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There's no vaccine yet, but Zika researchers are racing to find a good candidate. After testing it in animals, checking for effectiveness in humans might include injecting Zika into healthy people.

The 8-inch insect nearly went extinct when hungry rats overran its island. But Melbourne scientists found a few in 2001 and started a thriving colony. Now the San Diego Zoo is hatching them, too.

Though Zika was discovered in 1947, few scientists since had studied the virus. Now, while some check its genes, others turn to placental cells for clues to any link between Zika and birth defects.

So-called senescent cells no longer divide, but they secrete a mixture of chemicals that can trigger inflammation, which is involved in many age-related disorders. What if the cells were removed?

Clay tablets show that Babylonian astronomers tracked planets using a method that was thought to be invented 1,400 years later. In a way, scientists say, the ancient techniques were "very modern."

When the gloomy octopus of Australia turns dark and towers threateningly over his neighbor, he's likely signaling aggression, scientists now say. Neighbors get the message — they turn pale and flee.

A 2012 New Jersey law was meant to help juries discern factors that make eyewitness testimony strong versus weak. But research suggests a judge's instructions make jurors discount all such testimony.

Something very big, out beyond Neptune, is warping the orbits of small, icy objects circling our sun. Astronomers haven't seen it yet, but say the culprit could be a planet with 10 times Earth's mass.

It's 200 times more powerful than a typical supernova and 570 billion times brighter than our sun. First spotted in June, this stellar monster is wowing astronomers, who wonder what's at its heart.

Scientists are convening to debate whether experiments that make some viruses more contagious in order to advance understanding of potential outbreaks are worth the risk of creating one.

Many analyzing the deal hammered out in Paris say it's way better than no plan at all. But proof, they warn, will be in the execution of efforts to cap global temperature rise at 2 degrees C or less.

Rep. Lamar Smith of Texas is formally investigating a recent study on global warming. Smith calls the timing of the study's publication "suspicious," but many scientists call his tactics "bullying."

It took about 30 teams of scientists worldwide, using supercomputers to churn through mountains of data, to see patterns aligning of what will happen decades and centuries from now.

Leaders from around the world are converging on Paris for the 2015 U.N. Climate Change Conference. The two-week event is designed to allow countries the chance to come to an agreement on stifling climate change.

Below are 10 questions and answers that should better prepare you for the conference and ...

In the past decade, the Gulf of Maine warmed faster than 99.9 percent of the global ocean. The rapid warming explains why recent fishing policies failed to rebuild the cod population, a study finds.

Nearly 200 countries have delegates in Bonn, Germany, this week, trying to figure out how to fight global warming. They're at a difficult point — what the nations have pledged so far isn't enough.

A new study shows people living in hunter-gatherer societies don't get any more sleep than people in the more modern world, despite living without TVs, computers, cell phones and other electronic distractions.

Scientists soared through clouds with a new instrument that takes 3-D pictures of the edge. What they learned about the size and density of droplets surprised them and might lead to better forecasts.

Late-night coffee, tea or cola does more than keep you up, scientists say. The amount of caffeine in a double espresso can delay the internal clock in cells throughout your body by about 40 minutes.