This issue’s round-up of science news

By Jens Magnusson, Irina Pader, Iskra Pollak Dorocic

LANGUAGE EVOUTION LINKED TO CLIMATE

If you’ve ever tried to learn Chinese, you might have found it difficult to master the fantastically varied pronunciation of its vowels. In contrast to English or Swedish, the tonal complexity of Chinese is very high. In a new study, researchers found that tonal complexity tends to be higher in languages that evolved in warm, humid climates (like Chinese) than in those where it’s cold and dry. This is because humidity affects the precision of the vocal chords. As a result, speakers in arid spots have come to rely less on tonal variations for transmitting information. (Everett et al., PNAS, 2015)

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IMMUNE SYSTEM NOT ONLY GENETIC

Have you been sick the whole winter and asked yourself why everyone healthy seems to be blessed with better genes? New research suggests that it is our life habits and environmental factors that determine our immune system and not our genes. In this study, 105 healthy twin pairs were vaccinated against the flu and 204 parameters were analyzed in blood samples from before and after the vaccination. Interestingly, most of the parameters were influenced by diet, prior infections and environmental influence instead of the genetic background. (Brodin et al., Cell, 2015)

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WAKING UP NEURONS

As spring arrives, mammals that have spent the winter in hibernation are waking up. This poses a surprising challenge to their brains. Synapses, the connections between neurons, have degenerated during the cold winter, in a process similar to what happens in early stages of Alzheimer’s disease in humans. Unlike humans, hibernating mammals re-establish lost synapses perfectly upon waking up. A new study found that RBM3, a cold-shock protein, is responsible for this synaptogenesis. The results suggest cold-shock as a potentially protective therapy for neurodegenerative diseases. (Peretti et al., Nature, 2015)

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LESS CANCER PROTEIN, LONGER LIFE 

Mice live longer, seem to age slower and are healthier if they express lower levels of the cancer-promoting transcription factor MYC. MYC is required for survival as it promotes cell growth, but high levels are often found in cancer. Recent research shows that low levels of MYC, e.g. mice with only one copy of the Myc gene, lived 15 % longer than those with two copies of the gene, although both mice types developed identically. But mice with low levels of MYC had a faster metabolism and less severe age-related conditions. (Hofmann et al., Nature, 2015)

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HUMAN VS MOUSE BRAIN

The human brain is unique because of its size and the folded structure of its cortex, something that animals with smaller brains lack. Scientists have now found one gene which seems to be involved in these evolutionary changes of our brains, and thus our cognitive powers. The team genetically compared the stem cells of human and mouse brain tissue. The human brain expressed 56 genes which the mouse didn’t, the most active of which is ARHGAP11B. This gene was then inserted into the mouse genome which resulted in doubling of the animal’s cortical stem cells, and even in some cases developing of cortical folds. (Florio et al., Science, 2015)

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YOUNGER SCIENTISTS MORE INNOVATIVE

A new study has shown that the conventional wisdom is true: younger researchers are more creative than old ones. Analysis of 20 million biomedical papers found that junior researchers published on more innovative topics than their senior counterparts. The method could not directly measure creativity, rather the researcher’s eagerness to embrace new ideas, by looking at key words in titles and abstracts of papers. All is not lost for older scientists though, a previous study showed that the age at which scientists make Nobel Prize winning discoveries is in fact going up. (Nature News, February 15, 2015)

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