April 5, 2018, 12:48 a.m.
Miles de agujeros negros rodean el centro de la galaxia
Descubren varios sistemas binarios de estrellas en los que uno es un agujero negro cerca del núcleo de la Vía Láctea
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Researchers have shown for the first time in an experiment that also non-human animals exchange different kind of favors. Humans commonly trade different commodities, which is considered a core competence of our species. However, this capacity is not exclusively human as Norway rats exchange different commodities, too. They strictly follow the principle "tit for tat" -- even when paying with different currencies, such as grooming or food provisioning.https://www.sciencedaily.com/releases/2018/02/180201173109.htm
