Ebola may be transmitted by sexual contact

Although researchers have known since 1999 that traces of the Ebola virus could remain in semen for months, two papers published in The New England Journal of Medicine today offer more detail about the frightening possibility that survivors of an infection could rekindle outbreaks. One study focuses on nearly 100 men in Sierra Leone who survived the dreaded viral illness, whereas the second one documents a clear case of sexual transmission of Ebola virus.

In the Sierra Leone study, researchers found Ebola viral RNA in semen samples from almost half the 93 men they tested.  The likelihood of finding viral RNA declined as time from disease onset increased: All nine men who were tested 2 to 3 months after they fell ill had evidence of Ebola RNA in their semen, but the researchers  found it in only 26 of 40 men whose infections had started 4 to 6 months earlier and in 11 of 43 men whose infections had started 7 to 9 months earlier. The result from one Ebola patient tested 10 months after disease onset was indeterminate.

The future of wildfires in a warming world

The history of wildfires over the past 2,000 years in a northern Colorado mountain range indicates that large fires will continue to increase as a result of a warming climate, according to a new study led by a University of Wyoming doctoral student.

“What our research shows is that even modest regional warming trends, like we are currently experiencing, can cause exceptionally large areas in the Rockies to be burned by wildfires,” says John Calder, a Ph.D. candidate in UW’s Program in Ecology and the Department of Geology and Geophysics.

Spring will be springing earlier in the US

Scientists have projected that the onset of spring plant growth will shift by a median of three weeks earlier over the next century, as a result of rising global temperatures.

The results, published today (Wednesday 14th October), in the journal Environmental Research Letters, have long term implications for the growing season of plants and the relationship between plants and the animals that depend upon them.

Re-thinking plant and insect diversity

New research by biologists at the University of York shows that plant and insect diversity is more loosely linked than scientists previously believed. Insects and flowering plants are two of the most diverse groups of organism on the planet. For a long time the richness of these two lineages has been regarded as linked, with plant-feeding insect groups considered unusually species rich compared with their nearest relatives. In a new analysis, based on the most complete tree of insect relationships to date, researchers at the University have shown that there is not a simple relationship between insect diet and diversity.

Winds Carve Away Antarctic Snow

A new study has found that powerful winds are removing massive amounts of snow from parts of Antarctica, potentially boosting estimates of how much the continent might contribute to sea level. Up to now, scientists had thought that most snow scoured from parts of the continent was simply redeposited elsewhere on the surface. However, the new study shows that in certain parts, called scour zones, some 90 percent—an estimated 80 billion tons per year—is instead being vaporized, and removed altogether. 

Nearly 1/3 of world's cacti species facing extinction

Thirty-one percent of cactus species are threatened with extinction, according to the first comprehensive, global assessment of the species group by IUCN and partners, published today in the journal Nature Plants. 

This places cacti among the most threatened taxonomic groups assessed on The IUCN Red List of Threatened Species™ - more threatened than mammals and birds.

Another benefit of beet juice discovered

Ever since human beings first began climbing the world's tallest mountains, they have struggled with a basic problem: altitude sickness, caused by lower air pressures which affect the ability of our bodies to take up oxygen. 

Or, as actor Jason Clarke says in his role as the climbing guide Rob Hall in the recently released movie, Everest, "Human beings simply aren't built to function at the cruising altitude of a 747." 

Swedish sand lizards like climate change

Higher temperatures result in Swedish sand lizards laying their eggs earlier, which leads to better fitness and survival in their offspring, according to research published in the open access journal BMC Evolutionary Biology.

The findings indicate that climate change could have positive effects on this population of high-latitude lizard, but the authors warn that climate change is likely to affect a whole suite of traits, in addition to egg-laying date, which together would have an unknown combined effect on survival and reproductive success.

The relationship between carbon cycles and climate

Making predictions about climate variability often means looking to the past to find trends. Now paleoclimate researchers from the University of Missouri have found clues in exposed bedrock alongside an Alabama highway that could help forecast climate variability. In their study, the researchers verified evidence suggesting carbon dioxide decreased significantly at the end of the Ordovician Period, 450 million years ago, preceding an ice age and eventual mass extinction. These results will help climatologists better predict future environmental changes.

The Ordovician geologic period included a climate characterized by high atmospheric carbon dioxide (CO2) levels, warm average temperatures and flourishing life. Near the end of the period, CO2 levels dropped significantly but precisely when and how fast is poorly known. Kenneth MacLeod, a professor in the Department of Geological Sciences in the MU College of Arts and Science, directed a research team studying the climate changes 450 million years ago to better understand the interactions among the biosphere, the oceans, atmospheric CO2 levels, and temperature.

Ecotourism can put wild animals at risk

Ecotourism, in which travelers visit natural environments with an eye toward funding conservation efforts or boosting local economies, has become increasingly popular in recent years. In many cases it involves close observation of or interaction with wildlife, such as when tourists swim with marine animals. Now, life scientists have analyzed more than 100 research studies on how ecotourism affects wild animals and concluded that such trips can be harmful to the animals, whose behaviors may be altered in ways that put them at risk.