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Fermented foods such as kimchi contain microbes that are also found in the human microbiome.Credit: Chung Sung-Jun/Getty
Micro-food-ome shows you are what you eat
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.
Reference: Cell paper
The newest bits of our brains age first
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.
Features & opinion
How pregnancy transforms the brain
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.
‘Mobesity’ is hobbling electric cars
‘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.
Futures: Denebian Glamour’s hot or not
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.
Video: How fish hear directionally
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.
Reference: Nature paper
