Carrion crows have counting skills seen only in people

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Carrion crows (Corvus corone) can reliably caw a number of times from one to four on command — a skill that had only been seen in people. Over several months, birds were trained with treats to associate a screen showing the digits, or a related sound, with the right number of calls. The crows were not displaying a ‘true’ counting ability, which requires a symbolic understanding of numbers, say researchers. But they are nevertheless able to produce a deliberate number of vocalizations on cue, which is “a very impressive achievement”, says neuroscientist Giorgio Vallortigara.

Nature | 3 min read

Reference: Science paper

Industrial chemists’ favourite materials have just got an upgrade. Revolutionary materials called metal–organic frameworks have taken chemistry by storm, because of their ability to store astonishing quantities of ‘guest’ molecules. Now scientists have swapped out the expensive metal part of the metal-organic frameworks with salts. Organic frameworks using salts have been made previously, but they were unstable and therefore not particularly useful. But the latest effort created stable frameworks that were relatively inexpensive and easy to synthesize. They may have applications in cleaning up nuclear waste, say the researchers.

Nature | 4 min read

Go in-depth with the Nature News & Views article (8 min read)

Reference: Nature paper

Features & opinion

Two new software tools, Find My Understudied Genes (FMUG) and the Unknome database, help researchers identify interesting genes that have been neglected by science. FMUG helps people to narrow a list — such as possible targets from genome-scale sequencing studies — using various filters, including the gene’s popularity in the published literature. Given a set of genes, the Unknome database identifies orthologs — those with common ancestry — in other species, then counts the number of published findings on each gene and its relatives, weighted by the strength of the evidence behind the finding. “We are in the lucky position to know what we don’t know,” says biologist Thomas Stoeger, a co-author of the study that spawned FMUG.

Nature | 6 min read

A scientist on the brink of inventing time travel must wrestle with the implications of his discovery in the latest short story for Nature’s Futures series.

Nature | 6 min read

In his new book Growth, economist Daniel Susskind delves into the impacts of the global economy’s 200-year growth spurt and how to move forward sustainably. Susskind proposes a ‘weak degrowth’ strategy, which dictates the direction of innovation — towards green technologies, for example — to reduce negative effects and uses participatory democracy to make hard decisions. “There are insightful parts and I support a plea for a moral reckoning,” writes ecological economist and reviewer Rutger Hoekstra. “But the book omits crucial environmental insights and lacks the robustness needed for such a foundational debate around the goals of society.”

Nature | 4 min read

Research in mice has shown that fentanyl addiction is the result of two brain circuits working in tandem, rather than a single neural pathway as had been previously thought. One circuit underlies the positive feelings this powerful drug elicits, while the other was responsible for the intense withdrawal when it is taken away. Opioid addiction leads to tens of thousands of deaths each year, and the team hopes that this work will help in the development of pain treatments that are less addictive.

Nature Podcast | 27 min listen

Go in-depth with the Nature News & Views article (8 min read)

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