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Scientists have quantified the small genetic differences between monozygotic twins. Researchers analysed the DNA of 381 identical twin pairs (and 2 triplets) and found thousands of mutations that appeared in one twin and not the other. Twins differed on average by 5.2 early developmental mutations, which occurred after the initial formation of the zygote. Some siblings differed by dozens of mutations, and some did not differ at all. “The implication is that we have to be very careful when we are using twins as a model” for teasing apart the influences of nature and nurture, says geneticist Jan Dumanski.
Features & opinion
An adjunct professorial appointment lets you enjoy your retirement without getting in the way of junior faculty members, writes molecular epidemiologist Juergen Reichardt.
Black holes are so odd that, after Einstein predicted tham with his general theory of relativity in 1915, many scientists wondered whether they could really exist. Now the thrilling gravitational-wave detections of black-hole mergers and first images of black holes have given us first-hand knowledge of the Universe’s most bizarre inhabitants. Exciting astronomical techniques allow physicists to directly observe how the real-world objects compare to the brain-boggling theoretical predictions. “Are black holes strictly the same as you would expect with general relativity or are they different?” asks gravitational theorist Clifford Will. “That’s going to be a major thrust of future observations.”
Where I work
For more than a decade, wildlife ecologist Josh Griffiths has been trapping the elusive platypus (Ornithorhynchus anatinus) to survey the status of their population. “So much remains unknown about them — as solitary animals, they are very hard to capture,” says Griffiths. “The males have a venomous spur on each of their hind feet, so I always hold them by the tail.” Griffiths and his colleagues have developed a citizen-science app for people to submit platypus sightings. (Nature | 3 min read)