We are the products of evolution, and not just evolution that occurred billions of years ago. As scientists look deeper into our genes (基因), they are finding examples of human evolution in just the past few thousand years. People in Ethiopian highlands have adapted to living at high altitudes. Cattle -raising people in East Africa and northern Europe have gained a mutation (突变) that helps them digest milk as adults.

On Thursday in an article published in Cell, a team of researchers reported a new kind of adaptation - not to air or to food, but to the ocean. A group of sea-dwelling people in Southeast Asia have evolved into better divers. The Bajau, as these people are known, number in the hundreds of thousands in Indonesia, Malaysia and the Philippines. They have traditionally lived on houseboats; in recent times, they’ve also built houses on stilts (支柱) in coastal waters. “They are simply a stranger to the land,” said Redney C. Jubilado, a University of Hawaii researcher who studies the Bajau.

Dr. Jubilado first met the Bajau while growing up on Samal Island in the Philippines. They made a living as divers, spearfishing or harvesting shellfish. “We were so amazed that they could stay underwater much longer than us local islanders,” Dr. Jubilado said. “I could see them actually walking under the sea.”

In2015, Melissa Ilardo, then a graduate student in genetics at the University of Copenhagen, heard about the Bajau. She wondered if centuries of diving could have led to the evolution of physical characteristics that made the task easier for them. “it seemed like the perfect chance for natural selection to act on a population,” said Dr. Ilardo. She also said there were likely a number of other genes that help the Bajau dive.

Healthy eating may offer young children an unexpected gift—it might help them become better readers.

Researchers in Finland found students' reading skills improved more between first grade and third grade if they didn't eat a lot of sugary foods or red meat, and if their diet consisted mainly of vegetables, berries and other fruits, as well as fish, whole grains and unsaturated(不饱和的) fats.

The researchers observed 161 Finnish students. They were between the ages of 6 and 8(first grade to third grade). The researchers reviewed the children's diets and their reading ability using food diaries and standardized reading tests. A healthier diet was associated with better reading skills by third grade, regardless of how well the students could read in first grade, the researchers said.

“Another significant observation is that the associations of diet quality with reading skills were also independent of many other factors, such as socioeconomic status, physical activity, body fat and physical fitness,” said Eero Haapala, a postdoctoral researcher at the University of Eastern Finland and the University of Jyvaskyla.

Does that mean parents of picky eaters should be concerned about their child’s reading abilities? Not necessarily. Although this study found an association between the foods young children ate and their reading skills, it didn't prove cause-and-effect. Still, the researchers said parents, schools, governments and corporations all have an opportunity to enhance academic performance in schools by making healthy foods more available to children.

Exposing living tissue to subfreezing temperatures for long can cause permanent damage. Microscopic ice crystals (结晶体) cut cells and seize moisture (潮气), making donor organs unsuitable for transplantation. Thus, organs can be made cold for only a few hours ahead of a procedure. But a set of lasting new antifreeze compounds (化合物)—similar to those found in particularly hardy (耐寒的) animals—could lengthen organs’ shelf life.

Scientists at the University of Warwick in England were inspired by proteins in some species of Arctic fish, wood frogs and other organisms that prevent blood from freezing, allowing them to flourish in extreme cold. Previous research had shown these natural antifreeze molecules (分子) could preserve rat hearts at -1.3 degrees Celsius for up to 24 hours. But these proteins are expensive to extract (提取) and highly poisonous to some species. “For a long time everyone assumed you had to make synthetic (人造的) alternatives that looked exactly like antifreeze proteins to solve this problem, ”says Matthew Gibson, a chemist at Warwick who co-authored the new research. “But we found that you can design new molecules that function like antifreeze proteins but do not necessarily look like them. ”

Most natural antifreeze molecules have a mixture of regions that either attract or repel water. Scientists do not know exactly how this process prevents ice crystal formation, but Gibson thinks it might throw water molecules into push-pull chaos that prevents them from tuning into ice. To copy this mechanism, he and his colleagues synthesized spiral-shaped molecules that were mostly water-repellent—but had iron atoms at their centers that made them hydrophilic, or water-loving. The resulting compounds were surprisingly effective at stopping ice crystals from forming. Some were also harmless to the roundworm Caenorhabditis elegans, indicating they might be safe for other animals.

“These compounds are really cool because they are not proteins—they are other types of molecules that nonetheless can do at least part of what natural antifreeze proteins do, ”says Clara do Amaral, a biologist at Mount St. Joseph University, who was not involved in the research. Gibson’s antifreeze compounds will still need to be tested in humans, however, and may be only part of a solution. “We don’t have the whole picture yet, ”do Amaral adds. “It’s not just one magical compound that helps freeze-tolerant organisms survive. It’s a whole suite of adaptations.