‘Mobesity’ — how bigger vehicles are undermining the benefits of electric cars

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Scientists sequenced microbial DNA from nearly 2,000 foods, including fermented favourites such as Gorgonzola cheese, sauerkraut, kefir and kimchi. About half the microbes the researchers identified were new. Pulque — a sour agave wine drunk in Mexico — was especially rich in this microbial dark matter, as were African palm wine and cheese brine. And a small percentage of people’s gut microbiome matched what was found in food — either because of what they ate or because of some instance in the past when food microbes became established in peoples’ guts.

Nature | 4 min read

Reference: Cell paper

Regions of the human brain that are the last to mature, such as parts of the frontal lobe, are the first to show signs of ageing, a theory known as ‘last in, first out’. New research shows that some of these regions are also the ones that evolved most recently — those linked to decision-making and self-control. The results tend to support the “important hypothesis that our cortical expansion came at the price of age-related decline”, says neuroscientist Rogier Mars.

Nature | 4 min read

Features & opinion

The stereotypical idea of ‘baby brain’ — cognitive issues linked to pregnancy and birth — is pervasive across many societies, but the scientific study of what having a baby does to the brain is still in its infancy. Early evidence seems to show that numerous brain structures shrink during the process — with some bits bouncing back completely and some not. In particular, changes affect a circuit called the default mode network, and correlate with the strength of the mother–infant attachment. Researchers emphasize that shrinkage doesn’t mean a deficit: it’s unlikely that neurons are being lost and most researchers favour the view that shrinkage reflects a refinement of neural functions.

Nature | 9 min read

‘Mobesity’ — the increasing size of vehicles, particularly electric SUVs — is reducing the benefits of the rise of electric cars, argues sustainable-travel researcher Christian Brand. “Larger, heavier and often more powerful electric vehicles not only require more resources to build — thereby increasing their environmental footprint — but also undermine the potential gains from electrification due to their greater energy consumption and associated emissions across the vehicle and fuel lifecycles,” writes Brand. He calls for a nuanced approach that combines policy intervention, technological innovation and shifts in consumer behaviour.

Nature Energy | 4 min read

Discover what’s in and out of fashion for the Galaxy, from the ridiculous to the sublime, in the latest short story for Nature’s Futures series.

Nature | 6 min read

Fish can locate the source of sounds underwater, but exactly how they do this has been a mystery. Now, using a specialist set-up, a team of researchers have demonstrated that some fish can independently detect two components of a sound wave — pressure and particle motion — and combine this information to localize a sound source.

Nature | 4 min video

Reference: Nature paper