Strange organisms found in China and dating back to 1.56 billion years ago are evidence that multi-celled life was present on Earth much earlier than previously thought, according to findings published in Nature Communications. Researchers say the life forms are eukaryotes and lived in the sea, resembling algae. "It looks like the leap from single cells to simple multi-cellularity is easy -- in relative terms. It was done many times (over the course of evolution) and this really cements the case that it was done early in the history of eukaryotes," said study co-author Andrew Knoll.
Scientists are still studying how giraffes got their long necks. Genetic analysis suggests that the lengthy neck and the circulatory system needed to pump blood to such heights came about together through a few genetic mutations. Why this happened remains up for debate.
Oceans on Jupiter's moon Europa may have the Earth-like chemistry to support life, according to findings published in Geophysical Research Letters. "We're studying an alien ocean using methods developed to understand the movement of energy and nutrients in Earth's own systems. The cycling of oxygen and hydrogen in Europa’s ocean will be a major driver for Europa's ocean chemistry and any life there, just [as] it is on Earth," said NASA scientist Steve Vance, an author of the study.
A synthetic wire that mimics the sturdy characteristics of spider silk has been developed by scientists in the UK and France. Researchers created composite fibers that stretch and compress like a spider web and could have multiple uses. "While the web is simply a high-tech trap from the spider's point of view, its properties have a huge amount to offer the worlds of materials, engineering, and medicine," said Herve Elettro, an author of the study published in the Proceedings of the National Academy of Sciences.
An artificial intelligence system developed by scientists at the Australian National University Research School of Physics and Engineering has re-created a 2001 Nobel Prize-winning physics experiment, producing a Bose-Einstein condensate in the quantum experiment with surprising speed. "I didn't expect the machine could learn to do the experiment itself, from scratch, in under an hour," said Paul Wigley, an author of the study published online in Nature's Scientific Reports.
Researchers reviewed data on almost 9,500 middle-aged adults and found that although the incidence rates of silent heart attacks were higher in men than in women, the associated increased risk of dying when compared to adults without heart attack was greater in women. In general, silent heart attacks, which accounted for 45% of all heart attacks, were linked to a 34% higher all-cause mortality risk and about threefold greater risk of dying from heart disease, according to the study published in Circulation.
Researchers using functional MRI found that recordings of mothers' voices sparked increased activity in auditory response regions of children's midbrain and cortex as well as the amygdala, compared with control voice recordings. Maternal vocalizations also activated regions involved in rewarding stimuli, memory and self information processing, and face recognition. Researchers also found better social communication skills among children who had stronger brain connections in response to maternal vocalizations. The findings, reported in the Proceedings of the National Academy of Sciences, were derived from studies of 24 children, ages 7 to 12.
A UK study in The Journal of Clinical Investigation revealed that a part of a bacterium activates killer T cells to destroy insulin-producing cells, which can result in the development of type 1 diabetes. "This finding sheds new light on how these killer T cells are turned into rogues, leading to the development of type 1 diabetes," said study co-author Dr. David Cole.
Take a look at our website today and learn more about the honor of membership in Sigma Xi.
Subscribe to American Scientist magazine
Are you taking advantage of everything Sigma Xi, The Scientific Research Society has to offer? American Scientist is the premier interdisciplinary magazine for science and research. Act now and receive a one-year subscription for only $30. Subscribe today.