#11. Cooperative ‘bots’ don't need a boss

Small, disk-shaped robots that maneuver in formation are just one example of the year's progress in self-organizing machines.

Robots are getting better all the time at working with humans, but this year several teams demonstrated that these machines can also work together, without human supervision. At a time when roboticists are still struggling to improve how well individual robots sense their surroundings and respond to new situations, letting teams of robots execute their own missions may seem premature. But after years of work, researchers have come up with new software and interactive robots capable of cooperating on rudimentary tasks.

In one study, a thousand robots the size of U.S. quarter coins came together like a marching band to form squares, letters, and other 2D formations. The sheer scale required cheap, easy-to-run robots that could efficiently sense where other robots were. In another project, 10 quadcopters radioed their locations to one another and adjusted their paths to avoid collisions and fly in formation, creating a rotating circle.

A third group of robots, inspired by termites, was programmed to build simple structures cooperatively by sensing progress and inferring what the next step needed to be. In yet another experiment, a fleet of robotic boats performed relatively sophisticated group maneuvers, albeit under the command of a central computer that tracked them with a special camera system.

So far, all the collaborative robots rely on relatively crude, local information about their environment and one another, but both they and their sensors are improving rapidly. More, and increasingly impressive, cooperative feats undoubtedly lie ahead. –Elizabeth Pennisi

#10. The birth of birds


Feathers were widespread even among dinosaurs, such as Kulindadromeus, that were not closely related to birds. It took a lot to turn lumbering cousins of Tyrannosaurus rex into agile hummingbirds and graceful swans. This year, evolutionary biologists figured out the mode and tempo of the spectacular evolutionary transition from dinosaurs to birds.

Their analyses top off 2 decades of fossil discoveries, primarily in China, showing that birdlike innovations—particularly feathers—emerged repeatedly among dinosaurs, well before the first birds appeared. Feathers, it seems, were not just for flying, but also for insulation, display, or possibly balance.

In 2014, several groups compiled and analyzed data on many dinosaur and early bird fossils as well as on extant birds, to see when other birdlike traits actually appeared. One study compared 850 morphological traits among 150 species; another measured the thickness of leg bones of 426 species. They discovered that the dinosaurs that ultimately gave rise to birds steadily got smaller and finer boned over time.

Once the bird body plan crystallized, new avian species arose quite rapidly, probably because their small size enabled them to find food and shelter that their larger kin could not exploit. Birds took off, but their dinosaur ancestors had given them a running start. –Elizabeth Pennisi

#8. Youth serum for real?



Old mice thrive when their circulatory systems are linked with those of younger mice, for reasons not yet clear.

This year, in work with profound implications for aging, researchers showed that blood or blood components from a young mouse can rejuvenate an old mouse's muscles and brain. If the results hold up in people—an idea already in testing—factors in young blood could offer the antidote to aging that humanity has sought as far back as Juan Ponce de León's quest for the Fountain of Youth.

Now, in the first clinical trial, 18 middle-aged and elderly Alzheimer's patients are receiving injections of plasma donated by young adults. By this time next year, we may know if young blood can fight one of the most feared diseases of aging. –Jocelyn Kaiser

#7. Chips that mimic the brain


“Neuromorphic” chips inspired by networks of brain cells may excel at data-intensive tasks such as vision.

John von Neumann may have finally met his match. Nearly 70 years ago, the Hungarian-born polymath sketched out the basic design of modern computers, with separate processing, memory, and control units. But this year, computer engineers at IBM and other companies rolled out a promising alternative: the first large-scale “neuromorphic” chips, designed to process information in ways more akin to living brains.

In the future, brainlike processors could transform fields such as machine vision and environmental monitoring, integrating real-time data from sensors from around the globe. –Robert F. Service

#6. Cells that might cure diabetes


Human pancreatic β cells made in the lab produce enough insulin (green) to cure a diabetic mouse 2 weeks after transplant.

β cells respond to rising blood sugar by making insulin, a hormone that allows cells to take up and use glucose. An autoimmune attack that kills β cells leads to type 1 diabetes; replacing them with lab-grown cells might provide a cure.

To use the cells to treat type 1 diabetes, researchers need to develop ways of protecting them from the autoimmune reaction that kills β cells in the first place. Meanwhile, the grown-to-order cells give scientists an unprecedented chance to study diabetes in the lab. Researchers have already started to compare β cells made from skin cells of healthy subjects with those made from patients with diabetes, hoping to pinpoint the key differences. –Gretchen Vogel