GAINESVILLE, Fla. — Vividly colorful giant clams officially called tridacnids decorate many an upscale aquarium. But now experts say they boast an exterior beauty that masks an ugly truth: their potential for carrying foreign diseases.

In findings that may impact the reef clam industry as well as international trade, a University of Florida veterinary pathologist recently discovered Perkinsus olseni, an internationally reportable foreign pathogen, in aquacultured clams imported from Vietnam.

While not believed to be a threat to human health or other reef aquarium species, the pathogen’s presence concerns scientists as well as aquaculture industry representatives and points out the largely unregulated environment in which the importation of aquacultured reef clams from Asia occurs.

“I had 30 clams in my lab as part of a student research project,” said Barbara Sheppard, a clinical associate professor of pathology at the UF College of Veterinary Medicine. “Then they started looking sickly, and within four months, all of them were dead.”

As a pathologist, Sheppard was intrigued. She began investigating the cause of death by freezing tissues, putting them into formalin and conducting histopathology and DNA tests in her laboratory. Her findings, which will appear in an upcoming issue of Diseases of Aquatic Organisms, showed the presence of Perkinsus olseni along with a new species of Perkinsus that has yet to be characterized.

“This is an important finding,” said Ralph Elston, president of AquaTechnics, a Carlsborg, Wash.-based company that provides veterinary, laboratory and environmental assessment services to the shellfish industry. “It indicates the potential risk of the spread of animal disease when health monitoring is not in place to control such risks.”

Elston added that further research is needed to evaluate the distribution of previously unknown species of Perkinsus in Florida.

Giant clams are the largest bivalves in the world. Their range stretches across the Indo-Pacific region from the eastern coast of Africa in the west to the South Pacific in the east, according to the United Nations Environment Program’s World Conservation Monitoring Center. These clams represent an increasingly large proportion of the live invertebrates imported to become aquarium specimens. As a result of overexploitation, all species of giant clams are included in the Convention on International Trade in Endangered Species of Wild Fauna and Flora, an international agreement between governments that aims to ensure that international trade in specimens of wild animals and plants does not threaten their survival.

Based on CITES data from 1993-2001, Vietnam has dominated the export of live giant clams since 1998. The United States and Europe are the main importers, and captive bred, or aquacultured, clams represent only about a third of the nearly 1 million tridacnids traded worldwide.

Sheppard is now collaborating with the Virginia Institute of Marine Sciences, the Maryland Department of Agriculture and Anita Wright, a Perkinsus researcher and associate professor at UF, to further characterize the new exotic species of Perkinsus that Sheppard discovered in her clam colony.

“This is not a zoonotic disease, transmissible to people,” Sheppard said. “No one is going to get sick from this, as far as we know. The problem here is economic and international trade. We know that Perkinsus is a pathogen of aquatic shellfish, and the reason it is so important is that it makes animals very vulnerable to dying when the weather gets hot or when they get stressed in some other way.”

She added that a major pathogen known as Perkinsus marinus is already associated with the depletion of major oyster stocks on the Atlantic coast.

“It’s indigenous; you can’t avoid it, and we know that particular pathogen is already economically devastating to our shellfish industries,” Sheppard said. “They don’t want this Pacific version of Perkinsus (olseni) to be transported here.”

Although the infected clams were found in Florida, tridacnids are imported and distributed to hobbyists throughout the United States. Sheppard’s findings suggest that almost certainly clams infected with Perkinsus olseni and the new Perkinsus species have made their way into consumer aquariums throughout the United States, she said.

“This is a great example of why you should never release an aquarium animal anywhere, under any circumstances,” said Ruth Francis-Floyd, director of UF’s Aquatic Animal Health Program. Aquarium owners seeking an aquatic veterinarian may reference the AquaVets Web site at www.aquavetmed.info/.

The ornamental aquarium trade operates globally with very few restrictions to transport product as quickly as possible, said Craig Watson, director of UF’s Tropical Aquaculture Laboratory in Ruskin.

“There are probably 3,000 species involved, and no one species has the value to justify the cost of a quarantine facility big enough to handle everything,” Watson said.

Members of the clam aquaculture industry as well as the oyster industry are aware of the recent Perkinsus olseni findings and are trying to respond, he added.

Watson said he is working with Florida aquaculture representatives who “really want to do the right thing” and added that his laboratory has proposed a voluntary protocol involving testing and quarantine procedures.

“The cost of doing this, however, is significant,” he said. “The ultimate goal would be to start a Perkinsus-free aquaculture industry in the United States where baby clams that have never been exposed to the disease are produced.”

Reported this month in the online edition of the Journal of Proteome Research, the advance could one day lead to earlier detection and improved treatment of some types of cancer as well as other diseases.

“With many diseases, the problem has been that we really don’t know what to look for,” said Weihong Tan, a professor of chemistry and the lead author of the paper. “What we’ve done is create a technique to identify the biomarkers despite that limitation.”

Doctors often diagnose cancer and other diseases based on the appearance of a tumor or a patient’s symptoms. While such traditional methods can be effective, they sometimes identify a disease only after it is established. For example, clinicians may get tipped off to the presence of lung cancer — which kills more people than any other type of cancer — based on visible images of a tumor that appear on radiological exams of a patient’s lungs.

Because earlier detection typically improves outcomes, doctors would like to spot disease at the molecular level, before it grows or spreads and manifests itself in more obvious and harmful ways. Given that diseased cells’ molecular structures differ from those of healthy ones, that approach should be possible, and researchers have had some success finding such “biomarkers” using antibodies, Tan said. But despite years of research, biomarkers for most diseases remain elusive or unreliable, he said.

His group turned to “aptamers,” single-strand chains of DNA or RNA that recognize and bind to target protein molecules, as a new tool. His paper reports the first-ever successful use of the aptamers to discover a molecular biomarker — in this case, one for leukemia.

Tan said his group used cell-SELEX, a process his group developed and patented.

Researchers create trillions of different varieties of aptamers in a solution. They then immerse cells known to carry the sought-after disease in the solution. After an incubation period, they rinse the cells.

The vast majority of the aptamers wash away, but those with stronger molecular affinity for the diseased cells remain. The researchers repeat the process several times, eventually shrinking the pool of aptamers to as few as 10 to 25 very strongly attached aptamers — those most closely associated with the diseased cells. Analysis then reveals these aptamers’ molecular structure, as well as the molecular structure of the cells’ biomarkers they bind to.

“As long as the molecules in question are expressed in a substantially different way on diseased and normal cells, they can be identified,” Tan said.

Rebecca Sutphen, associate professor and director of the Genetic Counseling & Testing Service at the H. Lee Moffitt Cancer Center & Research Institute in Tampa, said improved diagnosis may not be the only application of the research.

“The opportunity to identify cancer cell-specific biomarkers and potentially detect small numbers of cancer cells has many potential clinical applications, including disease detection, better imaging of tumors and even potential application for stem cells,” she said.

Other biomarkers have been found for leukemia, but none is particularly reliable, Tan said. Tan and his colleagues reported using aptamers to recognize cancer cells in a 2006 paper in the Proceedings of the National Academy of Sciences. Tan said the latest paper advances that work by revealing the target biomarkers the selected aptamers recognize, Tan said. These targets will form a molecular foundation in understanding diseases, he said.

“In 2006, we did not know what the aptamer recognized on the cancer cell surface,” he said. “In this current work, we report discovering these biomarkers, which then form the molecular foundation for us to understand the cancer and to prepare different molecular tools for molecular medicine.”

Tan said the research is particularly promising because aptamers are relatively easy and inexpensive to manufacture compared with antibodies. “This offers the potential for wider application,” he said, adding that aptamers could one day be used not only to detect disease, but also to ferry therapeutic agents to diseased cells.

The research was funded in part with two grants from the National Institutes of Health. It was also funded with two grants from Florida’s Bankhead-Coley Cancer Research Program and one grant from the State of Florida Center of Excellence in Bio/nano sensors.

The paper’s co-authors are Dihua Shangguan, Zehui Cao, Ling Meng, Prabodhika Mallikaratchy, Kwame Sefah, Hui Wang and Ying Li.

Confirming a decades-old prediction, the physicists with the CLEO collaboration say they observed a rare and extremely short-lived subatomic particle with the unusual name of “charmed-strange meson” decay into a proton and anti-neutron.

Detection of the event, which the collaboration made public Sunday at http://arxiv.org/, was attributed to John Yelton, a physicist at the University of Florida, one of many institutions that are part of the CLEO collaboration.

“It’s the sort of thing that, for many years, people have known should happen,” Yelton said. “What we have done is show that it does, and how often.”

The Cornell Electron Storage Ring accelerator, or CESR, collides electrons with positrons at energies ranging from 3 to 5 billion electron volts — producing many short-lived, elementary and rare particles of interest to physicists. CLEO, the large experimental detector designed to detect the accelerator collisions, is a joint project of nearly two dozen institutions in the U.S., Canada and England.

Among the products of the CESR collisions are the charmed-strange mesons, which exist for less than one-trillionth of a second before decaying into other more stable particles. Although charmed mesons have been studied for 30 years, no one had ever observed one decaying into a proton or neutron, as theory had predicted. This is notable because about 10 percent of all the collisions in the accelerator produce protons and neutrons.

Yelton did not detect the anti-neutron directly but rather inferred its presence from data on energy and momentum of other particles.

All told, he found 13 instances of charmed-strange mesons decaying into protons and anti-neutrons, retrieving and identifying those events from data on millions and millions of different collisions and their aftermaths.

Yelton based his analysis on techniques developed at Syracuse University for the detection of two other types of rare subatomic particles, a muon and invisible neutrino.

“Professor Yelton did an extraordinary job of applying our techniques to a new area and extracted an excellent result in record time,” said Sheldon Stone, co-spokesman for CLEO and the physics professor at Syracuse who, with graduate student Nabil Meena, first developed the techniques. “This is what working together in an experiment is all about.”

David Asner, a physicist with Carleton University and CLEO’s other co-spokesperson, said the observation will contribute much to theoretical work on particle decay.

“Observation of these rare decays has the promise of increasing our understanding of the underlying mechanisms of how the world is put together,” he said.

When CLEO was first started in 1979, CESR was among the highest energy accelerators operating at the time. More recent accelerators, such as the Tevatron at Fermilab in Chicago and the soon-to-be-completed Large Hadron Collider in Switzerland, operate at far higher energies. Most public attention is focused on research in these colliders — research aimed at, among other things, observing the so-called “God” particle, the Higgs boson.

Yelton said the latest result shows there remains much to be learned from collisions at lower energy in lower energy colliders. “It highlights the fact that there is still physics to be done at lower energy accelerators,” he said.

The CLEO collaboration has also submitted a paper on the discovery to the journal Physics Review Letters.

The National Science Foundation funded the bulk of the CESR hardware and operations. The research is funded by the NSF, the U.S. Department of Energy, the Natural Sciences and Engineering Research Council of Canada and the U.K. Science and Technology Facilities Council.

So concludes a group of researchers, including a scientist in the University of Florida Emerging Pathogens Institute, who spent three years producing the first spatial map of global malaria risk in four decades.

The Malaria Atlas Project’s findings appear today in the online edition of the open-access medical journal, PLoS Medicine.

The Malaria Atlas Project, or MAP, found that 2.37 billion people were at risk of contracting malaria from Plasmodium faciparum, the most deadly malaria parasite for humans transmitted through the bites of infected Anopheles mosquitoes. Of that number, about 1 billion people live under a much lower risk of infection than was assumed under the previous historical maps. The lower than expected risk extends across Central and South America, Asia and even parts of Africa, the continent where malaria kills the vast majority of its victims and where risk has historically been classified as universally high.

“This gives some hope of pursuing malaria elimination because the prevalence isn’t as universally high as many people suppose,” said David Smith, a UF associate professor of zoology and a co-author of the paper. “It’s reasonable to think we can reduce or interrupt transmission in many places, but the prospects for success will improve if we make plans that are based on good information about malaria’s distribution.”

The MAP effort, a collaboration between Oxford University and the Kenyan Medical Research Institute, compiled information from national health statistics, tourist travel advisories, climate, mosquito vectors and surveys of malaria infection in nearly 5,000 communities and 87 countries. The project also incorporated information about how climatic conditions affect mosquito life cycles, and thus the likelihood of active transmission.

“One of my contributions was to help standardize prevalence estimates,” Smith said.

The new map is important in part because it offers hope that malaria could be eliminated in certain areas using currently available tools, such as bed nets treated with insecticide that kills mosquitoes, the researchers said. It will also help donors and international agencies target investments in control measures where they are most likely to achieve the biggest gains.

More than 500 million cases of malaria are reported annually. Of those afflicted, about one million die; 80 percent of them are children in sub-Saharan Africa.

The research was funded by the Wellcome Trust. In accordance with the trust’s philosophy on open access, all the data and techniques tapped in the MAP are freely accessible via the project’s Web site at http://www.map.ox.ac.uk.

“Making data and maps more accessible on the worldwide web is a large part of the MAP’s philosophy of getting the science accessed, critiqued and used by a much wider range of users,” said the lead author of the paper, Carlos Guerra, of the University of Oxford.

The paper can be found at http://medicine.plosjournals.org/perlserv/?request=get-document&doi=10.1371/journal.pmed.0050038.

At least, that’s what is suggested in a paper published today in the journal Human Brain Mapping authored by a group of professors in advertising and communication and neuroscience at the University of Florida.

The seven researchers used sophisticated brain-scanning technology to record how subjects’ brains responded to television advertisements, while simultaneously collecting the subjects’ reported impressions of the ads. By comparing the two resulting data sets, they say, they pinned down specific locations in the brain as the seat of many familiar emotions that ripple throughout it. The feat is another step toward gauging how people feel directly through functional magnetic resonance imaging, or fMRI, and other brain-scanning technology — without relying on what they claim to be feeling, the researchers say.

“We are getting to the heart of the matter by really showing this process in the brain, and how it works,” said Jon Morris, a professor of advertising and communications and lead author of the article. “We feel that this can be used to find out what people really feel about something, whether an advertisement or any other stimulus.”

Using MRI or fMRI — the former creates internal images of the brain, while the latter tracks blood flow within the brain — to test consumers’ responses to advertisements or other stimuli is not new. But according to the study, much of the previous research has found that, for example, responses to pleasant or unpleasant stimuli occurred throughout many regions of the brain, rather than in one specific location. As a result, the technique seemed of limited usefulness: Analysts could gauge only general response activity, not specific emotions.

“There was no real key happiness center, no key sad center, no key love center,” Morris said. “What you got was brain activity, in general.”

The UF team used an elaborate experimental system, currently under consideration for a patent, to try to narrow the search.

Because metallic or magnetic material can cause fMRI machines to malfunction, no television or sound equipment was allowed in the cylinder-like fMRI machines into which people are inserted. As a result, the researchers deployed a series of projections and mirrors to allow subjects to watch commercials. Sound reached them via tiny plastic pipes, similar to headphones once common on airplanes, rather than wires.

The 12 subjects also had hand-held devices that enabled them to report their feelings via a system called “Attitude Self Assessment Manikins” a version of the UF-developed Self-Assessment Manikin, or “SAM.” The “AdSAM” system lets viewers describe how they are feeling and the strength of those feelings by clicking on projections of people-like icons, a process that Morris characterized as more direct than translating feelings into words. Morris uses the AdSAM system in his work as a consultant to advertisers.

Researchers showed the subjects three television commercials advertising Coke, Evian and Gatorade, respectively, as well as an anti-fur commercial and an ad promoting teaching. To guard against preconditioned response, all the ads were at least 10 years old.

The researchers compared the activity in the subjects’ brains as recorded by the fMRI machines to their reported responses on the AdSAM system. With several of the ads, they found the fMRI data and response converged on two of three measures — pleasure-displeasure and excitement-calm. Under the AdSAM system, these “bipolar dimensions” — as well as a third, dominance-submissiveness — form the foundation for more specific emotions.

Where the researchers compared the AdSAM data on pleasure-displeasure and excitement-calm to the fMRI data, they found simultaneous spikes in four different and highly localized areas of the brain. According to the article, the findings suggest “that human emotions are multidimensional, and that self-report techniques — correspond to a specific task but different functional regions of the brain.”

Morris said the results are preliminary, but that follow-up studies could allow researchers to hone in on people’s feelings with great specificity. That would be attractive to advertisers for obvious reasons, but psychologists might also find the techniques useful.

“Back in the 1950s, three psychologists found that all emotions could be measured in three dimensions,” Morris said. “Now we have learned that this may be more than a method for reporting emotion. It may actually reflect the way creatures on this planet function — possibly exposing a direct link to predicting behavior.”

Furthermore, the New World was colonized by approximately 1,000 to 5,000 people — a substantially higher number than the 100 or fewer individuals of previous estimates.

The developments, to be reported by University of Florida Genetics Institute scientists in Wednesday’s (Feb. 13) edition of PloS ONE, help shape understanding of how the Americas came to be populated — not through a single expansion event that is put forth in most theories, but in three distinct stages separated by thousands of generations.

“Our model makes for a more interesting, complex scenario than the idea that humans diverged from Asians and expanded into the New World in a single event,” said Connie Mulligan, an associate professor of anthropology at the College of Liberal Arts and Sciences and assistant director of the UF Genetics Institute. “If you think about it, these people didn’t know they were going to a new world. They were moving out of Asia and finally reached a landmass that was exposed because of lower sea levels during the last glacial maximum, but two major glaciers blocked their progress into the New World. So they basically stayed put for about 20,000 years. It wasn’t paradise, but they survived. When the North American ice sheets started to melt and a passage into the New World opened, we think they left Beringia to go to a better place.”

UF scientists analyzed DNA sequences from Native American, New World and Asian populations with the understanding that modern DNA is forged by an accumulation of events in the distant past, and merged their findings with data from existing archaeological, geological and paleoecological studies.

The result is a unified, interdisciplinary theory of the “peopling” of the New World, which shows a gradual migration and expansion of people from Asia through Siberia and into Beringia starting about 40,000 years ago; a long waiting period in Beringia where the population size remained relatively stable; and finally a rapid expansion into North America through Alaska or Canada about 15,000 years ago.

“This was the raw material, the original genetic source for all of the Americas,” said Michael Miyamoto, a professor and associate chairman of zoology in UF’s College of Liberal Arts and Sciences. “You can think of the people as a distinct group blocked by glaciers to the east. They had already been west, and had no reason to go back. They had entered this waiting stage and for 20,000 years, generations were passing and genetic differences were accumulating. By looking at the kinds and frequencies of these mutations in modern populations, we can get an idea of when the mutations arose and how many people were around to carry them.”

Working with mitochondrial DNA — passed exclusively from mothers to their children — and nuclear DNA, which contains genes from both parents, UF scientists essentially added genetic information to what had been known about the archaeology, changes in climate and sea level, and geology of Beringia.

The result is a detailed scenario for the timing and scale of the initial migration to the Americas, more comparable to an exhaustive video picture rather than a single snapshot in time.

“Their technique of reading population history by using coalescence rates to analyze genetic data is very impressive — innovative anthropology and edge-of-the-seat population study,” said Henry C. Harpending, a distinguished professor and endowed chairman of anthropology at the University of Utah and a member of the National Academy of Sciences who was not involved with the research. “The idea that people were stuck in Beringia for a long time is obvious in retrospect, but it has never been promulgated. But people were in that neighborhood before the last glacial maximum and didn’t get into North America until after it. It’s very plausible that a bunch of them were stuck there for thousands of years.”

As for Beringia, sea levels rose about 10,000 to 11,000 years ago, submerging the land and creating the Bering Strait, which now separates North America from Siberia with more than 50 miles of open, frigid water.

“Our theory predicts much of the archeological evidence is underwater,” said Andrew Kitchen, a Ph.D. candidate in the anthropology department at UF who participated in the research. “That may explain why scientists hadn’t really considered a long-term occupation of Beringia.”

UF researchers believe that their synthesis of a large number of different approaches into a unified theory will create a platform for scientists to further analyze genomic and non-genetic data as they become available.

Except for 1987, when there were no fatalities, the last year a single human death occurred from a shark attack was in 1985, said George Burgess, director of the International Shark Attack File housed at UF’s Florida Museum of Natural History. By comparison, there were four deaths each in 2005 and 2006, and seven in 2004.

“It’s quite spectacular that for the hundreds of millions of people worldwide spending hundreds of millions of hours in the water in activities that are often very provocative to sharks, such as surfing, there is only one incident resulting in a fatality,” he said. “The danger of a shark attack stays in the forefront of our psyches because of it being drilled into our brain for the last 30 years by the popular media, movies, books and television, but in reality the chances of dying from one are infinitesimal.”

Advances in medical treatment, greater attention to beach safety practices and increased public awareness about the danger of shark attacks are all likely reasons the fatality rate so far for the 21st century, at 7.6 percent, has been lower than the 12.3 percent recorded for the 1990s, Burgess said.

The number of shark attacks overall increased from 63 in 2006 to 71 in 2007, continuing a gradual upswing during the past four years, he said.

“One would expect there to be more shark attacks each year than the previous year simply because there are more people entering the water,” he said. “For baby boomers and earlier generations, going to the beach was basically an exercise in working on your suntan where a swim often meant a quick dunking. Today people are engaged in surfing, diving, boogie boarding and other aquatic activities that put them much closer to sharks.”

Occasionally, the number of attacks may drop in a particular year because of changes in meteorological or oceanographic conditions that affect water temperature and salinity, such as the frequency of hurricanes and tropical storms, Burgess said. But scientists don’t put too much stock in these year-to-year fluctuations, preferring to look at long-term trends, he said.

Traditionally, about half of the world’s attacks occur in United States mainland and Hawaiian waters, but the proportion was greater in 2007, Burgess said. Last year’s total of 50 attacks returned to 2000 and 2001 levels of 53 and 50, respectively, after dropping from 30 to 40 for each year between 2003 and 2006, he said.

Elsewhere, there were 12 attacks in Australia, up from seven in 2006 and 10 in 2005, but down slightly from the 13 attacks recorded in 2004. There were two attacks each last year in South Africa and New Caledonia, with single incidents reported in Fiji, Ecuador, Mexico and New Zealand.

There also was an upswing in attacks along the Florida coast, jumping from 23 in 2006 to 32 in 2007. There has been a gradual increase in human-shark skirmishes in the Sunshine State since they dropped from 37 in 2000 to an 11-year-low of 12 in 2004, he said.

Within Florida, Volusia County continued its dubious distinction as the world’s shark bite capital with 17 incidents, its highest yearly total since 2002, Burgess said. Attractive waves off New Smyrna Beach on the central Atlantic coast are popular with surfers, he said.

Additional U.S. attacks were recorded in Hawaii — seven — marking a five-year-high, along with South Carolina, five; California, three; North Carolina, two; and Texas, one.

Fifty-six percent of the 2007 victims were surfers and windsurfers; followed by swimmers and waders, 38 percent; and divers and snorkelers, 6 percent.

Last year’s Sept. 30 fatal attack involved a 23-year-old woman from France who was snorkeling off the Loyalty Islands archipelago in French New Caledonia and became separated from a friend, Burgess said. She was a nurse who had just finished a hospital contract in Noumea and was taking a brief vacation before flying home, he said.

“We advise not getting yourself isolated because there is safety in numbers,” he said. “Sharks, like all predators, tend to go after solitary individuals, the weak and the infirm, and are less likely to attack people or fish in groups.”

Last year had few spectacular attacks or heartwarming rescue stories, Burgess said. “It was mostly minor injuries,” he said. “There weren’t too many made-for-movie moments.”

“It’s kind of quirky that a parasite we love to hate can actually inform us how we traveled around the globe,” said David Reed, an assistant curator of mammals at the Florida Museum of Natural History on the UF campus and one of the study’s authors.

DNA sequencing found the strain of lice to be genetically the same as the form of body lice that spawns several deadly diseases, including typhus, which was blamed for the loss of Napoleon’s grand army and millions of other soldiers, he said.

The discovery of these parasites on 11th-century Peruvian mummies proves they were infesting the native Americans nearly 500 years before Europeans arrived, Reed said. His findings are published this week in an online edition of the Journal of Infectious Diseases.

“This definitely goes against the grain of conventional thought that all diseases were transmitted from the Old World to the New World at the time of Columbus,” he said.

It came as a surprise to Reed and his research team that the type of lice on the mummies was of the same genetic type as those found as far away as the highlands of Papua, New Guinea, instead of the form of head lice that is widespread in the Western Hemisphere, Reed said. This latter version, the bane of many school children, accounts for more than half the cases of lice that appear in the United States, Canada and Central America, he said.

“Given its abundance in the Americas on living humans, we thought for sure that this form of lice was the one that was here all along and had been established in the New World with the first peoples,” he said.

“We hope to be able to understand human migration patterns by investigating their parasites since people have carried these parasites with them as they moved around the globe,” he said. “Called a parascript, it’s a whole other transcript of our evolutionary history that can either add to what we know or in some cases inform us about things we didn’t know.”

Looking at evidence from parasites’ perspectives, for example, may yield valuable clues about when the first Americans arrived on the continent and which route they took, Reed said. Building upon this DNA sequencing work, scientists may be able to link the 1,000-year-old lice found in the Western Hemisphere with those in Siberia or Mongolia, confirming existing theories that America’s earliest residents originated there, he said.

Had these immigrants traveled by land masses, there was a very small window of time, about 13,000 years ago, when the glaciers retreated enough to allow passage through the Bering Strait on the way to South America, Reed said. Another proposed theory is a seafaring route, but this would have required sophisticated oceangoing vessels for which no evidence from the time exists, he said.

Being able to chart these early migration patterns would give insight into how these early immigrants lived, Reed said. “If you’re skirting the edge of glaciers, it’s obviously a very cold time period and humans would have needed certain creature comforts just to stay alive, such as tight clothing to maintain warmth,” he said.

Today, the people who don’t have the opportunity to change their clothes are the ones at risk for epidemic typhus, which along with the lesser-known diseases of relapsing fever and trench fever are carried by body lice, Reed said. These pests lay their eggs in clothing fibers and washing the clothes is all it takes to get rid of them, he said.

“The disease pops up primarily in refugees who have been displaced from their homeland with the clothes on their backs and nothing else,” he said. “They’re living in crowded conditions where hygiene is poor.”

Reed said he hopes the team’s lice research might someday increase human understanding of typhus by pinpointing where the disease originated.

Studying parasites to learn about their hosts’ history has been around for only about 20 years, Reed said. “By looking at things like tapeworms, pinworms, lice or bedbugs that humans have carried around for at least tens of thousands of years, and in some cases millions of years,” he said, “we can learn much more about human evolutionary history.”

Reporting Feb. 7 in the journal Nature, researchers from the University of Florida, the Foundation for Applied Molecular Evolution and the biotechnology company DNA2.0 describe how they reconstructed proteins from ancient bacteria to measure the Earth’s temperature over the ages.

“By studying proteins encoded by these primordial genes, we are able to infer information about the environmental conditions of the early Earth,” said Eric Gaucher, president of scientific research at the Foundation for Applied Molecular Evolution in Gainesville and the study’s lead scientist. “Genes evolve to adapt to the environmental conditions in which an organism lives. Resurrecting these since long-extinct genes gives us the opportunity to analyze and dissect the ancient surroundings that have been recorded in the gene sequence. The genes essentially behave as dynamic fossils.”

The team wanted to measure Earth’s temperature billions of years ago to learn more about life on Earth during the Precambrian period. But instead of taking the traditional route — analyzing rock formations or measuring isotopes in fossils — they opted to do what they knew best: protein reconstruction.

“We’ve analyzed the temperature stability of proteins inside organisms that were around during those times,” said Omjoy Ganesh, a structural biologist in the UF College of Medicine’s department of biochemistry and molecular biology. “The ancient oceans were warmer. For ocean organisms living during that time to survive, the proteins within them had to be stable at high temperatures.”

After scanning multiple databases, the scientists struck gold with a protein called elongation factor, which helps bacteria string together amino acids to form other proteins. Each bacterial species has a slightly different form of the protein: Bacteria that live in warmer environments have resilient elongation factors, which can withstand high temperatures without melting. The opposite is true for bacteria that live in cold environments.

Armed with information about when bacterial species evolved, the scientists rebuilt 31 elongation factors from 16 ancient species. By comparing the heat sensitivity of the reconstructed proteins, they were able to discern how Earth’s temperature changed over the ages.

“Although the concept of ancestral gene resurrection was proposed more than 40 years ago, the development of efficient gene synthesis has only recently enabled the synthesis of ancestral genes,” said Sridhar Govindarajan, co-author of the paper and vice president of informatics at DNA2.0, a California-based company that constructed the genes. “Gene synthesis allows for a direct route from a calculated gene sequence to a protein that can be tested for function in the laboratory.”

Almost all bacteria are related if you go back far enough, the scientists said. Even organisms that like extreme heat are related to organisms that are very sensitive to temperature change. The key is determining when, during Earth’s history, each type of bacteria came into existence.

“Remarkably, our results are nearly identical to geologic studies that estimate the temperature trend for the ancient ocean over the same time period. The convergence of results from biology and geology show that Earth’s environment has continuously been changing since life began, and life has adapted appropriately to survive,” Gaucher said.

At least that’s how University of Florida researchers interpret the results of new research on the mating habits and nervous systems of prairie voles. An article about the research, which examined both the voles’ behavior and their brains, appears in this week’s edition of the Proceedings of the National Academy of Sciences.

Prairie voles, aka Microtus ochrogaster, are common native rodents in the central U.S. and southern Canada. Because they mate for life and are relatively easy to study, the mouse-like creatures have been the subject of much research by scientists probing questions of monogamy and sexual faithfulness among mammals.

Steve Phelps, an assistant professor of zoology and one of the paper’s three authors, said many male voles pick a female partner and settle in a territory — often for life. A minority, however, shirks steady partners and home bases, instead ranging across other males’ turf and mating with other males’ females.

Alexander Ophir, a postdoctoral associate in zoology at UF, is the paper’s lead author and conducted the research, which is funded by the National Science Foundation. Ophir, Phelps and Jerry Wolff, a biologist at St. Cloud State University in Minnesota, set out to find out what makes the male “wanderers” wander — behavior all the more puzzling because faithful males enthusiastically defend their partners, lunging at and biting the interlopers.

In their natural habitat, the voles spend their time amid tall grass, where they are difficult to observe. So the researchers radio-collared 48 lab-raised males and 48 lab-raised females, divided them into groups of 12, then placed the groups in eight enclosures in the voles’ native territory in Tennessee. By tracking the collars, the zoologists were able to map the voles’ movements for several weeks.

Once they had identified wanderers, faithful males and likely couplings, the scientists euthanized the voles so they could examine their brains. Through genetic analysis, they also sought to determine the paternity of young carried by the females.

The work quickly led to some surprises.

The researchers originally theorized that the wanderers would have less vasopressin 1a receptor in regions of their brains necessary for forming long-term relationships. Vasopressin 1a receptor is a protein that responds to the hormone vasopressin. Previous experiments have proven that the hormone is essential for the voles’ monogamous behavior — if they are injected with the hormone, they form monogamous pairs; if it is removed, they go on the prowl.

To the researchers’ surprise, the long-term relationship or “pair-bonding” brain regions in straying males had no shortage of receptors, Ophir found.

Other regions of the voles’ brains, however, proved more telling.

In the paper, Ophir and his colleagues report that the dissections and analysis revealed that the wanderers lacked vasopressin 1a receptors in two regions known to be critical for spatial memory — knowledge needed when navigating the environment in search of food — or fun. Stay-at-home voles, by contrast, had lots of receptors in these dedicated spatial regions.

That led the researchers to infer that wandering males may not remember the territories where they are attacked by defending faithful males. So rather than avoiding these risky sites, the males keep returning, possibly enduring repeated attacks but sometimes successfully mating with females. “What we think is that animals that lack this receptor have a hard time remembering where they encountered aggressive males,” Phelps said. “That keeps them coming back, which increases their contact with the females.”

Phelps added that from an evolutionary perspective, the faithful and wandering male strategies likely arose and persisted because both are successful strategies for procreation.

Interestingly, many of the neural and hormonal mechanisms of prairie vole pair-bonding seem to be at play in people experiencing true love. As for whether the research offers any lessons for human behavior, Phelps said it adds to evidence that love and faithfulness are not necessarily dictated by the same cerebral mechanisms.

“In this case, one brain region provides the basis for pair-bonding, while another provides the opportunity for straying,” he said. “In voles at least, what happens in Vegas stays there. That seems to be especially true when they can’t remember much of the trip.

However, ripping out a few mangroves and replacing them with shrimp farms, an important local industry, doesn’t necessarily have to reduce the plants’ power to blunt tsunamis. And in that observation lies a fresh, quantitative approach to how policy makers can protect the environment and allow growth and development that improves local residents’ lives.

So says a University of Florida zoologist and co-author of a paper on the topic set to appear this week in the journal Science.

Brian Silliman, a UF assistant professor of zoology, said governments and managers worldwide are leaning toward a system known as “ecosystem-based management” to achieve environmental protection goals. Contrasting traditional techniques that focus on single species, ecosystem-based management seeks to conserve not only species but also habitats and the services they provide to humans by conserving entire ecosystems.

Under ecosystem-based management, policy makers in Thailand would not only take into account its mangroves, but also the needs of shrimp farmers, threats from ocean pollution, potential damage from storms, and other factors, Silliman said.

Shrimp farming in Thailand has led to destruction of thousands of acres of mangroves and is a major environmental issue in Asia. In many areas, mangroves no longer exist, leaving shoreline towns and cities unprotected from tsunamis. To increase mangroves’ protective services, governments must restore or conserve them.

For Silliman and his colleagues, the question was, can some mangroves be converted to shrimp farms without losing too much storm buffering?

Silliman said that managers might make a common assumption: The amount of benefits from a natural amenity — whether sea grass, forests or mangroves — are linked directly to its
size. So, more mangroves would mean proportionally more storm surge protection, more habitat for juvenile fish and more pollution-filtering capacity.

That assumption inevitably leads to either-or conclusions about environmental protection and development, Silliman said. If more mangroves always means more environmental benefits, then none should be destroyed.

The main point of the Science paper is that assumption and its inevitable conclusion are not always right and should be questioned.

Ecologists have long understood that species reach thresholds at which their environmental benefits to humans are greatest, and saturation points at which those benefits trail off, Silliman said. In other words, the relationship between the amount of services provided by an ecosystem and the area of that ecosystem is not a straight line.

When the authors reviewed studies of the mangroves and how they buffer tsunamis, it quickly became clear that the mangroves don’t offer much protection until they cover a certain critical area, Silliman said. And their protection doesn’t get much better after this area reaches a certain, “saturation” size compared to the size of the vulnerable coast they shelter.

Merging this ecological knowledge and economic valuation theory to create a technique useful in many other scenarios, the researchers assigned dollar values to the mangroves’ protective powers, and then compared those values to the dollars earned from shrimp farming. Their conclusion: Small losses of between 10 and 20 percent of mangroves, where massive expanses of mangroves already exist, are outweighed by gains by shrimp farmers.

In other words, as long as farmers don’t destroy too many of the plants, they can uproot some mangroves, build shrimp ponds and make money – and the remaining mangroves will still protect the shoreline from tsunami storm surges.

“It makes intuitive sense when you say, ‘both sides can benefit,’ but the important quantitative question is, ‘How much land can mangroves give up and not lose that most important service of protection against tsunamis,’” Silliman said. “We provide a technique to answer that question based on combining some basic principles of ecology and economics.”

That said, Silliman noted that the argument assumes there are plenty of mangroves. If most have already been destroyed as is the case in most areas, then restoration, not shrimp farming, is essential, he said. The research was funded by the National Center of Ecological Analysis and Synthesis, and the Packard Foundation, which encourages interdisciplinary research. The authors relied on published studies as part the center’s goal of tying together seemingly unrelated research to find new approaches to solving problems.

Now researchers are reporting that in Africa, this plant-insect teamwork depends on the very antagonist it is intended to ward off: Africa’s big browsing mammals.

In a paper set to appear this week on the cover of the journal Science, the researchers report that elephants, giraffes and other large plant-eaters spur Acacias to “hire” and support ants as bodyguards – and without the mammals, the trees slash their investment in ants, opening both to other attackers. Because many of the mammals are threatened by human activities, the paper’s conclusions serve as a cautionary tale of how people can influence the ecosystem as their impacts cascade down unexpected paths.

“Throughout sub-Saharan Africa these large mammals are threatened by human population growth, habitat fragmentation, over-hunting, and other degradation, so we have to wonder how their loss will affect these ecosystems,” said Todd Palmer, the paper’s lead author and an assistant professor of zoology at the University of Florida. “The last thing you would think is that individual trees would start to suffer as well, and yet that’s exactly what we see.”

Scientists have observed mutualism, or cooperative interactions between different species, throughout the natural world. The phenomenon is also well-known among plants and insects, with some of the earliest observations surrounding ants and plants in Central America.

What sets the Science paper apart is that it shows how easily these relationships, which likely have evolved over many millennia, can fall apart once a critical cog is removed.

Acacias are mostly shrubby trees common across the tropics and sub-Saharan African savannah. They have swollen thorns that serve as nests for three species of biting ants. Healthy trees have hundreds of the thorns, often containing more than 100,000 ants per tree.

Both the ants and the trees benefit from their close cohabitation. The ants get the thorny shelters, as well as nectar they collect from the bases of Acacia leaves. Because the ants swarm in defense against anything that molests the trees, the trees get protection from their chief ostensible nemeses, browsing animals.

That’s when the mutualism is working well. But the research got its start when Palmer noticed that certain Acacias at his research site in central Kenya, which had been fenced off from wild herbivores, looked sickly compared with their unfenced counterparts. That was the opposite of what might be expected, because the browsers feed voraciously on the trees.

Palmer noticed that the sickly trees appeared to have fewer thorn nests, so he began measuring that and other differences on the trees in six experimentally fenced plots and six open plots. The former had been surrounded by an 8,000-volt electric fence for 10 years.

The observations confirmed the fenced trees had fewer swollen thorns. The research also revealed that the fenced trees had fewer active “nectaries” at the base of leaves where the ants sip the trees’ nectar. That indicated the trees were producing less nectar.

Moreover, when Palmer and other researchers jostled the fenced trees, the ants were far less defensive than their counterparts on the unfenced trees. There, the slightest disturbance spurs hundreds of ants to pour out of the thorns.

Without mammals around to eat the trees, sheltering fewer, less aggressive ants would not present a cost to the trees. To the contrary, the trees would seem to be better off, because they would not need to use their resources to support the ants.

But the research revealed that the fewer colonies of weakened ants become less able to defend their territory from another species of ant that, unlike the others, does not have a mutually beneficial relationship with Acacias. Instead, this fourth ant species feeds away from the tree and does not protect it from attackers – in fact, it actually encourages a destructive, wood-boring beetle whose cavities then serve as this ant’s home.

The result appears to be that the trees untouched by browsing mammals are infested with more of the beetles, which is part of the reason that they fare poorly.

Another problem for the fenced trees may be that their ants appeared to gather nectar-like secretions from more aphid-like insects than those on the unfenced trees. This could also serve to weaken the fenced trees, Palmer said. The fenced trees were twice as likely to die as the unfenced ones, and they grew 65 percent more slowly, the paper reports.

The Sloan Digital Sky Survey III, slated to begin mid-year and end in mid-2014, consists of four independent surveys operated by the survey’s consortium. One will probe the distant universe and seek to learn more about mysterious dark energy, while two of the surveys will map the Milky Way and examine origins of stars. The UF-led survey will seek to find giant planets orbiting nearby stars and uncover more about the conditions in which they form.

“What we’re undertaking here is the largest homogeneous survey of planets ever conducted,” said Jian Ge, a UF professor of astronomy and the project’s principal investigator. “We not only want to find more planets, we also want to try to understand the big picture of how and where they form and evolve over time.”

At the heart of the survey — known as MARVELS, short for Multi-object Apache Point Observatory Radial Velocity Exoplanet Large-area Survey – is a UF-designed and built instrument capable of simultaneously surveying as many as 120 stars for planets.

The plan is to use the instrument, which employs a specially designed interferometer, to scour some 11,000 stars for orbiting giant planets — more than three times the number of stars searched by all other telescopes to date. The instrument detects planet signals through measuring the gravitational pull of the planet on the star.

The search is expected to yield not only at least 150 planets, almost double today’s number, but also provide much better understanding of the conditions needed for planets to be present. That’s important for future planet searches, including searches for Earth-like planets, because it will help astronomers narrow their search among millions of stars for those most likely to yield fast or interesting results.

“Only through a systematic, homogeneous survey like this one can we begin to understand different planet populations and probe planet distributions among different type stars and environments,” Ge said. “Also, this survey will provide many signposts for other astronomers using the really big, really expensive telescopes to discover smaller mass planets, possibly Earth-like planets, and also find more systems like our solar system.”

In order to substantially boost the survey speed and sample over current planet surveys capable of single object observations, the MARVELS survey will simultaneously target 120 relatively faint stars. The faintness of the stars largely limits the survey’s sensitivity to giant planets, although the UF instrument has four times the light particle, or photon, collecting power than current single object planet hunting instruments at other telescopes.

The search is expected to begin in the fall, shortly after the instrument is completed and installed. Like the other surveys, the MARVELS survey will be conducted from the 2.5 meter SDSS telescope at Apache Point Observatory in New Mexico.

The Sloan Digital Sky Survey III is a continuation of two previous SDSS surveys in the past eight years. The new survey is expected to be funded in part with a $7 million grant from the Alfred P. Sloan Foundation, with the survey and its four component surveys representing a total investment of about $50 million.

UF’s MARVELS instrument has about $2.5 million in funding, including part of an $875,000 grant from the W.M. Keck Foundation for an earlier, prototype version called the W.M. Keck Exoplanet Tracker. The UF survey is also being funded by the National Science Foundation, NASA and UF. Once the instrument is up and running, UF is expected to receive an additional roughly $6 million in funding for building another survey instrument, operating the survey, and handling the survey data, Ge said.

Ge said an added benefit of UF’s participation in the project is that it will allow UF astronomers free and timely access to data from all of the surveys. “We have full access to all that data, which is a huge scientific resource,” he said.

Stan Dermott, chairman of the UF astronomy department, noted that UF is also a partner with Spain in the world’s largest telescope, the Gran Telescopio Canarias, expected to begin scientific observations this year.

“Over the next 10 years,” he said, “the combination of the SDSS telescope and the GTC telescope may offer UF a unique tool to investigate both giant and Earth-like planets.”

The origins of when flowers managed to harness insects’ pollinating power has long been murky. But the new study, published online this week on the Proceedings of the National Academy of Sciences Web site and appearing in its Dec. 24 print edition, is the first to pinpoint a 96-million-year-old timeframe for a turning point in the evolution of basal angiosperm groups, or early flowering plants, by demonstrating they are predominantly insect-pollinated.

“Our study of clumping pollen shows that insect pollinators most likely have always played a large role in the evolution of flowering plants,” said David Dilcher, a graduate research professor of paleobotany at the Florida Museum of Natural History. “It was true 96 million years ago and we are seeing it today with the potential threat to our agricultural crops because of the collapse of the honeybee colonies. The insect pollinators provide for more efficient and effective pollination of flowering plants.”

The study provides strong evidence for the widely accepted hypothesis that insects drove the massive adaptive radiation of early flowering plants when they rapidly diversified and expanded to exploit new terrestrial niches. Land plants first appear in the fossil record about 425 million years ago, but flowering plants didn’t appear until about 125 million years ago in the Early Cretaceous period.

The study also is the first to describe the biological structure of pollen clumping in the early Late Cretaceous, which holds clues about the types of pollinators with which they were coevolving, said lead author Shusheng Hu, who started the study while at the Florida Museum but is currently at Indiana University Southeast. Hu said previous scientists found examples of early clumped pollen from a slightly earlier time period but these were interpreted as immature parts of anther from a flower, or dismissed as insect packaging activity or fecal pellets.

“We really had to jump out of the box and think in a new way on these widespread pollen clumps,” said Hu, who completed the research in 2006 as part of his UF doctoral work.

Today, flowers specialized for insect pollination disperse clumps of five to 100 pollen grains. Clumped grains are comparatively larger and have more surface relief than wind- or water-dispersed pollen, which tend to be single, smaller and smoother.

“These clumps represent an amazing new strategy in the evolution of flowering plants,” Dilcher said. “For me, the excitement here lies in the early times of these fossil flowers, when angiosperms were making these huge evolutionary steps. What we found with the fossil pollen clumps folds nicely into what has been suggested by molecular biologists that those plants that are basal in angiosperm evolutionary relationships seem to have been dominated by insect pollination.”

The nine species of fossil pollen clumps, combined with known structural changes occurring in flowering plants at this time, led the researchers to suggest that insect pollination was well established by the early Late Cretaceous — only a few million years before the explosion in diversity and distribution of flowering plant families. Known structural changes include early prototypes of stamen and anther, plant organs which lift pollen up and away from the plant, positioning the plants’ genetic material to be passed off to visiting insects.

The researchers sampled pollen from three sites in Minnesota’s Dakota Formation, which represents a time period when a shallow seaway covered North America’s interior.

Co-author David Jarzen, a Florida Museum pollen scientist, refined existing pollen processing techniques for extracting intact fossil pollen from the calcareous Minnesota limestone and silicate mudstone rock matrix. Co-author David Taylor, a botanist from Indiana University Southeast contributed a statistical analysis of pollination methods among living and early plants.

A Smithsonian Institution paleobiologist, Conrad Labandeira, who specializes in insect-plant associations, and who is unassociated with the study, said that the authors’ ability to demonstrate pollen clumping in basal angiosperms adds one more piece to the puzzle of several pollination types established in the mid-Cretaceous.

“These data are very comparable with parallel data such as flower structure, pollen structure, and insect mouthpart morphology, that now documents a wide variety of pollination types that occurred before the Cenomanian,” Labandeira said.

But what if aliens were hunting life outside their own planet? Armed with telescopes only a bit bigger and more powerful than our own, could they peer through the vastness of space and lock in onto Earth as a likely home to life?

That’s the question at the heart of paper co-authored by a University of Florida astronomer that appeared this week in the online edition of Astrophysical Journal. The answer, the authors say, is a qualified “yes.” With a space telescope larger than the Hubble Space Telescope pointed directly at our sun, they say, “hypothetical observers” could measure Earth’s 24-hour rotation period, leading to observations of oceans and the chance of life.

“They would only be able to see Earth as a single pixel, rather than resolving it to take a picture,” said Eric Ford, a UF assistant professor of astronomy and one of five authors of the paper. “But that could be enough for them to identify our planet as one that likely contains clouds and oceans of liquid water.”

This research may sound whimsical, but it has a serious goal: to provide a road map for Earth-bound astronomers trying to study Earth-like planets — a task expected to become possible in coming decades as more powerful telescopes come on line, said Enric Palle, the lead author of the paper and an astronomer with the Instituto de Astrofisica de Canarias.

For humans or curious aliens, observing planets is challenging for a number of reasons – habitable planets all the more so. The planet can’t be too close or too far away from its star, or its surface would scald or freeze. And, it must have a protective atmosphere like Earth’s.

Most planets found so far are much larger than Earth, which means they are likely hot gas planets similar to Jupiter, a profoundly uninhabitable place with no solid surface and atmosphere composed largely of hydrogen and helium.

But astronomers are beginning to plan how future space telescopes could directly detect planets much closer to Earth’s size and proximity to the sun. One challenge: To figure out how to use a planet’s light to recognize if its surface and atmosphere are Earth-like.

For Ford and his colleagues, the answer lies in probing how the Earth would appear to outside or alien observers.

Astronomers have long recognized that even a large telescope would need to observe Earth for several weeks to collect enough light to identify chemicals in the planet’s atmosphere. During these observations, the brightness of the Earth would change, primarily because of clouds rotating into and out of view. If astronomers could measure Earth’s rotation period, then they would know when a given part of the planet was in view. The hitch was that astronomers were unsure whether Earth’s seemingly chaotically changing cloud patterns would make it impossible for alien observers to determine this rotation rate.

Based on data retrieved from satellite observations of Earth, Ford and his colleagues created a computer model for the brightness of the Earth, revealing that on the global scale Earth’s cloud cover is remarkably consistent — with rain forests usually turning up cloudy, arid regions clear, and so on. As a result, extraterrestrial astronomers who watched Earth for a period of several months would notice repeating patterns – a bit like watching the spots on a spinning ball come into view and then disappear. From those repeating patterns, they could then deduce Earth’s 24-hour rotation period, Ford said.

That done, the “E.T.” astronomers could infer that anomalies in the pattern were caused by changing weather patterns, most prominently, clouds, he said. Although some uninhabitable planets are extremely cloudy, the repeated presence and absence of clouds indicates active weather. On Earth, this variability results in water turning from gas to a vapor and back again, so finding similar variability on another planet would be a reasonable indication of liquid water.

“Venus is always covered in clouds. The brightness never changes,” Ford said. “Mars has virtually no clouds. Earth, on the other hand, has a lot of variation.”

Not only that, but observers could likely also infer the presence of continents and oceans from Earth’s changing light pattern.

The research will be useful to astronomers designing the next generation of space telescopes because it provides an outline of the capabilities required for studying the surfaces of Earth-like planets, Ford said. He said it appears that zeroing in on Earth-like planets orbiting the nearest stars would require a telescope at least twice the size of the Hubble Space Telescope. Ford said he hopes that his research will help to motivate an ever larger space telescope that could search for Earth-like planets around many stars.

The other authors of the paper are P. Montañés-Rodríguez and M. Vazquez, both of the Instituto de Astrofisca de Canarias in Spain, and Sara Seager, of the Massachusetts Institute of Technology. The IAC and UF are partners in the construction of the Gran Telescopio Canarias, a 10-meter telescope in the Canary Islands, which will start operations in 2008.

The research was funded in part by a Ramon y Cajal fellowship for Palle, by a Hubble fellowship and UF for Ford, and by a NASA grant for Seager.

MIT release | IAC release in Spanish | IAC release in English