What the scientists are saying…
One meal a day is good for dogs
Pet owners may feel it is kinder to give their dogs breakfast and supper, but a new study has indicated that feeding dogs just once a day may be better for their health. Researchers at the University of Arizona analysed surveys submitted by more than 24,000 pet owners in the US, and found that dogs that ate just once a day had a lower risk of developing health problems including bone disease and kidney disorders. The study, which has not been peer reviewed, also evaluated the impact of feeding frequency on cognitive function within a smaller set of dogs. Animals that were fed once a day were found to have lower levels of cognitive dysfunction than those that ate more often – equivalent to the difference between an 11-year-old dog and a seven-year-old one. The researchers stressed that the study had not established a causal link: it could be that some dogs are fed more often because they are already unhealthy. However, they noted that “the rationale for twice-daily feeding in dogs is obscure”. “Our study suggests that more frequent feeding may, in fact, be suboptimal for several age-related health outcomes,” the authors said.
Men are more blinded by beauty
It is well-established that people considered beautiful tend to be more successful in job interviews and to make more money than their less-attractive peers. But according to a new study, women are less blinded by beauty than men are. Researchers showed nearly 100 heterosexual men and women pictures of people of the opposite sex, and asked them to decide who they’d trust with their money. The pictures showed a range of faces, from the physically attractive to the threatening, plus a mix of the two. Both men and women were more likely to trust the good-looking people than the ones who looked hostile, but women were less trusting than men of people who were good-looking – but who also looked threatening. “This suggests that a woman’s very attractive face can compensate for her threatening appearance, at least in the eyes of heterosexual men,” said Dr Johanna Brustkern. “Women, on the other hand, are less likely to be blinded by an attractive man.” The study, published in the journal Scientific Reports, concluded that “men and women prioritise attractiveness and threat differentially, with women paying relatively more attention to threat cues”.
“Living robots” can self-replicate
Last year, US scientists announced that they had created the first living robots, by incubating stem cells from a frog called
Xenopus laevis, and gathering them into clusters measuring about 1mm across. Now the team has shown that these
“xenobots” can reproduce, in a way that’s never been observed in plants or animals. The blob-like forms produce “offspring” by sweeping up loose cells that then become new xenobots. This process is called kinematic self-replication, and has previously only been seen in molecules. The researchers had observed that the xenobots – which can propel themselves around using hair-like projections called cilia – sometimes smashed into loose cells, forming new clusters, but these “children” were neither big enough nor strong enough to create “grandchildren”. Using AI, however, the team worked out that if the xenobots formed particular shapes, replication continued. “This work is the realisation of a dream of scientists and science-fiction authors since the 1940s: self-replicating machines,” said Professor Joshua Bongard, one of the project’s leaders. While the research is at an early stage, his hope is that xenobots will one day make themselves useful by, say, collecting microplastics from rivers.
Mammals in decline
Weasels are in such sharp decline in Britain that they should be classed as “vulnerable to extinction”. Populations of Britain’s smallest native carnivore have halved in 50 years, according to a new study. Researchers at the University of Sussex looked at half a million records from surveys that had noted where in the UK mammals were present. In 1971, weasels were found in 50% of 1km squares surveyed, falling to 20% in 2016. Harvest mice were also in sharp decline, while stoats, shrews and voles were merely in decline. Populations of grey squirrels, roe deer and brown rats, and of European badgers, rabbits and moles, were stable.