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Unlike mammals, birds have no external ears. The outer ears of mammals play an important function in that they help the animal identify sounds coming from different elevations. But birds are also able to perceive whether the source of a sound is above them, below them, or at the same level. Now a research team from Technische Universität München (TUM) has discovered how birds are able to localize these sounds, namely by utilizing their entire head. Their findings were published recently in the PLOS ONE journal.

Nitrous oxide (N2O) is an important greenhouse gas that doesn’t receive as much notoriety as carbon dioxide or methane, but a new study confirms that atmospheric levels of N2O rose significantly as the Earth came out of the last ice age and addresses the cause.

An international team of scientists analyzed air extracted from bubbles enclosed in ancient polar ice from Taylor Glacier in Antarctica, allowing for the reconstruction of the past atmospheric composition. The analysis documented a 30 percent increase in atmospheric nitrous oxide concentrations from 16,000 years ago to 10,000 years ago. This rise in N2O was caused by changes in environmental conditions in the ocean and on land, scientists say, and contributed to the warming at the end of the ice age and the melting of large ice sheets that then existed.

While unpleasant car exhaust makes us wrinkle our noses, such human-made fumes may pose serious problems to insects searching for nectar. Researchers recently revealed that background odors make finding flowers difficult for pollinators. The study, published in Science, measured how hawk moths (Manduca sexta) pick out the sacred datura flower scent (Datura wrightii) amidst all the other smells that waft through the environment. Datura’s brilliant 15-centimeter trumpets leap from dark, heart-shaped leaves, sending smelly signals into the arid sky of the southwestern deserts where they grow. 

Nearly 269,000 tons of plastic pollution may be floating in the world's oceans, according to a study published December 10, 2014 in the open-access journal PLOS ONE by Marcus Eriksen from Five Gyres Institute and colleagues. Microplastic pollution is found in varying concentrations throughout the oceans, but estimates of the global abundance and weight of floating plastics, both micro and macroplastic, lack sufficient data to support them. To better estimate the total number of plastic particles and their weight floating in the world's oceans, scientists from six countries contributed data from 24 expeditions collected over a six-year period from 2007-2013 across all five sub-tropical gyres, coastal Australia, Bay of Bengal, and the Mediterranean Sea.

Los desarrollos de aerogeneradores no tienen efecto en el valor de las propiedades como casas y granjas cercanas, según una nueva investigación de la Universidad de Guelph.

Publicado en una edición reciente de la revista Canadian Journal of Agricultural Economics, el estudio se cree ser el primero, revisado por científicos, sobre esta cuestión en Canadá.