Marked Prairie Dog — The chin of an anesthetized prairie dog in Wind Cave National Park, South Dakota is marked before the animal is released back into the wild.
Over 30 organizations and agencies are testing a USGS-developed oral vaccine to prevent the spread of plague in prairie dogs. If successful, the sylvatic plague vaccine could help protect endangered black-footed ferrets in the western U.S. because the ferrets rely on prairie dogs for food.
A veterinarian tags each trapped prairie dog and takes hair, whisker, and blood samples before scientists release the animals. Chin markings help scientists determine whether certain trapped prairie dogs had been previously tested. If markings are present on a trapped animal, that animal is immediately released without further testing. Photo credit: Marisa Lubeck, USGS.
Good Reasons for "Believing" in God - Dan Dennett, AAI 2007
Dan Dennett's talk at the AAI 2007 Conference in Washington, D.C. He is presented with the 2007 Richard Dawkins award at the introduction. https://www.youtube.com/watch?v=BvJZQwy9dvE
According to a study published in the journal Biological Reviews, non-avian dinosaurs might have survived the impact of a large bolide about 66 million years ago if it had happened a few million years earlier or later.
This image shows two individuals of Qianzhousaurus sinensis and a small feathered dinosaur called Nankangia. Image credit: Chuang Zhao.
“There has long been intense scientific debate about the cause of the dinosaur extinction,” said Dr Richard Butler from the University of Birmingham, who is a co-author on the study.
“Although our research suggests that dinosaur communities were particularly vulnerable at the time the asteroid hit, there is nothing to suggest that dinosaurs were doomed to extinction. Without that asteroid, the dinosaurs would probably still be here, and we very probably would not.”
“The dinosaurs were victims of colossal bad luck,” added Dr Steve Brusatte of the University of Edinburgh, the lead author on the study.
“Not only did a giant asteroid strike, but it happened at the worst possible time, when their ecosystems were vulnerable. Our new findings help clarify one of the enduring mysteries of science.”
Dr Brusatte and his colleagues studied an updated catalogue of dinosaur fossils, mostly from North America, to create a picture of how dinosaurs changed over the few million years before the asteroid hit.
The team found that in the few million years before a large bolide (comet or asteroid) struck what is now Mexico, Earth was experiencing environmental upheaval. This included extensive volcanic activity, changing sea levels and varying temperatures.
At this time, the dinosaurs’ food chain was weakened by a lack of diversity among the large herbivorous dinosaurs on which others preyed. This was probably because of changes in the environment and climate.
This created a perfect storm of events in which non-avian dinosaurs were vulnerable and unlikely to survive the aftermath of the asteroid strike.
As food chains collapsed, this would have wiped out the dinosaur kingdom one species after another.
The only dinosaurs to survive were those who could fly, which evolved to become the birds of today.
The scientists said if the asteroid had struck a few million years earlier, when the range of dinosaur species was more diverse and food chains were more robust, or later, when new species had time to evolve, then they very likely would have survived. _____ Stephen L. Brusatte et al. The extinction of the dinosaurs. Biological Reviews, published online July 28, 2014; doi: 10.1111/brv.12128
Reading Climate Change in the Leaves
An ecologist records nature's color signals to understand the feedback between plants and a changing climate.
Andrew Richardson installs instruments 115 feet up in the Harvard Forest.
Courtesy Donald Aubrecht
A silver station wagon loaded with climbing gear, computers, electrical wiring and a few scientists from Harvard University stops near a stand of pine and oak trees in the Harvard Forest, about 70 miles west of campus. Physiological ecologist Andrew Richardson, leader of this expedition, slips from the driver’s seat and grabs gear to ascend a metal tower among the trees. Its peak affords
Richardson a clear view of his living laboratory: the forest canopy.
Above the treetops, he checks a cluster of instruments that analyze the lush canopy as a collection of numbers: the amount of carbon being inhaled from the atmosphere, the concentration of water vapor in the air and the precise mix of hues the leaves exhibit.
Different pigments serve different functions: Green chlorophyll, which dominates during the growing season, absorbs light energy for photosynthesis, the conversion of carbon and water to sugar. In the shortening days of autumn, red anthocyanins and yellow carotenoids take over to help protect leaves against light damage.
To document this subtle seasonal color change, a webcam atop the tower snaps high-resolution images of the canopy every 30 minutes from dawn to dusk and uploads them to an online database.
During the past decade, Richardson has spearheaded an effort to install more than 80 such cameras at sites across North America, from the arctic tundra near northern Alaska’s Toolik Lake to the tropical grasslands surrounding Hawaii’s towering Mauna Kea.
This PhenoCam Network amasses thousands of photos per day. Over time, Richardson hopes the resulting trove of color data will help scientists understand — and better predict — how ecosystems like the Harvard Forest respond to changes in the climate.
Fall colors in the Harvard Forest on any given day (Oct. 9 in this case) vary from year to year, depending on temperature and rainfall.
Courtesy of Andrew Richardson/PhenoCam Network (3)
A Pulsating Palette
Over the course of millennia, white snow cover, vibrant autumn foliage and bright bursts of green have punctuated the rhythmic cycles of winter frosts, spring showers and long, warm summer days. Animals have evolved to be in sync with seasonal change: They bring young into the world just as nutritious green sprouts emerge in spring, and molt to blend in with winter whites and summer green-browns. It’s an intricate dance scientists refer to as phenology.
Richardson’s efforts to decipher this color code began in the 1990s, shortly after his return from an eight-month trek in Canada’s Yukon Territory. “It was the vegetation, the transition from forest to tundra and how the colors changed through the seasons that really captivated me,” he recalls.
Richardson had recently abandoned pursuit of a Ph.D. in economics at MIT and found himself in awe of nature’s colorful clockwork — so much so that he redirected his studies.
Richardson enrolled in Yale University’s forestry program in 1996 and a few years later threw himself into a project lopping off balsam fir and red spruce branches in the White Mountains. He measured how much light the needles reflected in different wavelengths. This is an indicator of stress and “a very precise way of measuring color,” he explains.
Richardson showed that needles in the harsh, resource-poor high altitudes invested in stress-protection pigments to cope with wind, cold and blazing sun.
Reading the Leaves
“Phenology is really sensitive to weather,” Richardson explains. “If it’s a cold spring, leaves will come out later. If it’s a warm spring, that will happen earlier.”
Forests in the United States absorb and store more than 750 million metric tons of carbon dioxide each year, or more than 10 percent of national carbon emissions. Warmer temperatures triggering earlier green sprouts could produce a longer growing season in some places and more photosynthesis — and thus more carbon uptake. But early growth followed by frost or drought could damage fragile sprouts and reduce the amount of carbon that certain plants are able to absorb. Some species also respond to warming by fast-forwarding through their life cycles, narrowing the window for photosynthesis and carbon uptake.
Nature’s color palette already shows effects of climate change. Along the East Coast, where the “green wave” of spring leaves sprouting from maples, oaks and poplars historically has rolled from Miami to Maine in 75 days, atmospheric scientists with Princeton University predict the wave could take just 59 days by the end of the century. In parts of New England, fall colors arrive a few days later than they did 20 years ago, and the reds are more muted as autumn temperatures in the region warm.
But scientists don’t know what new rhythms will arise across different regions — whether bursts of green will be brighter but shorter-lasting, for example, or more muted but longer-lasting. Nor do they know what such changes mean for the food web; for life-cycle events like migration, breeding and nesting; for the amount of moisture that trees will suck from the soil; or for the amount of carbon dioxide stored by plants.
That’s what Richardson hopes to tease out. “As we build up a big archive — warm years, cold years, wet years and dry years — we can use the data to develop models of how weather and phenology are related,” he says. These models can then be mapped against climate forecasts to predict how phenology could shift in the future, painting a picture of landscapes in a world of warmer temperatures, altered precipitation and humidity, and changes in cloud cover. “We want to use phenology as a biological indicator of the impacts of climate change on ecosystems,” Richardson says.
Richardson climbs a tower in New Hampshire’s White Mountains to repair a wireless network.
Courtesy Mariah Carbone
Cameras Rolling
Webcams offer a cheap way to monitor foliage at a local scale across a broad geographic range. “These pictures give you this permanent record,” Richardson says. “I can see what it was like on any day. I can go back to other years and compare, and tell you how things are different between those two years.”
Scientists have used satellite-mounted sensors to indirectly measure vegetative growth around the globe for decades. But cloud cover and other atmospheric clutter often muddle the data. A study published in Nature in February suggests that previous models based on satellite data have overestimated greenness during dry seasons in the Amazon rainforest. Shadows, which shorten over the course of the tropical dry season, produce an optical illusion: Leaves reflect more light in the infrared spectrum, even as their actual greenness declines.
Researchers need ground-level measurements like those of the PhenoCam Network to validate
remotely gathered information and refine the algorithms used to evaluate it. Richardson’s work complements field observations by researchers like Harvard ecologist John O’Keefe, who visited the same trees in the Harvard Forest every few days for more than 20 years, starting in the 1990s, to track the opening of buds in springtime and autumn leaf coloration. Last year Richardson’s team analyzed O’Keefe’s historic data set and found that most local tree species will likely display fall colors for longer durations and at higher intensity in coming years.
A decade and a half after Richardson’s shift to ecology, he has come to see leaf color the way an economist might view a financial statement. “It tells you a lot about the physiology of the leaf,” he says.
Eighty-two feet up the tower, Richardson emerges above the dark understory of the Harvard Forest to feel a flush of sunlight and a flick of breeze on his face. “The views from the top are fantastic,” he says, “and this motivates a lot of what I do.” His methodical quest to decode the phenological rainbow has a way of propelling itself forward. As Aldo Leopold, who doggedly recorded seasonal signposts in Wisconsin in the 1930s and ’40s, once wrote: “Keeping records enhances the pleasure of the search, and the chance of finding order and meaning in these events.”
[This article originally appeared in print as "Cracking the Climate Color Code."]
Early Cretaceous Bloodsucking Bugs Found in China
July 26, 2014 | by Janet Fang
Photo credit: Flexicorpus acutirostratus / Y. Yao et al., Current Biology 2014
Fossilized blood-feeding bugs have been discovered in early Cretaceous sediments in China. That means at least one lineage of bloodsuckers was around 30 million years earlier than we thought. They may have even fed from dinosaurs. According to the study published in Current Biology this week, the fossils represent two new species, and they’re the earliest evidence of blood-feeding “true bugs.”
True bugs (order Hemiptera) have a mouthpart designed for sucking fluids, called the proboscis. But unlike proboscis-wielding butterflies or honeybees, true bugs can’t roll up their mouthparts. Modern true bugs include nasty bed bugs. As annoying and ubiquitous as they seem, blood-feeders (also called hematophages) are relatively uncommon among modern insects. They’re mostly found in just four orders: lice, fleas, true flies (including mosquitoes), and true bugs. The latter three have been documented prior to the Cenozoic.
It’s been hard to tell hematophages apart from their non-blood-feeding relatives in the patchy insect fossil record. Until now, only one hematophagous true bug, Quasicimex eilapinastes, has been described, from mid-Cretaceous amber in Myanmar, about 100 million years ago.
Working in the early Cretaceous Yixian Formation of Northeastern China, a team led by Yunzhi Yao and Dong Ren of Capital Normal University in Beijing studied nearly 400 insects. In seven true bug specimens, they looked specifically for geochemical signals of iron, which indicates blood meals. By combining those findings with results with morphological and taphonomic (fossilization) data, the team placed three of the bloodsuckers into two new genera within a new family, Torirostratidae.
The other fossilized true bugs belonged to phytophagous (plant eating) families or predaceous families, which include assassin bugs who would liquefy the insides of their prey, before drinking them. Their iron concentrations were much lower.
They named one of the new true bugs Flexicorpus acutirostratus. That’s Latin “flexi” for “soft” and “corpus” for “body.” The species name is taken from Latin “acuti” for “sharp” and “rostratus” for “beaked.” It's less than 10 millimeters long, and here are some cool pictures:
They’re naming the other one, which is over 12 millimeters long, Torirostratus pilosus. That’s Latin “torosus” for “bulges” and “rostratus” for “beaked” (again). The species name is comes from Latin “pilosus,” which refers to its dense setae (stiff bristles).
One of the bugs appears to have died immediately following a blood meal, which may have been taken from a mammal, bird, or dinosaur, though the researchers can’t be sure. (Insert Jurassic Park joke here, bonus points for True Blood.)
Images: Y. Yao et al., Current Biology 2014
Read more at http://www.iflscience.com/plants-and-animals/early-cretaceous-bloodsucking-bugs-found-china#mzQvUAVVY8ffihKI.99
Refreshing Our Hearts -- With Thich Nhat Hanh
Published on Mar 26, 2014
Enjoy this video stream from our friend Thich Nhat Hanh which we originally broadcast live in October of 2013, from the Paramount Theater in Oakland, CA.
Cleaning Up Polluting Mines With Plants--Plants That Then Turn Into Precious Metals
One enterprising scientist thinks we're close to creating a whole new, much greener mining industry.
Nothing grows here at Walker Ridge. Oaks, pines, and wildflowers stop abruptly at the edges of a huge swath of bare earth. The dead zone--tinged an uneasy shade of green--stretches almost as far as the eye can see in one direction, down a slope that feeds directly into a watershed. Piles of dirt, scraps of rust-eaten metal, and a few crumbling bricks seem the only signs left of what was once a Gold Rush-era mercury mine. They’re not.
In Dylan Burge’s vision of the Walker Ridge site, mining operations are booming again. Thousands of rows of deeply green, compact plants are thriving in the toxic soil, reaching for sunlight that filters through fabric tarps stretched overhead. Downhill (just below glinting banks of solar panels), metal-contaminated effluent from the old mine is being captured and piped back up to the plants, watering some rows while filling hydroponics for others. The mercury problem is under control, trucks are rolling off the site, and no one’s spending $7 million. In fact, people are making money. That's because, as Burge sees the future possibilities, the world’s first loads of truly “green,” sustainable metals--mostly nickel from this site, plus a little gold--are headed for market.
Burge, 34, is a botany curator at the California Academy of Sciences and an expert in hyperaccumulators--plants that attract and suck up huge quantities of metals by releasing ion-attracting compounds from their roots. Found generally in metal-rich serpentine soils (like the kind most hard rock mines, like Walker Ridge, sit on), each species has protein pathways that seem “tuned” for a particular type of metal. Gold, nickel, copper, zinc, cobalt, aluminum, manganese, even some rare earth elements, they’re are all on the menu.
The idea of “phytomining”--using these plants in commercial mining operations-- isn’t new; mining companies actually funded much of the early research, a wave that gained momentum in the mid-1970s before petering out about 20 years ago. “Things got pretty quiet after that,” says Burge, “but not because phytomining didn’t work. It was because the yields weren’t profitable enough to be interesting. The technology wasn’t there, and the science wasn’t there.” He’s got a two-part plan to fix that.
Burge works with Streptanthus polygaloides, a small, flowering herb native to California that’s also the third most powerful nickel hyperaccumulator in the world, capable of sucking up as much as 2% of its dry bodyweight. In the Walker Ridge hypothetical, these plants are harvested up to six times a year and mixed into a live slurry. Microbes break the slurry down--creating sellable carbon-neutral ethanol as a byproduct--and metal production begins with the material that’s left. During the process, massive amounts of hydrolysis occur, allowing hydrogen to be captured, stored, and converted into electricity that helps power the plant. “And all this could be done right now,” says Burge. “No waiting. All you need is a botanist, an abandoned mine, and a tech startup that’s good at scalable solutions.”
Dylan refers to these mines as “point-source problems” (small sites with huge environmental impact), but monetizing their cleanup by creating a consumer market for sustainable metals could have benefits far beyond safer, healthier local ecosystems. Metals worldwide are cheap not because they’re unlimited or easy to get at, but because we pass on the vast environmental and social costs of mining them to other countries. If American consumers were to start asking where the metal in their devices, cars, and wedding rings come from--and paying for the kind that doesn’t leave destruction in its wake--it could pave the way for a new kind of mining.
Burge is already at work on one key to that future: unraveling the genetic secrets of hyperaccumulators. Last month, he became the first person known to have sequenced the full genome of a hyperaccumulator--of 24 of them, actually--and somewhere in the resulting terabytes of data, he expects to find the gene (or suite of genes) that gives Streptanthus its metal-mining abilities. With that discovery should come the Holy Grail of phytomining: the potential to create larger, more efficient hyperaccumulators.
“If you make it your goal as a scientist to affect the world in your lifetime,” says Burge, “you’re almost guaranteed to fail. But every once in a while,” he adds, “it’s possible to get lucky.”
Profits from a Streptanthus metal harvest will never be big enough to get the commercial mining industry excited about becoming farmers. But splice the gene for hyperaccumulation into something with significant biomass--something like corn, for example--and one of the dirtiest, most dangerous, most destructive industries in the world might start paying attention again.
