Category Archives: Biology

Rejecting the Solutrean hypothesis: the first peoples in the Americas were not from Europe

A recent Canadian documentary promoted a fringe idea in American archaeology that’s both scientifically wrong and racist

Last month’s release of The Ice Bridge, an episode in the Canadian Broadcasting Corporation series The Nature of Things has once again revived public discussion of a controversial idea about how the Americas were peopled known as the “Solutrean hypothesis”. This idea suggests a European origin for the peoples who made the Clovis tools, the first recognized stone tool tradition in the Americas. As I was one of the experts appearing on the documentary, I want to share my thoughts about it and why I see the ideas portrayed within as unsettling, unwise, and scientifically implausible.

First, in addition to the scientific problems with the Solutrean hypothesis which I’ll discuss shortly, it’s important to note that it has overt political and cultural implications in denying that Native Americans are the only indigenous peoples of the continents. The notion that the ancestors of Native Americans were not the first or only people on the continent has great popularity among white nationalists, who see it as a means of denying Native Americans an ancestral claim on their land. Indeed, although this particular iteration is new, the idea behind the Solutrean hypothesis is part of a long tradition of Europeans trying to insert themselves into American prehistory; justifying colonialism by claiming that Native Americans were not capable of creating the diverse and sophisticated material culture of the Americas. Unfortunately, the producers of the documentary deliberately chose not to address this issue head-on, nor did they include any critical perspectives from indigenous peoples. While supporting the agenda of white nationalists was not the intent of the producers or of the scientists involved, it would have been appropriate for the documentary to take a stand against it, and I and many archaeologists are disappointed that they did not.

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Source: gad

DIY faecal transplants carry risks including HIV and hepatitis, warn experts

Faecal transplants have been used in medical settings to tackle superbugs, but following YouTube videos at home is too risky, say researchers

Concerns have been raised about the growing trend for DIY faecal transplants, with experts fearing such attempts could put individuals at an increased risk of HIV and hepatitis as well as conditions ranging from Parkinson’s and multiple sclerosis to obesity and sleep disorders.

The transfer of faeces from one human to another has gained attention as a growing number of studies have suggested links between microbes in the gut and a host of health problems, from autoimmune diseases to anxiety.

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Source: gad

Hot stuff: the thermal cameras giving us a new way of seeing our bodies

How do our bodies regulate themselves – and is it even true that we have a single body temperature? New technology will tell us

I’m one of those people who always feels cold. Maybe it’s my upbringing in the chilly north, or maybe it’s down the quirks of my own physiology, but I’m reliably found next to the fire, hiding from draughts that no-one else had noticed, or buried inside enough jumpers to stock a small shop. At the other end of the scale, when everyone else is sweating buckets, I’m basking smugly because I’m finally at a comfortable temperature.

Like most of us, my attitude towards my body temperature is similar to Goldilocks’ attitude to porridge – it’s either too cold, too hot, or 37C, which is just right. But I’ve rarely considered the fascinating details of exactly how our bodies regulate their temperature, and whether it’s even true that we have a single body temperature anyway.

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Source: gad

'Paramedic ants' observed treating injured comrades

The social insects have been seen cleaning wounds and possibly administering antibiotics to prevent infection

When the battle is done the victors head home, their march broken only to gather the wounded, who are hauled back to base for life-saving treatment.

Not a heroic scene from the second world war, but the daily grind for African Matabele ants, which leave their nests in the hundreds to launch raids on feeding termites – and risk life and limb in the process.

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Source: gad

Tracing the tangled tracks of humankind's evolutionary journey

The path from ape to modern human is not a linear one. Hannah Devlin looks at what we know – and what might be next for our species

Let’s go back to the beginning. When did we and our ape cousins part ways?
Scientists are still working on an exact date – or even a date to within a million years. Like many of the big questions in human evolution, the answer itself has evolved over the past few decades as new discoveries, techniques and technology have provided fresh insights.

Genetics has proved one of the most powerful tools for time-stamping the split with our closest living relative, the chimpanzee. When our complete genomes were compared in 2005, the two species were found to share 98% of their DNA. The differences hold important clues to how long our lineages have been diverging. By estimating the rate at which new genetic mutations are acquired over generations, scientists can use the genetic differences as a “molecular clock” to give a rough idea of when the split occurred. Most calculations suggest it was between four to eight million years ago.

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Source: gad

Talking animals: we aren’t the only species capable of speech …

Ongoing studies show that some mammals and birds can mimic the sound of the human voice

Research published last month proved that orca, or killer, whales have the ability to mimic the complexities of human speech. Josep Call, professor in evolutionary origins of mind at the University of St Andrews, was a co-author of the study. He said: “I think here we have the first evidence that killer whales may be learning sounds by vocal imitation.”

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Source: gadt

Safety blunders expose lab staff to potentially lethal diseases in UK

Exclusive: breaches investigated involve dengue virus, anthrax and other deadly pathogens

Safety breaches at UK labs that handle harmful bacteria, viruses and fungi have spread infections to staff and exposed others to potentially lethal diseases, the Guardian has learned.

The Health and Safety Executive (HSE) has investigated a series of mistakes over the past two years that led to scientists falling ill at specialist labs run by hospitals, private companies, and even Public Health England (PHE), the government agency which exists to protect and improve the nation’s health and wellbeing.

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Source: gad

'He's one of us': modern neighbours welcome Cheddar Man

DNA tests suggesting man who lived 10,000 years ago had dark skin and blue eyes cause a stir

Rachel Andrews, who was tending the bar at the Black Dog Saloon, a wild west-themed cider pub at the foot of Cheddar Gorge, was not going to have a word said against the village’s most famous former resident.

“We’re very proud of Cheddar Man,” she said. “There’s a really good, strong community spirit around here. We all look after each other and he’s definitely one of us.”

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Source: gad

First modern Britons had 'dark to black' skin, Cheddar Man DNA analysis reveals

The genome of Cheddar Man, who lived 10,000 years ago, suggests that he had blue eyes, dark skin and dark curly hair

The first modern Britons, who lived about 10,000 years ago, had “dark to black” skin, a groundbreaking DNA analysis of Britain’s oldest complete skeleton has revealed.

The fossil, known as Cheddar Man, was unearthed more than a century ago in Gough’s Cave in Somerset. Intense speculation has built up around Cheddar Man’s origins and appearance because he lived shortly after the first settlers crossed from continental Europe to Britain at the end of the last ice age. People of white British ancestry alive today are descendants of this population.

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Source: gad

Gone fishin': decorator crabs use other species as fishing rods, study reveals

A researcher’s diving holiday lead to a startling discovery of never-before-seen behaviour: crabs using hydrozoans as fishing hooks

Every night as the sun goes down, on the coral reefs of the Red Sea small, delicate and slightly fuzzy-looking crabs work their way through the maze of coral. They take up stations atop the corals’ outermost structures, exposing themselves to the current in the plankton-rich waters. These are decorator crabs, of the genus Achaeus, known for their peculiar habit of covering themselves with an array of invertebrates, including delicate hydrozoans: multi-headed creatures with tiny tentacled polyps that feed on plankton.

In a recent paper published in the journal Marine Biodiversity, Dr Joan J Soto Àngel, from the University of Valencia, suggests that the crabs are not only benefitting from the camouflage and defence the hydroids provide, but are also “fishing”, using their covering of hydrozoan polyps as the hooks.

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Source: gad