The cognitive differences between humans and our closest living cousins, the chimpanzees, are staggeringly obvious. Although we share strong superficial physical similarities, we have been able to use our incredible mental abilities to construct civilizations and manipulate our environment to our will, allowing us to take over our planet and walk on the moon while the chimps grub around in a few remaining African forests.
But a new study suggests that human muscle may be just as unique. Scientists from Shanghai’s CAS-MPG Partner Institute for Computational Biology, together with teams from German Max Planck Institutes, investigated the evolution of metabolites — small molecules like sugars, vitamins, amino acids and neurotransmitters that represent key elements of our physiological functions. Their study found that metabolite concentrations evolved rapidly over the course of human evolution in two tissues: in the brain and, more surprisingly, in muscle. An article describing their findings will be published on May 27th in the open-access journal PLOS Biology.
“Our results suggest a special energy management in humans, that allows us to spare energy for our extraordinary cognitive powers at a cost of weak muscle,” summarizes Dr Kasia Bozek. “The world of human metabolomics is just starting to open up its secrets to us,” adds Dr Patrick Giavalisco, who led the metabolome measurement effort at the Max Planck Institute for Molecular Plant Physiology in Golm. “Such human-specific metabolic features we find could be related not only to physical or cognitive performance but also to common human metabolic diseases.”