Donald Henderson, who has died aged 87, was the American epidemiologist in charge of the decade-long campaign to eradiate smallpox worldwide; the most significant public health initiative of the twentieth century.
The impact of the smallpox virus on the history of human development is as disastrous as it is incontestable. By the mid-eighteenth century the disease was endemic in Europe, with outbreaks affecting up to a third of the total population. For those who became ill, the mortality rate stood at around 30%. Though the arrival of effective vaccination methods precipitated a steep decline in the number of cases throughout Europe and America, attempts to replicate the effects elsewhere had been largely piecemeal until the late 1950s, when Henderson began to develop surveillance programmes for endemic diseases as part of his work with the Communicable Disease Center (CDC), stationed in Atlanta.
5,300-year-old mummy found in the Italian Alps wore clothes made from many different animals.
or the past two decades, scientists have analyzed every minute detail of Ötzi, a 5,300-year-old natural mummy found in the ice of the Italian Ötztal Alps. But one remaining mystery was the provenance of his clothing, made from leather and fur. Now, thanks to refined techniques in DNA sequencing, a team of scientists has identified how the clothing was made—and discovered something surprising about Ötzi’s domestic habits.
Ötzi lived during the Copper Age, when humans had been domesticating animals for a few thousand years, and our cutting-edge technologies included stone tools and fired pottery. From previous studies, we know that Ötzi was likely murdered by an arrow and a blow to the head. We also know he suffered from arthritis, and he ate a meal of deer and berries before he died.
The team’s new findings, published in Nature Scientific Reports, are as much a demonstration of DNA sequencing wizardry as they are about ancient fashion. It’s incredibly difficult to get genetic material out of tanned hides, because they’ve generally been scraped, heated, and exposed to fatty acids. Plus, the hides and furs themselves had disintegrated. But the researchers used several methods for extracting DNA from the hides that made up Ötzi’s shoelace, hat, loincloth, coats, leggings, and quiver. First they compared the strands of DNA they did find with other mapped genomes to identify species. Then the researchers targeted very small, specific regions in the DNA for reconstruction to learn more about the animals’ relationships with today’s domestic breeds.
Telltale red circles of ancient Chinese practice said to boost blood flow, rejuvenate muscles
Eyebrows raised in Rio over the weekend when Olympic athletes like swimmer Michael Phelps started showing up with circular purple bruises on different parts of their bodies.
These bruises are caused by “cupping” — an ancient Chinese medical technique that may — or may not — stimulate muscles and increase blood flow, possibly relieving pain. The practice has become newly trendy among athletes and celebrities, experts said.
Cupping gets its name from special round cups that are placed on the skin over targeted muscle groups. These cups create suction against the skin, either by being heated or through use of an air pump.
The cosmetic result is apparent.
“When you put enough suction anywhere on the body, you get a bruise. You get that with a hickey,” said Dr. Brent Bauer, director of the Mayo Clinic Complementary and Integrative Medicine Program in Rochester, Minn. “You’re basically rupturing some of the tiny blood vessels.”
Interest in cupping has grown since cupping marks started showing up on celebrities within the past couple of years, said Dr. Houman Danesh, director of integrative pain management at Mount Sinai Hospital in New York City.
176,500 years ago, long before modern humans left Africa for the Eurasian continent, a band of Neanderthals conducted an elaborate ritual deep inside Bruniquel Cave in a region we know today as southern France. The Neanderthal group wrested hundreds of stalagmites from the floor of the cave to build elaborate circular structures, their work illuminated only by firelight. Discovered by archaeologists in the 1990s, the cave system is so large that many of its great treasures are hidden far from its entrance, which suggests it was thoroughly explored and probably inhabited for some period of time. This new part of the cave, analyzed only recently, adds to our understanding of Neanderthal social life
The Neanderthal structure was mostly undisturbed for tens of thousands of years with the exception of a few hibernating bears. Recounting their discovery in Nature, a group of archaeologists say there is no question that the structures were created deliberately by humans, especially because there is evidence that the stalagmites were wrenched from the cave floor and stacked in circular patterns.
The first animal to appear on Earth was very likely the simple sea sponge.
New genetic analyses led by MIT researchers confirm that sea sponges are the source of a curious molecule found in rocks that are 640 million years old. These rocks significantly predate the Cambrian explosion — the period in which most animal groups took over the planet, 540 million years ago — suggesting that sea sponges may have been the first animals to inhabit the Earth.
“We brought together paleontological and genetic evidence to make a pretty strong case that this really is a molecular fossil of sponges,” said David Gold, a postdoc in MIT’s Department of Earth, Atmospheric and Planetary Sciences (EAPS). “This is some of the oldest evidence for animal life.”
The results are published today in the Proceedings of the National Academy of Sciences. Gold is the lead author on the paper, along with senior author and EAPS Professor Roger Summons.
Scientists have mapped the genome of bedbugs in New York City, then traced fragments of the nefarious pests’ DNA through the subway system.
In the grubby recesses of hundreds of stations, they discovered surprising genetic diversity among the bloodsucking creatures. The next step is to figure out how the information can be put to good use, such as to develop better insecticides or blood thinners.
But these goals will take further medical research.
For now, the focus is on two main players in New York life: the subway and bedbugs.
Scientists already have found that genetic traces of bedbugs in northern Manhattan are more closely related to those in the island’s southern part, while there are bigger variations between the Upper East Side and Upper West Side.
Since his discovery in 1991, Ötzi the “Iceman” — an intact, naturally mummified man believed to have lived in the Italian Alps approximately 5,300 years ago — has captured the international imagination and provided a tantalizing glimpse into life during the Copper Age.
Now, a new research project, which analyzed the genetic composition of bacteria in the Iceman’s stomach, is giving scientists insight into not only the Iceman’s personal life, but the history of human geography at large.
The scientists, who published their study in the journal Science on Thursday, focused on a type of common bacteria called Helicobacter pylori, or H. pylori. Found in about two thirds of the world’s population, according to the National Institutes of Health, it usually inhabits the stomach and is capable of causing infections that can lead to ulcers or even stomach cancer.
In one of the 20th century’s most disastrous collisions of political ideology and science, the Russian botanist Trofim Lysenko steered the USSR’s agricultural research policies to deemphasize the deterministic concepts of Mendelian inheritance. Instead, Lysenko was committed to the idea that, within the space of a single generation, the environment could alter the phenotype of future generations, an idea that is now often (imprecisely) referred to as “Lamarckian” inheritance. In Lysenko’s view, Mendelian inheritance, along with Darwinian evolution, emphasizes competition, whereas he believed that biology was based on cooperation, and that hard work in one generation should rapidly lead to the betterment of the species.
Lysenko was among the most infamous purveyors of the idea that the environment experienced by an organism could influence the phenotype in future generations, and he was rightly denounced as a charlatan because he falsified results in pursuit of his goal. However, the scientific community has discovered over the past few decades that the idea that acquired characters can be inherited may not be completely off the mark. It turns out that epigenetic marks, information not encoded in the genome’s sequence, do respond to environmental conditions within an organism’s lifetime, and recent evidence suggests that such information may be inherited.
These findings have helped motivate modern research into the oft-discredited study of transgenerational effects of the environment. Researchers are now beginning to understand the mechanisms of epigenetic inheritance and to generate evidence for the idea that the experiences of an ancestral population can influence future generations.