The preference of Heliconius butterflies for certain leaf shapes is innate, but can be reversed through learning. These results support a decades-old theory for explaining the evolution of the exceptional diversity of leaf shapes in passionflowers.
The tropical butterfly Heliconius eratodistinguishes between shapes, and uses them as a cue for choosing the plants on which to feed and lay eggs, shows new research by scientists from the University of Cambridge and the Smithsonian Tropical Research Institute. The butterfly has an innate preference for passionflowers with particular leaf shapes, but can learn to overcome this preference in favor of other shapes, especially those that are the most abundant in the local flora. These preferences can promote the evolution of plant biodiversity.
BUILDING IN RHODE Island isn’t easy. Hurricanes and tropical storms barrel through its quaint coastline towns, interrupting perfect summer weekends. Freezing winters bring blizzards that can shut down the entire state. And every season features corrosive salty winds, biting at the coast as if sent by a Britain still seething at the first American colony to declare independence.
But one company sees the state’s incessant wind as a utility. Deepwater Wind has partnered with General Electric Renewable Energy to build the first offshore wind farm in the United States, off the coast of Block Island. Hooked up to the grid by the end of 2016, the system could supply 90 percent of the tourist destination’s power within the next few years. But it hasn’t been easy. Designing and building spinning fans hundreds of feet tall that stay sutured to the ocean floor in the face of currents and wicked winds has taken almost three years of work.
A new acoustic buoy recently deployed by scientists from the Woods Hole Oceanographic Institution (WHOI) and WCS's (Wildlife Conservation Society) New York Aquarium to listen for some of the world's biggest animals in the New York Bight has detected its first whale species, and it's a really big one.
Fixed in position some 22 miles south of Fire Island and fitted with a digital acoustic monitoring instrument, the hi-tech buoy is now operational and has detected the vocalizations of fin whales, enormous marine mammals second in size only to the blue whale, the largest animal species on earth. The first whale detection was made on Monday, July 4th, only 12 days after the buoy was placed in its current position on June 23rd.
Since that time, the buoy has made several fin whale detections; the most recent vocalizations were detected yesterday (July 27th) and today.
Researchers at the University of Illinois at Chicago have engineered a potentially game-changing solar cell that cheaply and efficiently converts atmospheric carbon dioxide directly into usable hydrocarbon fuel, using only sunlight for energy.
The finding is reported in the July 29 issue ofScience and was funded by the National Science Foundation and the U.S. Department of Energy. A provisional patent application has been filed.
Unlike conventional solar cells, which convert sunlight into electricity that must be stored in heavy batteries, the new device essentially does the work of plants, converting atmospheric carbon dioxide into fuel, solving two crucial problems at once. A solar farm of such "artificial leaves" could remove significant amounts of carbon from the atmosphere and produce energy-dense fuel efficiently.
A new study of over 1 million people finds that doing at least one hour of physical activity per day, such as brisk walking or cycling for pleasure, may eliminate the increased risk of death associated with sitting for 8h a day.
Physical inactivity is linked to an increased risk of heart disease, diabetes and some cancers and is associated with more than 5 million deaths per year and, as the first global economic analysis of physical inactivity shows, costs the world economy over US$67.5 billion per year in health care costs and lost productivity.
Video surveillance is the most effective method for detecting animals flying around solar power towers, according to a study of various techniques by the U.S. Geological Survey and its partners at the Ivanpah Solar Electric Generating System facility in southeastern California.
This study is the first to examine a variety of remote sensing and sampling techniques to determine which technology might be most effective for monitoring how solar power facilities impact flying animals. The information will be used to further study the effects of solar power infrastructure on flying animals -- a subject about which little is known -- and to develop ways to lessen harmful effects.
At Ivanpah, evidence of flying animals impacted by intense heat near the solar towers had been observed. The new study showed that although birds and bats were occasionally seen near the towers at Ivanpah, most observations involved insects.
Montreal homes are the most sustainable in the country, and Edmonton's the least, according to a new University of British Columbia study that compares average household greenhouse gas emissions in major cities across Canada.
Using census data over a 12-year span, researchers ranked cities on how much carbon dioxide the average Canadian family (two to three people) with an annual income of $81,000 in each city produced in a year from the combined use of electricity, gasoline and natural gas.
The average Montreal household produces five tonnes of GHG per family per year, while the average Edmonton household emits 20 tonnes per family per year.
Current levels of atmospheric greenhouse gas concentrations already commit the planet to air temperatures over many land regions being eventually warmed by greater than 1.5°C, according to new research published today (27 July 2016) in the journal Scientific Reports.
The results of the new study have implications for international discussions of what constitutes safe global temperature thresholds, such as 1.5°C or 2°C of warming since pre-industrial times. The expected extra warming over land will influence how we need to design some cities. It could also impact on the responses of trees and plants, and including crops.
The research was carried out by scientists from the UK's Centre for Ecology & Hydrology and the University of Exeter, UK.
The research team found two main reasons behind the result.
Hundreds of millions of birds are killed in collisions with windows each year in the U.S. alone, and although high-rise buildings tend to be the biggest individual culprits, the vast number of suburban homes across the continent means that even a few deaths per house add up fast. A new study in The Condor: Ornithological Applications examines the factors that affect window collision rates at homes and shows that yards that are more attractive to birds are also the sites of more collisions.
Working with Alberta homeowners who collectively contributed more than 34,000 days' worth of collision data, Justine Kummer of the University of Alberta and her colleagues found that the presence of a bird feeder, whether a house was in an urban or rural area, and the height of the vegetation in the yard were the most important predictors of collisions. Of Alberta's 421 bird species, 53 were represented in the data, mostly common urban species.
Although the Amazon Jungle may appear to be perpetually green, a University of Illinois researcher believes there are actually seasonal differences of photosynthesis, with more occurring during the dry season and less during the wet season. Understanding how a rainforest that occupies 2.7 million square miles of South America functions is crucial to the future health of the entire planet.
"With the potential negative effects of climate change, one key question we are trying to answer in the study of tropical ecology is how a tropical forest responds during a long-term drought," says Kaiyu Guan, an environmental scientist at the University of Illinois. "If we don't know their daily performance or their seasonal performance, what confidence can we have to predict the forests' future 20 years, 30 years, or longer?"
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