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New research has found that the 6 gram brown thornbill mimics the hawk alarm calls of neighbouring species to scare a nest predator by convincing it that a much bigger and scarier predator - the brown goshawk - is on its way.

Currawongs, which raid the nests and hunt the chicks of thornbills, are also prey to goshawks. Although currawongs normally benefit from listening in on hawk alarm calls of other species, thornbills exploit this and turn it against them.

As well as issuing their own hawk alarm call, thornbills mimic those of the local species to create the impression of an impending hawk attack, which in turn distracts the pied currawong - a predator 40 times larger than the thornbill - providing thornbill nestlings with an opportunity to escape.

Researchers at the U.S. Department of Energy's Princeton Plasma Physics Laboratory (PPPL) have for the first time simulated the formation of structures called "plasmoids" during Coaxial Helicity Injection (CHI), a process that could simplify the design of fusion facilities known as tokamaks. The findings, reported in the journal Physical Review Letters, involve the formation of plasmoids in the hot, charged plasma gas that fuels fusion reactions. These round structures carry current that could eliminate the need for solenoids - large magnetic coils that wind down the center of today's tokamaks - to initiate the plasma and complete the magnetic field that confines the hot gas.

"Understanding this behavior will help us produce plasmas that undergo fusion reactions indefinitely," said Fatima Ebrahimi, a physicist at both Princeton University and PPPL, and the paper's lead author. 

A new study shows how huge influxes of fresh water into the North Atlantic Ocean from icebergs calving off North America during the last ice age had an unexpected effect – they increased the production of methane in the tropical wetlands. Usually increases in methane levels are linked to warming in the Northern Hemisphere, but scientists who are publishing their findings this week in the journal Science have identified rapid increases in methane during particularly cold intervals during the last ice age. These findings are important, researchers say, because they identify a critical piece of evidence for how the Earth responds to changes in climate.

Are males truly essential for reproduction? Female birds, reptiles and sharks living in captivity have sometimes surprised their keepers by giving birth even though, as far as anyone can remember, they have never been housed with a male. Scientists used DNA analysis to solve this mystery some time ago, showing that these offspring were produced by asexual reproduction, a process called parthenogenesis, or “virgin birth.” Although these events have captured tremendous public interest, it was unknown if this ever occurred in wild populations of these animals.

Como propietario usted tiene mucho que hacer. Su trabajo, principalmente, es hacer feliz a su inquilino, aunque eso signifique ver el dinero irse por el desagüe. Pero ¿y si fuera posible mantener el inquilino feliz y ahorrar dinero? Esto se puede lograr “siendo verde”.

Encontrar formas de integrar características ecológicas en sus unidades de alquiler le permitirá ahorrar dinero, ayudar al medio ambiente y atraer a inquilinos de alto nivel. La conservación del...