Sometimes it pays to have big, bad neighbors. Weighing in at about 3 grams, black-chinned hummingbirds (Archilochus alexandri) can do little but stand by and watch Mexican jays 40 times their weight chow down on their eggs. So in the mountains of southeastern Arizona, the hummers have learned to build their nests near goshawk and Cooper’s hawk nests (Accipiter gentilis and Accipiter cooperii). Almost five times bigger than the jays (Amphelocoma wollweberi), the hawks enjoy these birds for lunch. So to avoid hawks swooping down and surprising them, the jays only forage above the hawks’ nests. Thus a cone-shaped safe zone exists below the 20-meter-high hawk nests, extending out about 100 meters, researchers report today in Science Advances. Of 342 hummer nests studied over three years, 80% were near hawk nests—and for good reason.
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The million year old monkey
An international team of scientists have dated a species of fossil monkey found across the Caribbean to just over 1 million years old.
The discovery was made after the researchers recovered a fossil tibia (shin bone) belonging to the species of extinct monkey Antillothrix bernensis from an underwater cave in Altagracia Province, Dominican Republic. The fossil was embedded in a limestone rock that was dated using the Uranium-series technique.
In a paper published this week in the well renowned international journal, the Journal of Human Evolution, the team use three-dimensional geometric morphometrics to confirm that the fossil tibia does indeed belong to Antillothrix bernensis, a primate that we now know existed on Hispaniola relatively unchanged for over a million years. This monkey, roughly the size of a small cat, was tree-dwelling and lived largely on a diet of fruit and leaves.
Fighting explosives pollution with plants
Biologists at the University of York have taken an important step in making it possible to clean millions of hectares of land contaminated by explosives.
Estudio del MIT señala los beneficios de actuar sobre el cambio climático
Desde la década de 1990, los científicos y los políticos han propuesto limitar la temperatura promedio de la superficie terrestre de la Tierra a 2 grados C por encima de los niveles preindustriales, evitando así los efectos más graves del calentamiento global, como las sequías e inundaciones costeras. Pero hasta hace poco, carecían de una evaluación completa de los posibles beneficios sociales y económicos, desde vidas salvadas hasta economías preservadas, que resultaría de políticas de reducción de emisiones de gases de efecto invernadero diseñado para lograr el objetivo de un aumento de sólo 2ºC.
La plaga de plástico en el océano amenaza a las aves marinas
El 60% de las especies de aves marinas ya tienen plástico en sus entrañas, a menudo hasta un 8% de su peso corporal. Y con el plástico del océano aumentando exponencialmente, esa cifra se elevará al 99% en 2050, amenazando la supervivencia de algunas aves. A menos de que actuemos.
Muchos de ustedes ya han visto las fotografías de los cadáveres de albatros llenas de basura de plástico sin digerir. Pero, ¿Qué tan representativo es eso de lo que enfrentan las aves marinas?
Coastal management strategies in the age of climate change
Coastal decision-makers must move away from considering physical and economic forces in isolation to fully recognise and explain changes to coastlines, according to new research from Cardiff University.
The coastlines where we live, work and play have long been altered by people, but now researchers have investigated why developed coastlines change over time in ways that are fundamentally different from their undeveloped, natural counterparts.