Top stories: The Ebola outbreak, artificial brains, and tumor-shrinking bacteria

(Left to right): Thomas W. Geisbert; CamiloTorres/iStockphoto/Thinkstock; Wikimedia

Top stories: The Ebola outbreak, artificial brains, and tumor-shrinking bacteria

What does Ebola actually do?

We're hearing a lot about the ongoing Ebola outbreak in West Africa, which has killed 1145 people and sickened more than 2000 so far. But what does the Ebola virus actually do? Much is still unknown, but here are some of the basic things we understand about how Ebola and humans interact.

See all of Science’s coverage of the Ebola outbreak, including the ethics of using experimental drugs, the potential of existing treatments, and the tale of Africa’s first encounter with the virus.

Scientists create artificial brain out of spongy goo

It’s alive! Scientists have created an artificial human brain out of colorful, spongy rings of goo that looks like Play-Doh—except it’s living and may one day even be able to learn. The rings are engineered to mimic the structure and function of the six layers of human cortical brain tissue. Already, researchers are using them to study how neural networks heal and respond to drugs.

Taking antibiotics early in life leaves mice prone to obesity

Taking antibiotics like penicillin early in life might increase your risk of gaining weight. Why? The bacteria that live in your gut go through a growth spurt when you're young. Interrupting their development with antibiotics disturbs the metabolism of young mice and boosts their risk of obesity later on.

Bacteria shrink tumors in humans, dogs

A syringe full of bacteria sounds like the last thing a cancer patient needs. But a new study of dogs with tumors—as well as one human cancer patient—reveals that injecting certain bacteria directly into the growths can shrink or even eliminate them. The results strengthen the case that using bacteria to treat cancer, an approach that performed poorly in some clinical trials, might actually work.

For shark scientists, Shark Week is a blessing and a curse

Everyone loves Shark Week—except  shark scientists. They say that although Shark Week promotes public interest in sharks, the programs often misrepresent what scientists know about the animals and how they study them and may even hurt conservation efforts.

Heads up for the gathering robot swarm

Fish gotta school, birds gotta flock, and robots, it seems, gotta swarm. A team of Harvard and Massachusetts Institute of Technology scientists has built a team of 1024 robots, each a three-legged disk the size of a U.S. quarter. En masse, they form a mechanical multitude an order of magnitude larger than any robot swarm ever built—a possible precursor to future robot work squads choreographed for chores like construction, cleaning, and search-and-rescue.