Evolutionary biologists urged to adapt their research methods

Synthesizing ancestral molecules can give a clearer view of genetic evolution, says Shozo Yokoyama. Photo of olive baboon by Nivet Dilmen, via Wikipedia Commons. By Carol Clark: To truly understand the mechanisms of natural selection, evolutionary biologists need to shift their focus from present-day molecules to synthesized, ancestral ones, says Shozo Yokoyama, a biologist at Emory University. Yokoyama presented evidence for why evolutionary biology needs to make this shift on Friday, February 15, during the American Academy of Arts and Sciences (AAAS) annual meeting in Boston. “This is not just an evolutionary biology problem, it’s a science problem,” says Yokoyama, a leading expert in the natural selection of color vision. “If you want to understand the mechanisms of an adaptive phenotype, the function of a gene and how that function changes, you have to look back in time. That is the secret. Studying ancestral molecules will give us a better understanding of genes that could be applied to medicine and other areas of science.” For years, positive Darwinian selection has been studied almost exclusively using comparative sequence analysis of present-day molecules, Yokoyama notes. This approach has been fueled by increasingly fast and cheap genome sequencing techniques. But the faster, easier route, he says, is not necessarily...

Read More........→May 27, 2013

How do Birds get their Color?

.. A Lilac-breasted Roller shows off Birds have captivated us for time eternal, not only because of their ability to fly, but also because of the color they add to our lives. Ok, let me be clear that I’m not suggesting that ALL birds are colorful. Birds like Plain Chachalacas and Grey Catbirds hardly evoke images of stunning beauty. But a vast number of species DO exhibit dazzling displays of color. And these displays are not always what they might seem. Have you ever wondered why grackles look iridescent blue in good light and black in bad light? Or why the colorful gorgets of male hummingbirds appear and then disappear without warning? This is because color in birds is not a simple thing. But rather it is a complex concoction of some very specific recipes. There are two main ingredients that are essential in the making of color. The first is pigment and the second is keratin. And the ways in which these two fundamental ingredients are added to the color cooking pot are what produces the final colors that we see. Pigments are relatively simple color makers. There are three main pigments that give feathers their colors. The first pigment is called melanin and it produces black or dark brown coloration. Melanin is also very strong and is thus often reserved for the flight feathers. White feathers...

Read More........→September 26, 2014

Indian scientists produce green hydrogen by splitting water molecules

New Delhi, (IANS) A team of Indian scientists from the Centre for Nano and Soft Matter Sciences (CeNS), Bengaluru, an autonomous institute of the Department of Science and Technology (DST), have developed a scalable next-generation device that produces green hydrogen by splitting water molecules.Green hydrogen is one of the cleanest fuels known, capable of decarbonising industries, powering vehicles, and storing renewable energy. Yet, until now, scalable and affordable production methods remained elusive.The CeNS team developed green hydrogen using only solar energy and earth-abundant materials, without relying on fossil fuels or expensive resources.“By selecting smart materials and combining them into a heterostructure, we have created a device that not only boosts performance but can also be produced on a large scale,” said Dr. Ashutosh K. Singh from CeNS, who led the research.“This brings us one step closer to affordable, large-scale solar-to-hydrogen energy systems,” he added.In the research, published in the Journal of Materials Chemistry A, the team designed a state-of-the-art silicon-based photoanode using an innovative n-i-p heterojunction architecture, consisting of stacked n-type TiO2, intrinsic (undoped) Si, and p-type NiO semiconductor layers, which work together to enhance charge separation and transport efficiency.The...

Read More........→June 24, 2025