05 Sci-Tech

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TL;DR: Scientists have long been fascinated by the vibrant colors and intricate structures found in the feathers of birds like the Indian Peafowl (commonly known as the peacock). A new study has shed light on a surprising property of these iconic tail feathers: their ability to act as tiny laser resonators when infused with a common fluorescent dye.

The research, conducted by researchers from several US universities and published in Nature, set out to explore the behavior of peacock feather barbules – microscopic structures that help create the bird’s famous shimmering eyespots – when treated with the laser dye rhodamine 6G. The aim was to determine if light emitted from these dyed feathers would reveal insights about the underlying biological structure, and whether the colorful photonic crystals in the feathers themselves might serve as feedback mechanisms to produce laser light.

To conduct the experiment, scientists obtained natural peacock feathers, carefully cut them to isolate the eyespot area, and repeatedly wetted and dried specific regions with a solution containing rhodamine 6G. This dye is well-known for its bright fluorescence when exposed to green laser light. Using pulses from a green laser, the team illuminated the prepared feathers and collected the emitted light through a specialized spectrometer system.

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WASHINGTON (AP) — Scientists say they have at last solved the mystery of what killed more than 5 billion sea stars off the Pacific coast of North America in a decade-long epidemic.

Sea stars – often known as starfish – typically have five arms and some species sport up to 24 arms. They range in color from solid orange to tapestries of orange, purple, brown and green.

Starting in 2013, a mysterious sea star wasting disease sparked a mass die-off from Mexico to Alaska. The epidemic has devastated more than 20 species and continues today. Worst hit was a species called the sunflower sea star, which lost around 90% of its population in the outbreak’s first five years.

“It’s really quite gruesome,” said marine disease ecologist Alyssa Gehman at the Hakai Institute in British Columbia, Canada, who helped pinpoint the cause.

Healthy sea stars have “puffy arms sticking straight out,” she said. But the wasting disease causes them to grow lesions and “then their arms actually fall off.”

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A groundbreaking discovery from Duke University School of Medicine reveals a direct connection between the microbiome and the brain, shedding new light on the regulation of behavior and appetite.

In a major scientific development, researchers have identified a new way the brain and gut interact, unveiling what they describe as a “neurobiotic sense.” This previously unknown system allows the brain to receive immediate signals from the microbes that live in the gut.

The study, published in Nature and conducted by neuroscientists Diego Bohórquez, PhD, and M. Maya Kaelberer, PhD, at Duke University School of Medicine, focuses on specialized cells called neuropods. These tiny sensory cells, found in the lining of the colon, are able to recognize a common protein produced by gut bacteria. Once detected, the neuropods quickly relay signals to the brain, helping to reduce food intake.

According to the researchers, this discovery may only scratch the surface. They suggest that the neurobiotic sense could represent a broader mechanism through which the gut monitors microbial activity. This system might affect not only eating behavior but also emotional states—and potentially, how the brain influences the microbial environment in the gut.

“We were curious whether the body could sense microbial patterns in real time and not just as an immune or inflammatory response, but as a neural response that guides behavior in real time,” said Bohórquez, a professor of medicine and neurobiology at Duke University School of Medicine and senior author of the study.