Meteorite likely chief cause of mass extinction
The meteorite that struck Earth about 66 million years ago was likely the driving factor behind the extinction of the dinosaurs rather than extreme volcanic activity. Researchers examined deep sediments in the North Atlantic to create global temperature data and found that temperatures around the world at the time of the extinction were lower than if volcanoes had been a primary factor.
Researchers have developed a “living concrete” that combines cyanobacteria, sand and a gelatin hydrogel. The material’s photosynthetic microorganisms transform sand and gelatin into a living construction material by absorbing sunlight, nutrients and carbon dioxide to produce calcium carbonate crystals.
Ageotypes: four ways of aging on the molecular level
Researchers have identified four pathways of biological aging after following 43 adults for two years and noting molecular changes over that period. The so-called ageotypes the participants fell into were immune, kidney, liver and metabolic, and these ageotypes may explain why people age differently.
Tiny robots made from frog stem cells could deliver drugs
Scientists used embryonic stem cells from African clawed frogs to develop tiny robotic devices complete with skin and heart muscle and self-healing capabilities, though they cannot reproduce or evolve. The xenobots can not only help scientists learn more about cell biology and regenerative medicine; they could also deliver targeted drugs or scrape plaque from arteries, clean radioactive waste or clear microplastics from the ocean.
Parasite make mice less afraid of predators in general
Mice infected with Toxoplasma gondii parasites lose their fear not only of cats but of any danger, suggesting that the parasite is more generally opportunistic and less specific than previously believed, according to a study in Cell Reports. T. gondii reproduces only in the gut of cats, and infected mice are less fearful of cats, suggesting a specific relationship, but the new research found that infected mice are less anxious and have a stronger tendency to explore.