Make like a tree and die
Large old trees are rapidly dying, in a situation three ecologists liken to the decline of large mammals such as rhinos and tigers. Their research, published Thursday in the journal Science, describes an increase in deaths of trees 100 to 300 years old. Alarmingly, a range of ecosystems found globally, including forests, savannahs and cities, display similar trends, the scientists said in a release from the ARC Centre of Excellence for Environmental Decisions in Australia.
These older trees play a number of key ecological roles, including housing and feeding birds and other wildlife and the decline appears linked to a combination of factors such as land clearing, farming practices and rapid changes in climate.
The ecologists are calling for more research into the causes and extent of tree death, as well as finding areas where large trees are more likely to survive. – Aleysha Haniff
Researchers have found what could be the earliest known dinosaur to walk the Earth lurking in the corridors of London's Natural History Museum. A mysterious fossil specimen that has been in the museum's collection for decades has now been identified as most likely coming from a dinosaur that lived about 245 million years ago – 10 to 15 million years earlier than any previously discovered examples. The creature was about the size of a Labrador dog and has been named Nyasasaurus parringtoni after southern Africa's Lake Nyasa, today called Lake Malawi, and Cambridge University's Rex Parrington, who collected the specimen at a site near the lake in the 1930s.
"It was a case of looking at the material with a fresh pair of eyes," said Paul Barrett from the Natural History Museum, who worked on the study. "This closes a gap in the fossil record and pushes back the existence of dinosaurs."
The London fossil was studied by researchers in the 1950s, but no conclusion was reached and nothing was published, said Dr. Barrett. "It was a mystery what it was ... It just became this mythical animal." – Reuters
Smoking is for the birds
Birds in urban settings may have a specific reason for weaving cigarette butts into their nests, according to a new paper published Wednesday in Biology Letters. Some birds use fresh plants in their nests to repel parasites, an option that may not be readily available for city birds. Researchers from Universidad Autonoma de Tlaxcala in Mexico suggest cigarette butts may serve the same purpose. They conducted two tests. In one, they measured the weight of cellulose acetate, a material found in cigarette butts, in the nests of birds found on campus. They found that more cellulose corresponded with fewer parasitic mites. The team also attached traps to the nests to test the difference between smoked cigarettes – which would contain more nicotine – and unsmoked cigarette filters on attracting parasites. Fewer mites were caught in traps that used a smoked butt, leading researchers to believe that nicotine may repel pests. More testing needs to be done to determine if the birds are intentionally "self-medicating" with the discarded cigarettes, the report says, but the team believes their findings match with the view that urban creatures adapt techniques learned elsewhere to respond to new challenges. – Aleysha Haniff
In case you missed it
Almost 40 years to the day after the Apollo 17 crew snapped the famed "blue marble" image of Earth floating in space on December 7, 1972, NASA has unveiled "black marble" video views of the planet by night. The cloud-free pictures, taken with a high-resolution visible and infrared imager aboard a NASA and National Oceanic and Atmospheric Administration satellite, capture the night lights of Earth in unprecedented detail. The sensor can capture the equivalent of three low-light images simultaneously, giving researchers the opportunity to study Earth's atmosphere, land and oceans at night.
Wondering why parts of Australia that are mostly uninhabited had so many bright spots? NASA said Friday that wildfires were burning through western Australia while data was collected for the project. The final picture was assembled from satellite images taken over nine days in April as well as 13 days in October, meaning temporary phenomena such as fires or oil drilling may be melded into the composite image. – Reuters/Aleysha Haniff