This week in science, we covered a lot of exciting stories at IBTimes: a potential diabetes breakthrough that could eliminate daily insulin injections; the career in ichthyology of Japan's emperor; and why lunar eclipses can appear red, pink, orange or black.

But we can't get to everything, so here's a roundup of the other scientific discoveries, inventions and stories that appeared this week:

Was the Maya civilization a successor to the older Olmec culture or an independent group? A University of Arizona professor suggests there's evidence for a third explanation. Archaelogical digs have uncovered the possibility that Maya cities coexisted alongside the Olmec, so perhaps both societies interacted as they developed. [National Geographic]

As noted by Slate, Albert Einstein's theories have withstood a number of challenges over the years -- a comparatively recent one centered on the supposed existence of faster-than-light neutrinos, which later turned out to be erroneous. Now, the father of general relativity has been tested again, and prevailed.

Scientists know that Einstein's theory of gravity doesn't square with what we know about quantum mechanics, so it's probably not the best unified explanation of how gravity works. They put Einstein's ideas about space-time to the test in an examination of a binary-star system 7,000 light-years away from Earth. If Einsten's gravitational theories are correct, the stars should be taking less and less time to circle each other as the years go by -- and that's exactly what happened. [Wall Street Journal]

The Earth's core is hotter than expected by about 1,000 degrees Celsius. [Science Daily]

To comply with the automatic budget cuts necessitated by the sequester, the U.S. Geological Survey will be shutting down more than 100 flood gauges in rivers across the country. Some of the gauges are in states that will be in danger of serious spring flooding in the coming months. [Associated Press]

Sea surface temperatures off the U.S. Northeast coast in the second half of last year were the hottest observed since 1951. []

Georgia Institute of Technology scientists have created a robot model of a baby sea turtle, which gets around on a pair of wooden flippers. The robot's already proven that wrist movements are essential for the real sea turtles to get around on the sand, and could help scientists better understand the movements of ancient animals that first crawled onto land. [Los Angeles Times]

Another Georgia Tech group of researchers broke new ground in robotics this week, coming out with artificial skin that they claim is as sensitive as a person's fingertip. The transparent, flexible material uses thousands of touch-sensitive transistors called taxels, which can sense even a very slight change in pressure. The potential applications are many: robots with a gentler touch, prosthetics that feel like the real thing, and more! [CNET]

Government scientists halted a clinical trial of an experimental HIV vaccine, when researchers found the vaccine appears to have no benefit. During a recent safety review, researchers found that 41 cases of HIV infection cropped up in the group that received the vaccine, as opposed to 30 cases of HIV infection in the group that received the placebo shot. [CBS News]

The U.S. Fish and Wildlife Service is considering taking gray wolves off the list of endangered species. [Los Angeles Times]