|Sue is something of a celebrity among dinosaurs, being the best-preserved T. rex fossil ever found. But in truth, the gender of dinosaurs is rarely, if ever, known. A study in 2005 first laid claim to a new way to sex dinosaurs using a distinctive bone formation. Now paleontologists in China have found that ancient birds also had this structure, confirming that birds and dinos shared similar gender divisions and reproductive habits.
Researchers excavated the 125-million-year old birds’ feathers, organs and bones from petrified lake-bottom mud in northeastern China. These birds, called Confuciusornis sanctus, were buried by the hundreds following catastrophic volcanic eruptions in the Mesozoic era.
You are what you eat—that’s true even after your bones have spent 200 years buried in the dirt. A new study using old bones from 18th century British sailors confirmed the naval diet: lots of biscuits, more protein than the average landlubber, and the same damn things sailors ate for the previous 200 years.
The Victualing Board actually kept meticulous records of a sailor’s official rations: 1 lb of bread and 1 gallon of beer per day (!), plus 1 lb of pork twice a week, 2 lbs of beef twice a week, or butter and cheese the other three days. But when the going got tough out in the middle of watery nowhere, did sailors actually get their rations? Yes, it seems, based on an analysis of nitrogen isotopes extracted from the bones of 80 sailors. The elevated levels of nitrogen suggested that sailors did get as much beef and pork as the Victualing Board recorded. And despite being at sea, they didn’t seem to eat much fish.
A team of doctors in Glasgow, Scotland, have begun using ultrasound to help heal patients’ broken bones, claiming the technique can reduce recovery time by up to 40 percent with especially bad fractures. Developed in the 1950s by physicians in the same city, ultrasound is widely used in sonograms to produce images of developing fetuses. Sonograms are made by emitting sound waves into the body and recording the reflected patterns. To heal fractures, sound is emitted at a slightly different frequency and stimulates the development and activity of osteoblasts, which lay down new bone.
Lucy loved the land, new research suggests. A study in this week’s edition of the journal Science puts forth a foot bone from the early hominid Australopithecus afarensis (Lucy’s kind) as evidence that this species was built for walking—meaning human ancestors could have been striding around on ground level for most of their lives by 3.2 million years ago.
Scientists already knew that A. afarensis could walk on two feet but were unsure whether the creatures climbed and grasped tree branches as well, much like their own ancestor species and modern nonhuman apes. The fourth metatarsal … shows that A. afarensis moved around more like modern humans. “Now that we know Lucy and her relatives had arches in their feet, this affects much of what we know about them, from where they lived to what they ate and how they avoided predators,” said Carol Ward. [The Guardian]
The bone in question comes from Ethiopia, home to many significant hominid finds. And though it is just a small sample, that arched shape in the foot bone suggests Australopithecus had rigid feet, and may not have been much better at climbing trees than you or I.
Arches were an important part of our evolution into humans, because they make climbing trees much harder. The arches on the inside of the foot, nearer to the big toe, serve as a shock absorber when we plant our feet back on the ground. All other living primates have feet made for grasping and bending to hang onto tree branches and their young, more like our hands than our feet. [LiveScience]
Researchers studying Xenicibis xympithecus now believe the bird’s peculiar wing structure, which confused them for decades, was ideally formed to be used as a club.
Xenicibis is a large, extinct, flightless ibis. It was discovered by Storrs Olson from the Smithsonian Institution, who found some partial remains in a Jamaican cave in 1977. When Olson eventually saw the bird’s wing bones, he was baffled. They were so “utterly strange” that he thought the animal must have been suffering from some inexplicable disease.
Since then, Olson has found more remains including an almost complete skeleton. Now, he and his partner Nicholas Longrich from Yale University, have a very different view of the wing. They think it was a club. Weapons like clubs and bats have large weighted ends to deliver heavy impacts, and long handles to increase the speed of the swing. That’s exactly what you see in Xenicibis’s wing.
For more about the these birds and their weapons of mass pummeling (and why they may have evolved this way), check out the rest of the post at Not Exactly Rocket Science.
Discoblog: I Can’t Fly! Birds Lost Their Aerial Abilities Multiple Times
Not Exactly Rocket Science: First birds were poor fliers – flaps would have buckled Archaeopteryx feathers
DISCOVER: Tuxedo Junction—speaking of weird flightless birds, read Mary Roach’s feature on the migration of Patagonian penguins
Image: Proceedings of the Royal Society B
After two years of work developing new guidelines to tell us how much vitamin D and calcium is enough, the Institute of Medicine released its report this week with the basic message: Relax, you’re all doing pretty well.
Yet confusion still reigns in headlines about the report, as there are several different facets to the new standards (and the reaction to them). The new report also seem to contradict earlier, alarming studies that found vitamin D deficiencies in most Americans. So, what’s going on?
Most people are doing just fine
IOM looked at both Vitamin D and calcium intake for different age groups, and slogged through hundreds of studies of the levels of those nutrients versus health. The only group that was found deficient was adolescent girls, whom the researchers said should intake a little bit more calcium.
The panel said its findings challenged the notion that, when it comes to dietary nutrients, “more is better” — a belief that has inspired a multibillion-dollar market for dietary supplements in the United States. Americans spent $1.2 billion last year on calcium supplements and $430 million on pills containing vitamin D, according to the Nutrition Business Journal. [Los Angeles Times]
Ohio State oncologist Steven K. Clinton, a coauthor of the report, says most people have enough variety in their normal diet to get adequate amounts of both nutrients.
New findings? Not convincing enough
The reason that gigantic supplement market exists is that a number of studies have suggested vitamin D—found in some foods but mostly produced in your skin by the action of ultraviolet radiation—could help to prevent diseases like cancer, heart disease, diabetes, and more. But in its meta-review of vitamin D studies, IOM wasn’t convinced. Its report reinforced the traditional wisdom that vitamin D is crucial for skeletal health, but wouldn’t go further in determining healthy levels.
MIT may have found the answer to astronauts’ bone loss in space: really, really tight suits.
The new suit — the Gravity Loading Countermeasure Skinsuit — aims to mimic the effect of gravity on the body. The tight catsuit wouldn’t look out of place in a superhero comic. It features stirrups that hook over the feet and it is purposefully cut too short so that it stretches over the body when worn, pulling the wearer’s shoulders down. The aim is to make sure the legs experience greater force than the torso, just as they do on Earth. [Wired UK]
The Man Vehicle Lab at MIT developed the skin-tight apparel. The researchers are testing it out aboard parabolic flights—those airplane rides that simulate weightlessness—to see if it succeeds in mitigating the harmful health effects of life in zero-G.
Don’t be fooled by those sinister fangs: For saber-toothed cats, much of the killing power was concentrated in the front limbs.
The long canine teeth that gave the extinct cat its name are an unmistakable feature, protruding from the snarling faces of models in natural history museums everywhere. But while those fangs were deadly, their great length also made them delicate and liable to break if the cat’s prey jostled and writhed in an attempt to escape. Researcher Julie Meachen-Samuels had an idea how such a precarious killing device could have evolved: The cats had incredibly strong front limbs to hold down prey while they used their saber teeth to cut them up.
For a study that appears in the journal PLoS One, the team x-rayed the bones of many saber-toothed cats (Smilodon fatalis), and compared them to a variety of modern-day cats. According to Meachen-Samuels:
Behold La conversione di San Paolo (The Conversion of St. Paul), one of the masterworks of Caravaggio. The Italian artist of the Baroque era was famous for the chiaroscuro shading—dramatic contrasts of light and dark—evident in this conversion scene. But he was also renowned for living hard and dying young. Four centuries after his death, Italian researchers say they’ve found his bones, and they might know what actually killed him: the lead in his paints.
First, the researchers had to find his remains. Caravaggio died in 1610 in the Tuscan town of Porto Ercole, but his remains were whereabouts unknown until a researcher claimed to turn up a death certificate in 2001 pointing to the crypts there. The bones the scientists found there matched a man aged 38 to 40 (Caravaggio’s age range at his death) and dated to his era. And the DNA matched combinations found in people from the painter’s hometown and sharing his original surname, Merisi or Merisio.
“There can’t be the scientific certainty because when one works on ancient DNA, it is degraded,” Giorgio Gruppioni, an anthropologist on the team, told The Associated Press. “But only in one set of bones did we find all the elements necessary for it to be Caravaggio’s — age, period in which he died, gender, height.” The group says there is an 85 percent probability they are right, though team leader Silvano Vinceti says that is conservative. “We are being cautious,” he said. “As a historian I can say we have found the remains… All evidence concurs” [AP].
As study after study suggests that wine might have health benefits, beer tends to get the short end of the stick. But food scientist and beer lover Charles Bamforth wasn’t going to take that lying down, saying: “The wine guys have stolen the moral high ground. I resent the stance that people take that wine is better. It’s not” [Discovery News]. To prove it, he studied the silicon content of beers from around the country, and in a study in the Journal of the Science of Food and Agriculture, found that beer could be a good source of the substance in your diet.
Bamforth found that the beer’s silicon content ranged from 6.4 milligrams per liter to 56.5 milligrams per liter, with an average of about 30 milligrams. Since two pints of beer are just about equal to one liter, drinking two beers at happy hour could provide 30 milligrams of silicon. And while there is no official recommendation for daily silicon uptake, the researchers say, in the United States, individuals consume between 20 and 50 mg of silicon each day [LiveScience]. Light lagers and non-alcoholic beers not only lack flavor, they showed the lowest silicon content in Bamforth’s study. The ultra-hoppy India pale ales came in first.