Top stories: Giant amphibians, ancient gut bacteria, and genes you don’t need
(LEFT TO RIGHT) NASA/JPL/UNIVERSITY OF ARIZONA; JOANA BRUNO; ALEXANDRA OBREGON-TITO AND RAUL TITO

Top stories: Giant amphibians, ancient gut bacteria, and genes you don’t need

Lucky us: If Jupiter and Saturn hadn’t formed where they did—and at the sizes they did—as the disk of dust and gas around our sun coalesced, then our solar system would be a very different and possibly more hostile place, new research suggests.
Thanks to a fossil discovery in Portugal, we know that 230 million years ago, one of Earth’s top predators was a salamanderlike amphibian that was more than 2 meters long, weighed as much as 100 kilograms, and had a broad flat head the size and shape of a toilet seat.
The slowdown in the West African Ebola epidemic is welcome news—but it’s also creating a new problem. With fewer new cases occurring, it is becoming more and more difficult to test vaccines and drugs. As a result, conflicts are looming over who can test Ebola drugs and vaccines in Guinea and Sierra Leone.
Researchers this week unveiled the largest ever set of full genomes from a single population: Iceland. They've found new disease risk genes, insights into human evolution—and a list of more than 1000 genes that people can apparently live without!
Attention paleo dieters: A new study suggests that humans who live in industrialized societies don’t have the guts to stomach a real hunter-gatherer diet. Compared with hunter-gatherers, industrialized peoples’ intestines have fewer kinds of microbes—and are missing at least one major group of ancient bacteria.
Science| DOI: 10.1126/science.aab0387