Dogs were domesticated between 9,000 and 34,000 years ago, suggesting the earliest dogs most likely arose when humans were still hunting and gathering – before the advent of agriculture around 10,000 years ago, according to an analysis of individual genomes of modern dogs and gray wolves.
An international team of researchers, who published their report in PLoS Genetics Jan. 16, studied genomes of three gray wolves, one each from China, Croatia and Israel – all areas thought to be possible geographic centers of dog domestication. They also studied dog genomes from an African basenji and an Australian dingo; both breeds come from places with no history of wolves, where recent mixing with wolves could not have occurred.
Their findings revealed the three wolves were more closely related to each other than to any of the dogs. Likewise, the two dog genomes and a third boxer genome resembled each other more closely than the wolves. This suggests that modern dogs and gray wolves represent sister branches on an evolutionary tree descending from an older, common ancestor. The results contrast with previous theories that speculated dogs evolved from one of the sampled populations of gray wolves…
Computer methods for analyzing complete genome sequences developed by Ilan Gronau, the paper’s second author and a postdoctoral associate in Siepel’s lab, played a key role in the collaboration. Gronau’s computer program, called G-PhoCS (Generalized Phylogenetic Coalescent Sampler), was previously applied with success in a 2011 Nature Genetics study of early human history and demographics.
In this case, G-PhoCS provided a detailed picture of the demographic changes that occurred during the divergence of dogs from wolves. The analysis revealed that domestication led to sizable pruning in population of early dogs and wolves. Dogs suffered a sixteenfold cut in population size as they diverged from an early wolf ancestor. Gray wolves also experienced sharp drops in population, suggesting that the genetic diversity among both species’ common ancestors was larger than represented by dogs and modern wolves. In addition, there was considerable gene flow between dogs and wolves after domestication. Accounting for gene flow was a major challenge in the analysis, and Gronau’s research on this topic proved valuable in obtaining an accurate model of canid demography.
Fascinating stuff. I love science even more than I love wolves and dogs. Helluva combination.
Forget those clumsy, complicated, home cholesterol-testing devices. Cornell engineers have created the Smartphone Cholesterol Application for Rapid Diagnostics, or “smartCARD,” which employs your smartphone’s camera to read your cholesterol level.
“Smartphones have the potential to address health issues by eliminating the need for specialized equipment,” said David Erickson, Cornell associate professor of mechanical engineering and senior author on a new peer-reviewed study. Thanks to advanced, sophisticated camera technology, Erickson and his colleagues have created a smartphone accessory that optically detects biomarkers in a drop of blood, sweat or saliva. The new application then discerns the results using color analysis…
Currently, the test measures total cholesterol. The Erickson lab is working to break out those numbers in LDL (“bad” cholesterol), HDL (“good” cholesterol) and triglyceride measurements. The lab is also working on detecting vitamin D levels, and has previously demonstrated smartphone tests for periodontitis and sweat electrolyte levels.
“By 2016, there will be an estimated 260 million smartphones in use in the United States. Smartphones are ubiquitous,” said Erickson, adding that although smartCARD is ready to be brought to market immediately, he is optimistic that it will have even more its advanced capabilities in less than a year. “Mobil health is increasing at an incredible rate,” he concluded…
Health selfies will end up meaning as much or more in 3rd World and developing regions of the world. Local health technicians can setup and oversee affordable procedures in countries where the growth of mobile phones far exceeds either telephone networks or readily available health clinics.
Graduate student Pinshane Huang and Professor David Muller
At just a molecule thick, it’s a new record: The world’s thinnest sheet of glass, a serendipitous discovery by scientists at Cornell and Germany’s University of Ulm, is recorded for posterity in the Guinness Book of World Records.
The “pane” of glass, so impossibly thin that its individual silicon and oxygen atoms are clearly visible via electron microscopy, was identified in the lab of David A. Muller, professor of applied and engineering physics and director of the Kavli Institute at Cornell for Nanoscale Science…
Just two atoms in thickness, making it literally two-dimensional, the glass was an accidental discovery, Muller said. The scientists had been making graphene, a two-dimensional sheet of carbon atoms in a chicken wire crystal formation, on copper foils in a quartz furnace. They noticed some “muck” on the graphene, and upon further inspection, found it to be composed of the elements of everyday glass – silicon and oxygen.
They concluded that an air leak had caused the copper to react with the quartz, also made of silicon and oxygen. This produced the glass layer on the would-be pure graphene.
Besides its sheer novelty, Muller continued, the work answers an 80-year-old question about the fundamental structure of glass. Scientists, with no way to directly see it, had struggled to understand it: It behaves like a solid but was thought to look more like a liquid.
Now, the Cornell scientists have produced a picture of individual atoms of glass, and they found it strikingly resembles a diagram drawn in 1932 by W.H. Zachariasen – a longstanding theoretical representation of the arrangement of atoms in glass.
“This is the work that, when I look back at my career, I will be most proud of,” Muller said. “It’s the first time that anyone has been able to see the arrangement of atoms in a glass.”
Politicians and economists have a habit of characterizing unintended consequences as inherently negative. Scientists find them inherently – interesting.
Anticipatory robot holding open a fridge door
What’s better than as robot bartender that can pour you a beer? How about a robot waiter that can see you need a refill and comes over to pour you another one. Hema S. Koppula, a Cornell graduate student in computer science, and Ashutosh Saxena, an assistant professor of computer science are working at Cornell’s Personal Robotics Lab on just such a robot. Using a PR-2 robot, they’ve programmed it to not only carry out everyday tasks, but to anticipate human behavior and adjust its actions.
Robots are the neat freaks of the technology world. They like things to be tidy, orderly and predictable, meaning they work best in places like laboratories and factories where everything can be controlled and where it’s easy to predict what’s going to happen next. When a robot moves out of its comfort zone into our imperfect world, it can run into difficulties. Even something as seemingly simple as noticing that someone’s glass is empty and topping it up requires a lot of observation and planning on the robot’s part.
The Cornell anticipatory robot avoids embarrassing spills and other accidents by using its Microsoft Kinect scanner to build up a 3D map of the objects present and then calculating how they might be used based on the action currently being performed by the person…
The robot is also able to put various subactivities together in different combinations to form models of larger activities that it can use to anticipate the movements of people in different situations. The models it builds are general enough to take into account the fact that different people will perform the same activity slightly differently.
Truly useful example of technology serving the core needs of human culture.
Professor Martha Mutschler and executive chef Steve Miller
Cornell researchers have developed new mild onions that will have chefs crying – tears of joy. Twelve years in development and with a couple years of testing to go, researchers say it will be just a few years before the mild locally grown onions are available to the public.
“These onions have a longer shelf life and still produce huge flavors; I see them as being a consumer’s dream,” said Steve Miller, Cornell Dining senior executive chef, who with a Wegmans supermarket executive chef has tested about a dozen of the experimental onion hybrids.
In general, current mild onions are watery and soft due to low sugar content (called low brix), which leads to a short shelf life and makes them mushy when cooked. Longer-lasting pungent onions are higher in sugar and caramelize when cooked, but reducing their bite requires more cooking, which also softens them.
The new Cornell onions “have the initial aroma and flavor of a mild onion, but they have a lot less water,” said Mike Washburn, executive chef at Wegmans. As result, they have a longer shelf life and stay crisper and intact when cooked in soup or chili or when grilled.
Martha Mutschler, professor of plant breeding and genetics, developed the mild onion lines and used the results of the chefs’ tests to inform selection of the three new hybrids of mild onions that were in expanded trials last year.
…The doubled haploid mild onion lines are unique in that they are totally inbred: “The seeds from each double haploid plant will produce identical plants” that are extremely uniform for any traits, said Earle.
…Mutschler is coordinating three phases of the project: …to develop hybrids adapted to New York state; …working with New York onion growers to field test the experimental hybrids; …working with executive chefs for culinary tests to determine potential marketing of the new onions. These phases are interrelated as seed companies and growers need to know consumer interest in the product before they take the risk of investing in producing a new crop.
Bravo! I am forever characterized as relying on my loyalty to Mediterranean recipes which invariably “start by taking an onion…”
Professor Bonassar and the matrix for an ear
Cornell bioengineers and physicians have created an artificial ear that looks and acts like a natural ear, giving new hope to thousands of children born with a congenital deformity called microtia.
In a study published online…in PLOS One, Cornell biomedical engineers and Weill Cornell Medical College physicians described how 3-D printing and injectable gels made of living cells can fashion ears that are practically identical to a human ear. Over a three-month period, these flexible ears grew cartilage to replace the collagen that was used to mold them.
“This is such a win-win for both medicine and basic science, demonstrating what we can achieve when we work together,” said co-lead author Lawrence Bonassar, associate professor of biomedical engineering.
The novel ear may be the solution reconstructive surgeons have long wished for to help children born with ear deformity, said co-lead author Dr. Jason Spector, director of the Laboratory for Bioregenerative Medicine and Surgery and associate professor of plastic surgery at Weill Cornell.
“A bioengineered ear replacement like this would also help individuals who have lost part or all of their external ear in an accident or from cancer,” Spector said…
The process is also fast, Bonassar added: “It takes half a day to design the mold, a day or so to print it, 30 minutes to inject the gel, and we can remove the ear 15 minutes later. We trim the ear and then let it culture for several days in nourishing cell culture media before it is implanted…”
Bonassar and Spector have been collaborating on bioengineered human replacement parts since 2007. Bonassar has also worked with Weill Cornell neurological surgeon Dr. Roger Härtl on bioengineered disc replacements using some of the same techniques demonstrated in the PLOS One study.
The researchers specifically work on replacement human structures that are primarily made of cartilage — joints, trachea, spine, nose — because cartilage does not need to be vascularized with a blood supply in order to survive.
They are now looking at ways to expand populations of human ear cartilage cells in the laboratory so that these cells can be used in the mold, instead of cow cartilage.
“Using human cells, specifically those from the same patient, would reduce any possibility of rejection,” Spector said.
Bravo! There is no shortage of projects awaiting these pioneers. A solid merger of science and technological advancements.
They believe they are about 3 years away from first human transplant experiments.
It’ll look like hundreds of postage stamps fluttering toward Earth — each an independent satellite transmitting a signal unique to the person who helped send it to space.
A Cornell-based project called KickSat is set to launch more than 200 of these tiny satellites, nicknamed “sprites,” into low-Earth orbit as part of a routine NASA-administered mission in 2013 to the International Space Station. And unlike traditional, big government space exploration, KickSat is truly a launch by the people.
Several years ago…Zac Manchester…now a graduate student in aerospace engineering, dreamt up the idea of crowd-sourced, personal space exploration. He and Ryan Zhou…and Justin Atchison…designed and built a prototype spacecraft that fits in the palm of the hand and costs just a few hundred dollars to make. The sprites are a type of micro-satellite called a “ChipSat…”
Manchester’s goal, he says in his blog about the mission, “is to bring down the huge cost of spaceflight, allowing anyone from a curious high school student or basement tinkerer to a professional scientist to explore what has until now been the exclusive realm of governments and large companies. By shrinking the spacecraft, we can fit more into a single launch slot and split the costs many ways. I want to make it easy enough and affordable enough for anyone to explore space.”
Sprites are the size of a cracker but are outfitted with solar cells, a radio transceiver and a microcontroller (tiny computer). KickSat, which is the name of the sprites’ launching unit, is a CubeSat, a standardized cubic satellite the size of a loaf of bread, frequently used in space research.
Using Kickstarter.com to find sponsors for the mission, Manchester raised nearly $75,000 as more than 300 people sponsored a sprite that will transmit an identifying signal, such as the initials of the donor. In 2013, about 250 sprites will be sent into space. One person, who donated $10,000, Manchester added, will get to “push the big red button” on the day of the launch.
A delightful dedication to citizen science. A special tradition centuries-old.
While trying to figure out what makes certain beverages cloudy, Cornell researchers made the startling discovery that certain chemicals in green tea — and perhaps red wine — react with saliva in ways that can alter how we perceive flavors.
Specifically, regular consumption of the polyphenol-rich drinks can boost astringent sensations and our sensitivity to acids, reports Karl Siebert, professor of food science, Cornell University. Siebert also discovered that we all have varying levels of polyphenols already stored in our systems.
Siebert, who worked for 18 years in a brewery before becoming an academic, stumbled upon the finding while studying the relationship between polyphenols — chemical compounds found in plants — and protein chains in such drinks as beer and apple juice…
Siebert’s group discovered the strong effect of pH on haze formation, peaking at a pH level near 4. More acidic beverages like grape juice don’t get as cloudy. Higher pHs also lead to less haze.
He then measured the polyphenol levels in saliva of people on days before, during and after they consumed several cups of green tea. This showed that saliva normally contains polyphenols, and there are large differences among individuals. Regular red wine and green tea drinkers had the highest levels. Drinking green tea was shown to elevate the saliva polyphenol levels.
“I would expect that red wine drinking would also, but we didn’t demonstrate this,” Siebert said…
“It appears that there is a metabolic pool of polyphenol that is influenced by dietary habits, and that the salivary polyphenol level influences perception of astringency caused by acids,” Siebert said.
RTFA. I’ll watch for an easily accessible copy of the original research – and the work that follows on from this study. Siebert thinks it may explain the “French paradox” – how they have a relatively low incidence of heart disease, despite their diet rich in saturated fats.
For the Cornell University Autonomous Underwater Vehicle team, months of meticulous testing, refining and retesting has paid off: With a flawless 11.5-minute run through a complex course of underwater tasks in the final round, the team’s autonomous submarine beat the competition and earned first place in the 12th annual Association for Unmanned Vehicle Systems International/Office of Naval Research (AUVSI/ONR) competition in San Diego.
The win earned the team $10,000.
The Cornell undergraduates — 32 in all, 12 of whom traveled to the competition — competed against 29 other teams in the five-day competition.