer program is unbeatable at English draughts
Long-time world checkers champion Marion Tinsley consistently bested all comers, losing only nine games in the 40 years following his 1954 crowning. He lost his world championship title to a computer program in 1994 and now that same program has become unbeatable; its creators have proved that even a perfectly played game against it will end in a draw.
Read the story here
Honeybee queens may use scent to stay popular in negative situations.
Honeybee queens produce a chemical cocktail that politicians would swarm to get their hands on: the scent of a queen keeps her drones and workers loyal to the throne, dutifully feeding and grooming their ruler.
Read the story here
Fiddler crabs rid excess lead from their system by moulting.
Shedding an old shell could be about more than just getting too big for it. Crustaceans living in polluted waters may dispose of toxic metals by dumping their old casings, say researchers.
Peruvians decide to ban transgenic crop from the potato homeland.
This Thursday, the government of Cusco, a region in the Peruvian Andes, is scheduled to ban all genetically modified (GM) varieties of potato, according to the London-based International Institute for Environment and Development (IIED). The area was the birthplace of many varieties of spud, and is still home to thousands of kinds of potato, from the notoriously hard to peel q'achun waq'achi to the dark grey amakjaya.
This week the Nature Podcast finds two proteins that battle aging as well as cancer, plumbs the depths of the English Channel to discover how it was formed, gets stuck on a super-sticky polymer, and explores the universe’s ‘dark side’.
To SUBSCRIBE to the Nature Podcast for FREE copy and paste this URL into iTunes or your preferred media player or RSS reader:
http://www.nature.com/nature/podcast/rss/nature.xml
Emma Marris finds out how two South Africans in the field are convincing business and government to value biodiversity.
Protecting nature within the context of human activity is a complicated thing to do; and it can be even harder to convince people to do it. One way that people try to make sure that nature is protected is through 'mainstreaming' — integrating ecological goals into the practices of businesses and governments.
Nature's Emma Marris sat down with two people who are trying this in South Africa. Read the interview here.
'Cryovolcanoes' may spew snow over Pluto's neighbour
Pluto's neighbouring object, Charon, could be spewing out liquid water from ultra-cold volcanoes, covering Charon's chilly surface with freshly-formed ice crystals.
read the story here
An extra copy of a tumour-killing gene helps mice to stay young.
A protein known to keep cancer at bay now also looks to be a fountain of youth. Mice with an extra copy of the tumour-killing gene that pumps out this protein live longer than those with just one copy, and are better at combating the cell damage that causes ageing.
Expecting a big reward helps the reward to come true.
Neuroscientists have found that people who experience a strong dose of pleasure at the thought of an upcoming reward are more susceptible to the placebo effect.
Read more here
Geological evidence supports theory of surge down the English Channel.
The island that is now England, Scotland and Wales was severed from continental Europe by a cataclysmic flood during the last ice age, according to a group of researchers based in Britain.
Andrew Wakefield's status as doctor is under review.
Uptake of the measles, mumps and rubella (MMR) vaccine plummeted in Britain after doctor and researcher Andrew Wakefield suggested in 1998 that it could be linked to autism — a suggestion that made huge waves in the media and with the public. Subsequent studies have ruled out a link between MMR and autism, and the majority of medical opinion now firmly rejects Wakefield's hypothesis. This week, Wakefield stands before a hearing at the General Medical Council (GMC) — the body that regulates doctors in the United Kingdom.
Forcing lefties to be righties results in more brain activity.
'Southpaw', 'goofy', or just plain 'lefty' are some of the many names that left-handers have been called. In certain societies, the aversion can go so far that some left-handers are forced to write with their right hand, regardless of their natural tendencies.
Rapid acceleration shakes up more than the ground in Japan.
An earthquake off the western coast of Japan yesterday hit a nuclear plant with more than twice the jolt that the plant was expected to have to handle. The shock seems to have done little immediate damage, but has raised concerns about whether Japan's nuclear plants are designed to withstand the kind of shaking they are likely to experience.
Some are more efficient on two feet than four.
It seems that some chimps surprisingly use less energy walking on two feet than they do loping around on all four limbs. The researchers who discovered the expert walking ability of one chimp say it may help to explain how the earliest humans adapted to standing upright.
Immune protein makes the body clock turn down a notch.
Getting sick often means getting tired too. Now researchers have tracked down how the chemical responsible for such drowsiness works.
Mathematicians solve 75-year-old mystery of infinite loop's shape.
Eugene Starostin's desk is littered with rectangular pieces of paper. He picks one up, twists it, and joins the two ends with a pin. The resulting shape has a beautiful simplicity to it — the mathematical symbol for infinity () in three-dimensional form. "Look," he says, as he traces his finger along its side, "whatever path you take, you always end up where you started."
Real science can't compete at the movies with bad science. But perhaps that's how it is meant to be.
"I'm arresting you for breaking the laws of physics," says the policeman to the levitating man, in a cartoon that speaks volumes about the curiously legalistic terminology that science sometimes adopts.
Read more here.
Alternative fuels push for entry to UK speed trials.
Undergraduate engineers will be racing their cars this weekend at Silverstone — home of the British Grand Prix — in the tenth Formula Student competition.
Read the story here.
Reduced agricultural productivity seems to trigger armed conflict.
Most of the armed conflicts in eastern China over the past 1,000 years were triggered by food shortages caused by climate, say researchers.
Read the story here.
Roadrunner-like bird lived in China more than 100 million years ago.
A roadrunner-like bird lived in China 110 million years ago, say researchers who have analysed fossil tracks found in a quarry. The tracks are 50 million years older than any other evidence of similar birds.
Read the story here.
People are able to make themselves forget disturbing images.
People can will themselves to forget traumatic or emotional scenes, researchers have found. When the brain conducts such deletions, brain regions that process vision and emotion go quiet.
Read the story here.
Overlooked pollutants might be having a bigger effect than we thought.
Efforts to control chemical pollution may overlook thousands of toxins that concentrate as they march up the food chain, say researchers. Compounds that do not accumulate in fish can still build up in marine birds and mammals — and possibly the people that eat them, they have found.
Read the story here.
US study finds link between location and anaphylaxis.
Potentially lethal allergic reactions are much more common in the northern United States than in the south, researchers have found. What links geography and allergy is unknown, but the team behind the discovery suggests that sunlight might be a factor.
Read the story here.
This week the Nature Podcast finds water on ‘hot jupiters’, discovers how to make knock-out flies with no knock-on effects, and looks at the lucky few species that survived the Permo-Triassic mass extinction.
To SUBSCRIBE to the Nature Podcast for FREE copy and paste this URL into iTunes or your preferred media player or RSS reader:
http://www.nature.com/nature/podcast/rss/nature.xml
Astronomers enlist Internet users to unravel mysteries of galactic birth.
An experiment launching today is offering the chance to help unravel the mysteries of galaxy formation. All you need is a computer and a pair of eyes.
Read the story here.
Microbicide gel dosage prompts call for rethink.
Controversy over a ground-breaking study of an experimental HIV prevention tool has underscored the field's need to revamp its approach to clinical trials.
Read the story here.
Effects of biodiversity loss could be worse than previously thought.
Biodiversity loss could impact food production, water quality and carbon dioxide levels more than previously thought, scientists have discovered.
Read the story here.
Hopes remain for deal to free medics accused over HIV outbreak.
Libya's Supreme Court in Tripoli this morning rejected the ultimate legal appeal of five Bulgarian nurses and a Palestinian medic convicted of deliberately injecting hundreds of children with HIV in 1998.
Read more here.
Abandoned gold mine might yield secrets of life and the Universe.
The US National Science Foundation (NSF) has chosen an abandoned gold mine in South Dakota as the preferred site for a massive underground laboratory.
Read the story here.
Species able to invest in cell defence suffer less from radiation.
Birds with bright plumage have suffered most from radiation around the Chernobyl nuclear plant, scientists have discovered. Species that lay large eggs or travel long distances are also more susceptible to radiation.
Read the story here.
Wayward tyres were damaging natural corals off Florida.
An artificial reef made from tyres dumped off the coast of Florida is being dismantled, after the tyres broke their moorings and damaged natural reef in the ocean.
Read the story here.
Mouse study spots protein that generates fuel-burning tissue.
Researchers have identified a cellular switch that triggers the production of 'good' fat cells, which pump out heat and raise the body's metabolic rate. The discovery, made in mice, might one day provide a way to treat or prevent obesity in humans.
Read the story here.
Birds changed diet after humans killed shrimp eaters.
Ancient eggshell fragments show that Adélie penguins living in Antarctica switched from eating fish to krill around the time that humans began hunting seals and whales. The finding suggests that when humans removed krill-eating predators the penguins exploited the resulting shrimp surplus.
Read the story here.
Once again (see Germany thrashes Japan in RoboCup), Germans were the androids to beat in the RoboCup, held this year in Atlanta. In particular, teams from NimbRo at the University of Freiburg cleaned up in both the Kidsize and Teensize categories for humanoid robots.
For more on all categories – everything from four-legged robots to a competition to find the most agile nanobot – go here.
Game of the tournament was this thriller - an all-German Kidsize quarter-final between NimbRo and the Darmstadt Dribblers:
See also news@nature's story on the 2001 event: RoboCup 2001 boots up.
This Saturday, millions of people round the world will gather for a mega-concert series to raise awareness of climate change. News@nature.com takes a look at the event.
Al Gore is continuing his crusade to tackle climate change by hosting a 24-hour, seven-continent mega-concert. On 7 July, starting from 02:10 London time, bands will belt out songs from (in order) Sydney, Tokyo, Shanghai, Hamburg, London, Johannesburg, New York, Rio de Janeiro and, although this bit won't be live for logistical reasons, the Antarctic. Some other venues are also hosting shows, including Kyoto — home of the agreement to try to reduce greenhouse-gas emissions.
A designed alternative to lithium shows early promise.
A potential new drug for treatment of bipolar disorder (sometimes called manic depression) is being designed by researchers in Chicago and New York. The team hopes that their compound, which works as well in mice as do the currently prescribed drugs, will ultimately provide relief without the side-effects of present treatments.
Identifying drug-resistant tuberculosis is a global problem.
Researchers were surprised earlier this week when US health authorities declared that Atlanta lawyer Andrew Speaker, the American tourist recently diagnosed with a deadly strain of drug-resistant tuberculosis, doesn't have such an extreme strain after all. Despite a first test in March showing that he had a contracted an extensively drug resistant (XDR) strain before going on holiday, on 3 July the US Centers for Disease Control and Prevention (CDC) downgraded their assessment of his condition to multi-drug resistant (MDR).
It is the last day of the conference, and the sun is shining. It feels like California, but for the amethyst-throated Sunbirds and the skunky reek of buchu. Oh, and the fact that there were two kinds of beef biltong (like jerky) with lunch.
Some people loading a braai (that's a barbeque) into the back of a truck, coordinating in Afrikaans. From the grass, a student group chats in Xhosa, with its wonderful click sounds. Further off, I think that I hear Spanish.
Here are some of the best one-liners I have collected at the conference.
"Parasitism is the most popular lifestyle on earth"
--Kevin Lafferty, United States Geological Survey, talking about the importance of parasites in food webs. In the California salt marsh environment he works on with Andrew Dobson all the tiny parasites added up together would outweigh all the birds added up together.
--"Lions breed like bunnies"
Rob Slotow on one of the problems of managing lions in reserves.
--"Triage is an undeniable consequence of living in a resource-limited world."
Hugh Possingham on why people need to rationally and mathematically order conservation priorities with money in mind.
Nanoparticles show a talent for blocking immune reactions.
Soccer ball-shaped nanoparticles known as buckyballs may one day help to offer relief for allergy sufferers. Adapted buckyballs are capable of blocking the pathway mediating allergic responses in human immune cells, research has revealed.
Tools found before and after a massive eruption hint at a hardy population.
A stash of ancient tools in India hints that life carried on as usual for humans living in the fall-out of a massive volcanic eruption 74,000 years ago.
Old forests hint that the island has been icy for 450,000 years.
Scientists have drilled through two kilometres of ice in southern Greenland and retrieved DNA from the pine forest that once existed there, buzzing with prehistoric insect life. Dated to between 450,000 and 800,000 years old, the DNA is among the oldest ever found.
Samuel Wasser is a conservation biologist at the University of Washington in Seattle, and an outspoken opponent of elephant poaching. He talks to Emma Marris about his genetic methods for tracing poached ivory.
Time to start planning your 2012 orbital vacation?
Nearly a year after the successful launch of their first model inflatable space habitat, Bigelow Aerospace has launched a second, Genesis II.
More detail on the green and pro-development efforts at the conference. The decor is all native plants. The lunches are served on cardboard, with wooden cutlery. And here is more on those sedge bags: http://www.sizanacraft.co.za/contentpage.aspx?pageid=3745. Meanwhile, the café in the tent is run by Umzi Wethu, a vocational training school for "vulnerable youth" that places its graduates in the ecotourism industry—and takes them hiking.
When people talk about "the social aspects of conservation biology" I get confused. Isn't it all social? If the goal of conservation biology is to undo the havoc that humans wreak on biodiversity then isn't it all about people and societies—what they shoot, what they eat, what they burn, what they grow, what they make and spill?
Patrick Ofori-Danson Kwabena of the University of Ghana interviewed Ghanaian fishermen about hunting the rare and reserved West African manatee (Trichechus senegalensis). He found that 38 had been killed between 1998 and 2001, that the fishermen had no inkling that they needed to be conserved and that they relished the meat. Additionally, many believed that one had to have certain special powers to make a manatee kill. Compare that with their attitude towards dolphins, which in some places are—in Kwabena's words—"revered as gods". When they beach or wash up on shore, sometimes special buildings are built over the corpses.
Here are a few interesting nuggets of information from this year's posters.
According to Kathryn Williams, estimates of breeding populations of birds often undercount due to obscuring vegetation and the fact that not all birds nest at the exact same time.
Invasive species alert!. Tomás Ibarra reports the bird-eating mink (Mustela vison) have made it to formerly "pristine" Navarino Island, off of Cape Horn. In Newfoundland, invasive moose (Alces alces) are dooming the balsam fir, according to Luise Hermanutz. And menacing and ubiquitous invasive shrub Lantana (Lantana camara) shrubs are being made into furniture by Southern Indians, according to Kannan Ramesh.
A mining company has constructed an artificial island for flamingo to nest on behind Kamfers Dam, by Kimberley, South Africa. The birds like hanging out there, but whether they'll nest there successfully seems to be an open question. (more here from a South African environmental TV programme.)
Yun Fang conducted some of the first observations ever of the "nearly unknown" Sichuan Wood Owl (Strix davidi), in China, by tempting a pair to nest in a specially-built nest box. He recorded their song and watched a male and female call and beg to one another.
Paul Grobler has investigated the problem of black and blue wildebeest (Connochaetes gnou and C. taurinus), which, when brought together by the vagaries of wildlife management, have fertile hybrid offspring. This is apparently distresses managers, who want to keep the populations separate and conserved. Grobler's attempts to tell genetic lineage with microsatellite analysis of 13 loci worked on the herd level, but not on the individual.
More posters tomorrow…
Sometimes I wonder about all the studies in this field that involve walking transects—i.e. straight lines—in gorgeous country, usually noting the species that are around and other landscape variables. I am sure there's usually some reason for gathering the data, but all that adventuresome hiking in untrammeled land must make these studies more appealing.
Clint Epps takes off after the conference to Tanzania for his second season of walking transects in and between two big protected areas. He's trying to determine whether elephants hop between the two areas along the Great Ruaha River, and if they do, whether they are a good proxy for the presence of other large mammals (and therefore, perhaps, a compelling case for linking the two parks with a proper protected corridor).
Last season, armed with a machete and a GPS unit, he clocked up 400 km by walking every morning between 7:00 AM and about 2:00 PM with his wife, Lauren Gwin, and a couple of assistants. In the afternoons the team would try to find the beginning of the next transect and meet with village officials and hire a local scout. Unpleasant adventures abounded. They were stranded in one bush camp for two weeks by torrential rains; Black Mambas shot by them in the fields; and elephants got uncomfortably close to the unarmed party.
But Epps' classic transect tale is the time the truck was robbed of $1,000 worth of gear. Thieves had waited for the team to leave on their walk and smashed the windshield open. Epps repaired the windshield with duct tape and informed the locals, who told him that for $10 for their meals, five scouts would track the robbers. The scouts duly found the thieves and recovered everything, but Epps was told that he would have to transport the criminals to the police office unless he trusted them to take the bus there themselves. Of course everyone came along, so here was Epps driving a dual-cab Toyota truck with seven people in it, including the thieves, one on another's lap, their hands tied with rope, and the windshield held together with duct tape. Naturally, upon arrival, the police confiscated all the team's gear as evidence.
His talk at the conference bizarrely failed to cover these key details. He did say that signs of elephants were found across the potential corridor and that their presence was significantly correlated with how many other large mammals were around—excluding a few really big ones like buffalo and giraffe. So there could be, he said, "some utility for using elephants as a focal species."
This week the Nature Podcast zooms in on Saturn’s sponge-like moon, finds a Parkinson’s-protective protein, explores the advantages of being a mimic, and finds itself in many parallel universes at once.
To SUBSCRIBE to the Nature Podcast for FREE copy and paste this URL into iTunes or your preferred media player or RSS reader:
http://www.nature.com/nature/podcast/rss/nature.xml
Families turn to natural resources after losing key bread-winners.
The high level of HIV in sub-Saharan Africa is taking its toll on the landscape, say conservationists.
Snapshots of Hyperion show its holey nature.
Saturn's moon Hyperion looks like a sponge — it is full of holes.
Most of the criticism levelled at complementary therapies is based on the fact that a lot of them don't actually do anything. Techniques such as homeopathy and reflexology do not have a clinically proven mode of action and don't deliver any benefit beyond placebo. But at the same time, many would argue that this fact makes it perfectly acceptable for women who are desperate to conceive to use such therapies if they think they will help. After all, what's the harm?
But women who use alternative therapies may actually be damaging their chances of successfully conceiving through fertility treatment, according to Jacky Boivin of the Cardiff University. In a study of more than 800 Danish women embarking on IVF treatment, 45% of those who also took complementary therapies got pregnant within 12 months, compared with 66% for those who didn't. The implication is clear: complementary therapies, usually thought of as ultimately benign, can dent your chances of having a baby via IVF.
That's pretty striking. But the results call for closer analysis. First of all, what could the mechanism be? Boivin suggested that herbal supplements (which accounted for nearly 40% of complementary therapies in the study) might interfere with the hormone-altering drugs and other medications essential for successful IVF. Or perhaps the type of person who is interested in complementary medicine is not the type who will reliably self-administer all the right injections at exactly the right time.
But what about the most popular complementary therapy among the women in the study - reflexology? How can a glorified foot rub stop you conceiving a baby? The answer might be that women who use complementary treatments are not using them to help themselves get pregnant - they're doing it to try and cope with the psychological stress caused by their own infertility.
That leaves us with a chicken-and-egg situation. Are pregnancy rates lower because the women are using complementary therapies, or are the complementary therapies a reaction to greater stress and the need for more psychological relief? Is it a self-fulfilling prophecy?
The best way to help these women might be to tall them to ditch the holistic massages and healing crystals, and instead turn to procedures that definitely do work, such as psychological counselling to cope with the stress and depression that can be engendered by infertility. In this way, infertile women might feel less burdened by the pressure to conceive, and in so doing, boost their chances of success.
One thing I am learning here in South Africa is that the "wild" animals, especially the big mammals, may be more like those in your local zoo than you think. Is a rhino in a 4,000 hectare game reserve really roaming free? What about lions bouncing off the electrified fences at pocket-sized reserves? What about the "semi-habituated" elephants with which one can gambol around a park with, hand in trunk?
Somewhere in this uneasy middle ground are the cheetahs released by the De Wildt Wild Cheetah Project, outlined yesterday at the meeting. Most of South Africa's cheetahs live outside protected areas, often in game ranches, where each plump ungulate means big bucks to the landowner. Naturally, the landowners are not too fond of the cats, and have been known to trap and kill them. So De Wildt provides safe cage traps and more or less buys the cats off of them. They then vaccinate and tag the cats and begin a laborious months-long process of habituating them to humans in various pens for eventual release in some protected area. Why the habituation? Because un-habituated cats are invisible and invisible cats are no good for the tourists. Most of these cheetahs will be bought by people who run wildlife reserves for profit. So is the cheetah still wild? And what of the 65 cubs born to cheetahs that have been through this process?
Many large wild animals are intimately known to researchers by sight. Many are named. Many will be knocked out and either tagged, sampled or relocated during their lives. Their family trees are all worked out. Their water is provided. Their pictures have been taken so often that as the flashes pop the animals recline in the shade at ease and yawn. What defines a zoo? Is it perhaps just the size of the enclosure?
Screening embryos might do more harm than good.
Dutch researchers have questioned the effectiveness of a technique that many fertility specialists believe improves the chances of pregnancy. Preimplantation genetic screening (PGS) harms the chances of motherhood for women older than 35, they claim.
Read the story here.
Orang-utans use water to solve peanut puzzle.
Orang-utans can solve a brain-teaser that would vex many human minds, researchers have found.
For more - including videos - click here.
Conservation biology—unlike other sciences—has an explicit agenda. Its practitioners want to conserve the subjects and ecosystems they study. So when they convene they convene green. This year for the first time the SCB offered delegates the opportunity to pay a bit extra to carbon-neutralize their conference attendance. 97.3% chose to do so.
In addition, the conference bags are attractively woven of sedge by rural women. Each delegate is issued one mug to be used at all coffee breaks. The full program is on CD only. Finally, many delegates appear to be saving water and energy by wearing the same clothes to the meeting every day. Or it could be that their clothes are still flying around the world in the belly of some 767. At least one poster at the session was replaced by a sign saying "Sorry, British Airways has my poster" and I am aware of at least one portable PCR machine sitting in the airline lost and found.
Included in those sedge conference bags? A mini bottle of South African liquor and an AIDS awareness kit including a condom. Well, what are conferences for?
Technique raises hopes for infertile men.
Cloning might one day restore the fertility of men with severely low sperm counts, say researchers in the United States who have cloned mouse sperm and used it to create apparently healthy adult mice.
Read the story here.
It's expensive, there's no guarantee of success, and it seems that, for women of a certain age, it might just be better not to bother spending the money at all. IVF, at least using a woman's own eggs, should have an age limit of 44, some fertility experts are now claiming.
IVF is often used to help women the wrong side of 30 to overcome their declining fertility. But data on those receiving IVF in their 40s suggests that the rate of success diminishes effectively to zero beyond the mid-40s. Doctors led by Ronit Machtinger at Israel's Sheba Medical Center calculate that, for a sample of 154 IVF attempts carried out on women aged 45, less than 2% resulted in pregnancy, and two-thirds of pregnancies miscarried. For every successful pregnancy, almost half a million dollars had been spent by women in the sample group. Compare that with an average cost-per-pregnancy of $14,000 for women under 35.
A similar study at the University of New South Wales in Australia also concluded that 45 seems to be the cutoff point after which women should be advised not to even attempt IVF using their own eggs.
Sceptics of fertility treatment might argue that this is Mother Nature trying to tell us something. But that's not to say that older women can't become pregnant by IVF - it's just that they would be advised to use somebody else's eggs to do it. Britain's oldest mother became pregnant after receiving IVF treatment using donated eggs, and although doctors are reluctant to treat women who may not be likely to live to see their child grow up, there is currently no legal age limit for motherhood, artificial or otherwise.
Indefinite suspension follows safety lapses at Texas A&M.
The US government has halted biodefence research at Texas A&M University in College Station over safety concerns. It is the first ban on such work across an entire institution.
Read the story here.
Legal first means girl could one day give birth to her own half-sibling.
A seven-year-old girl in Canada might one day give birth to her genetic half-sibling. The girl's mother has donated her own eggs to give the child, who was born with a disease that affects her ovaries, the chance to have children of her own.
Read the story here.
One of the dominant themes of clinical research is the issue of how to preserve the fertility of young women or girls facing cancer. At the moment, the best bet seems to be freezing eggs or ovarian tissue, as sadly the rigours of chemotherapy usually cause the ovaries to shut down completely. But a new way to protect ovaries from aggressive chemotherapy may be on the horizon, says Kate Stern of the Royal Women's Hospital in Melbourne.
Stern told us about a pilot study in which she gave 18 female cancer patients a drug that temporarily and partially shuts the ovaries down, hopefully protecting them from the full onslaught of chemotherapy. The drug, called cetrorelix, calms the production of hormones that fuel ovarian function. Of 18 women given the drug, all but one had resumed normal menstruation a year after their chemotherapy, and many are hopeful that they will successfully have kids in future.
Stern's study was small and needs to be replicated in a proper clinical trial, but if it does work, the drug could offer a useful complement to egg freezing, and perhaps even supersede it entirely. After all, prevention is better than cure.
The first two plenary sessions have taken as their subject conservation in Africa. Yesterday, Yaa Ntiamoa-Baidu, a Ghanaian conservationist with positions in government, academia, and at an NGO, recounted a story from youth. She returned to her hometown after graduating from college and announced her plan to manage wildlife for a living. An old man took her to task, asking what such a career could possibly do to help their impoverished village.
And while Ntiamoa-Baidu spent the rest of her talk asking how conservationists can better demonstrate how their projects improve the lot of local people, there remained a suggestion of doubt. Perhaps not all conservation projects do improve lives.
Ntiamoa-Baidu looked at 50 random World Wildlife Fund programs in Africa. While 92% of project managers felt that their projects were helping develop the community, very few of these projects had built in any way to measure or show this. There is no data. And, according to Ntiamoa-Baidu, to convince politicians, donors and local people, you need the data.
Today, Stuart Pimm threw up a side with a series of tough questions on it. Do development efforts develop anything? Do conservation efforts conserve anything "or do we merely have conversations about it"? Does development necessarily lead to conservation ("I think we all have a sinking feeling that that might not be the case", he said)? And does conservation necessarily lead to development?
As he talked through the slide he said "I hope you are squirming uncomfortably in your seats."
This issue is not new. People have been advancing and questioning the notion that there is some real tie between conservation and development for some time. Whether it is a real relationship that holds good across contexts or just wishful thinking is the question, and one I am not prepared to answer. But in Africa, where dire poverty, HIV/AIDS and what Pimm called "inept governments" are the order of the day, one clearly cannot just waltz around saving the landscape without taking account of the people. It is their land, after all, and most of them use it every day.
In work both simple and poetically sad, Florian Werner shows how trees left behind in clearings, separated from the mass of the forest, lose their epiphytes—those plants that live on them, including ferns, orchids, and bromeliads. Werner discovered that the harsh micro-climate of an isolated tree kills off epiphytes, especially those that love moisture, while the distance from the forest reduces new seedlings and that same harsh micro-climate kills off many of the seedlings that manage to germinate.
The presentation reminded me of a work of art in the new Seattle Olympic Sculpture Park, on the waterfront downtown. The piece is by Mark Dion, the same fellow who did the excellent "Thames Dig" exhibit at the Tate in London. It is a mammoth and gorgeous 60-foot long fallen tree in an 80-foot long greenhouse. The tree has become a nurse log, and is covered with ferns, lichens, fungi and insects. But since it is in a glass box in downtown Seattle, the beautiful log will not develop as other nurse logs do in the rainforest it was helicoptered out of
Rats do unto others as they have been done to.
Rats that benefit from the charity of others are more likely to help strangers get a free meal, researchers have found.
Argentavis soared rather than flapped over Argentina.
Scientists have modelled the flight of the world's largest flying bird — a 70-kilogram ancient avian behemoth with a 7-metre wingspan. The new models show that Argentavis magnificens, which was approximately the size of a modern-day Cessna 152 light aircraft, flew by gliding rather than by flapping its giant wings in the skies above Argentina 6 million years ago.
Baby is first to be born from eggs matured and frozen in the lab.
Doctors in Canada have announced the birth of the first baby to be created from an egg that was matured in a test tube and then frozen and thawed for later use. The method offers hope for women who fall victim to sudden ovarian failure or who cannot be given drugs that promote egg maturation in the ovaries themselves.
One of the time-honoured rituals of big conferences is trawling the marketing booths in the exhibition hall looking for decent handouts (ideally edible ones). This year's top freebie takes the meeting's human reproduction theme to a quite ridiculous extreme, in the form of 'sperm drinks' (Irish cream liquer, since you asked), lovingly presented in a plastic container shaped like a wiggly egg-seeking gamete. After gingerly opening one and having a taste, several female members of the press room commented that it's not often you come to an embryology conference and find the ideal hen night accessory...
One of the pitfalls of having IVF is that you're likely to end up with more than you bargained for - even when only one embryo is implanted, the likelihood of having identical twins runs at roughly seven times that for natural births. Through some ingenious time-lapse film-making, Dianna Payne of the Mio Fertility Clinic in Yonago, Japan, has now shown us how it happens.
She set up a microscope and video camera to document the first few hours and days of a growing test-tube embryo's life. As these still images from the movei show, the embryo on the bottom left clearly features not one, but two 'inner cell masses' - the ball of cells that ultimately becomes a person. PAyne's film showed how, in some cases, the cavity that makes up the rest of the 'blastocoele' sometimes collapses and reforms, occasionally transferring some cells to the opposite side of the embryo and resulting in two cell masses, which then go on to become identical twins.
Payne's work used surplus embryos donated to research. But it has raised hopes that one day, all mothers undergoing IVF could have their embryos examined to check for this process before the embryo is transferred to the womb. Thus couples could avoid having twins... unless they really want them, of course.
News@nature.com rounds up key decisions from last week's conference on UNESCO's wonders of the world.
Louis Buckley
The first big story of the meeting is the news that doctors can now take and freeze eggs from girls as young as five, preserving their fertility in the event that they suffer childhood cancers. The treatment offers the potential to store eggs from kids facing aggressive chemotherapy that is likely to leave them sterile in later life.
Many post-pubertal women already freeze eggs, sometimes because they have cancer, in other cases simply because they want to delay having children until later in life. But the outlook for young children diagnosed with cancer was very bleak, because it was not thought that mature eggs could be obtained from such young individuals. The only alternative - freezing the entire ovarian cortex, which contains egg-producing follicles - has a much lower success rate.
But now researchers led by Ariel Revel of Hadassah University Hospital in Jerusalem have shown that follicles can be obtained from the embryonic tissue of girls as young as five. When treated with the right cocktail of hormones these can be coaxed into developing into mature eggs in the test tube - these eggs can then be frozen for later use.
Reaction to the news has been mixed - even the headline of the British sunday paper story that broke the news seemed to imply some ethical reservations. But overall the reaction has been positive - after all, despite the severity of many childhood cancers, survival rates hover between 70% and 90%, and anything that gives these kids a shot at one day becoming parents must surely be welcomed.
I saw an interesting talk in the speed sessions. These are four minute talks followed by a long interaction session, where all the presenters sit at tables and one can go up and chat with them. Excellent format, in my opinion.
The talk was on whether or not corridors make or break animal species living in forest fragments. In a lot of places in the world, what was once a forest remains only as small patches like islands surrounded by a sea of cultivated or developed land. The thinking has been that in order to keep gene flow moving between the inhabitants of these patches, corridors of trees need to be provided, like bridges between islands. The conventional wisdom that these corridors were also necessary for many birds, including the subject of the study, the small, ant-eating Australian brown treecreeper.
A team of eight spent months following treecreepers around near the town of Wagga Wagga, in both properly corridored areas as well as areas with patches and miscellaneous non-connected trees. Project leaders Erik and Veronica Doerr at the Commonwealth Scientific and Industrial Research Organization in Canberra Australia found that the birds, despite being "dumpy" fliers, in the words of Erik Doerr, moved patch to patch and made forays just as often without purpose-built corridors.
"There is a bit of corridor obsession at the moment," said Erik. While he cautions—of course—that these results are quite preliminary and of unknown generalizability, he does think that perhaps having patches that are large and relatively close together may turn out a bit more important than having the perfect, 40-metre-wide leafy green Champs Elysées between them.
Speed presentation MC Marc Hunter, strolling by Doerr's table during the meet and greet session added that "people are starting to replace the term corridor with the broader term "connectivity", which is whatever it takes to get the animal across the landscape."
Michael Hopkin is blogging at the annual meeting of the European Society of Human Reproduction and Embryology in Lyon, France, from 1-4 July. Read his updates here.
This year's conference is being held at Nelson Mandela Metropolitan University which opened in 2005 upon the merger of several institutions. The opening reception in the school's arena was crowded and fun. Introductory speeches were alternated with performances from a high school girl's choir and an energetic dance troupe which showed off African dance stylings including 1940s jive. The proceedings were marred, though, but a continual basso continuo of chit chat from the back of the room. Don't people know that those free drink tickets are a kind of payment for attentive silence during the unavoidable preliminary speeches? Hold up your end of the bargain, people.
I write from windy Port Elizabeth, South Africa, a port city on the Eastern Cape of the country. It is described by some as "the Detroit of South Africa" for its prowess in the manufacturing sector. It is also an embarkation point for those with a yen to commune with large African mammals. Many of these do their communing through the medium of a large gun.
"And you are here to stop that?" queries my cab driver, as we drive by a billboard outside the airport which advertises the reason I am here: the annual meeting of the Society for Conservation Biology.
The reason this conference is so interesting is that no, the people gathered here from the four corners of the earth are not necessarily interested in stopping that. These scientists do have an agenda, but it is not protecting the lives of individual animals but of whole ecosystems. If hunting dollars can go towards protecting and managing a piece of bio-diverse land, and if the hunting is controlled so that the hunted species are not at overall risk, great. If it keeps land clear from development for the exuberant and beautiful ungulates and felines of Africa, cool.
And there's lots of money in this kind of hunting. Trophy hunting generates $1 million in revenues for South Africa, according to the Professional Hunters' Association of South Africa (which's motto is "Conservation Through Hunting").
The aesthetics of the average conference-goer and the average hunter are clearly distinguishable variations on the theme of "I'm comfortable with dirt and the outdoors" but they rubbed shoulders on the plane in to PE (as the many call it) with ease. There are lots of reasons why the two groups would get along. They both like nature. They both want to see it preserved.
In fact, yesterday a workshop on "conservation hunting" takes a look at the growing trend and examines case studies of where it is has worked and where it hasn't. The workshop was led by Lee Foote of the University of Alberta who notes in program that "Unfortunately, neither a theoretical basis nor sufficient critical overview of [conservation hunting] has yet been advanced."
Alpha-male pheromones cause females to make brain cells.
Female mice make new brain cells when they detect a dominant male's urine, researchers have found. The discovery gives a clue as to how the chemical messages shape their receiver's taste in mates.
Read the story here.
Mouse study points to preventive treatments for cervical cancer.
Commonly used spermicides and vaginal lubricants have a marked effect on the chance of infection with human papillomavirus (HPV), the virus blamed for a large majority of cases of cervical cancer.
Read the story here.
