From compressible cockroaches to plastic pollution... …a selection of scientific theories and discoveries from 2016

Cockroach superpower Cockroaches have an alarming ability to squeeze themselves through the tiniest cracks, and in February, researchers in the US explained how they do it: the bugs have compressible exoskeletons that enable them to squash themselves as flat as two stacked pennies. And even in this state, with their legs splayed outwards, they can move at speed. The team at UC Berkeley is using cockroaches as a model for robots that can get into tight spaces, for use at disaster sites.

Storks favour junk food Storks are abandoning their migratory habits: instead of flying south in winter, they’re hanging around in European cities, so that they can feast on the junk food in landfill sites. Having tracked 48 birds, a team at the University of East Anglia estimates that 14,000 storks are living all year round in Portugal – ten times more than two decades ago – to eat chips and pizzas instead of their natural diets of beetles, grasshoppers and frogs.

Clever fish Could your goldfish pick your face out from a crowd? That was the intriguing possibility raised by a study in June, which found that archerfish – so known because of the way they dislodge insect prey by squirting water at them – are surprisingly good at distinguishing human faces. The fish were trained to squirt jets of water at pictures of faces in exchange for a reward. They quickly learnt which of two faces was the reward face – and could often pick it out when it was presented alongside 43 new faces.

Why birds have better brains That birds are not actually bird-brained is well known. But since their brains are tiny, how do they manage to outsmart many mammals? The answer, according to Czech researchers, is that gram for gram, bird brains contain far more neurons than most mammal brains. For example, although a macaw’s brain is no bigger than a walnut, it has more neurons in its forebrain than a macaque monkey – which has a lemonsized brain.

GM crops “safe” GM foods are safe, a report by a prestigious US body claimed in May. Experts from the National Academies of Sciences, Engineering and Medicine looked at 1,000 studies, listened to 80 speakers, and concluded that there was “no substantial evidence” that GM food harms

human health, but that there was evidence of health benefits. For instance, the so-called “golden rice” crop, rich in vitamin A, has helped prevent blindness in people in some deprived regions. Nor did they find any conclusive evidence that GM crops cause environmental damage. Around 12% of the world’s arable land is planted with GM crops, but only one – cornborer resistant maize, grown in Spain – is legal in the EU.

Greedy Labradors Labradors can’t help being greedy: it’s in their genes. Researchers compared the DNA of 300 Labradors, both lean and obese, and found that the fat dogs were far more likely to carry a mutation that disrupts the production of neuropeptides linked to appetite control. The mutation is believed to affect one fifth of Labradors, and may have developed in a now-extinct ancestor – the St John’s water dog – used by Newfoundland fishermen to retrieve nets from the sea. For those dogs, the tendency to snaffle any food that came their way may have been a distinct advantage. Their greed also makes the dogs easier to train, which may explain why 75% of the assistance dogs included in the study carried the mutation.

A suffering population Around 28 million people in the UK are living with chronic pain, it was reported in June. A team at Imperial College London, analysed 19 studies that contained data on 140,000 people; they concluded that one in seven adults under 25 experience some form of chronic pain, and that nearly two-thirds of the over-75s do. They also found that 14% of adults live with pain that is so bad, it is either moderately or severely disabling.

Plastic pollution

Several studies this year highlighted the harmful effects of micro-pollution; in May, there were calls for plastic microbeads found in cosmetics to be banned, after studies showed that billions were being washed into the sea; in July, fleece clothing came under the spotlight, when it emerged that they shed thousands of polyester fibres each time they are washed; and in October, consumers were urged – once again – not to flush wet wipes down the loo, as these also shed plastic fibres (and they block drains).