Constipation is an underestimated and debilitating medical issue related to the opioid epidemic. As a growing concern, researchers look to new tools to help patients with this side effect of opioid use and aging.

In a new study titled 'Mating strategy flexibility in the laboratory: Preferences for long- and short-term mating change in response to evolutionarily relevant variables', the research team captured the relationship preferences of 151 heterosexual male and female volunteers (75 men and 76 women) by asking them to look at pictures of 50 potential partners, and to indicate whether they would prefer a long or short-term relationship with each.

With countless medical advances and efforts to curb smoking, one might expect that life expectancy in the United States would improve. Yet according to recent studies, there's been a reduction in the rate of improvement in American mortality during the last three decades. According to a new study, a rise in obesity is to blame.

An unexpected source of methane in the environment has been inadvertently discovered.

Nitrogen-fixing bacteria are the chief means by which nitrogen gas in the air is changed into a form that plants and animals can use. Roughly 10 percent of these nitrogen-fixing microorganisms contain the genetic code for manufacturing a back-up enzyme, called iron iron-only nitrogenase, to do their job.

Researchers at Scripps Institution of Oceanography at the University of California San Diego were part of an international team that for the first time used hydroacoustics as a method for comparing the abundance of fishes within and outside marine protected areas (MPAs).

They found that the abundance of fishes was four times greater in Mexico's protected Cabo Pulmo National Park than in areas outside the park. Study authors said that hydroacoustics points the way toward a new, more cost-effective method of assessing fish populations.

UPTON, NY - A collaboration led by scientists at the U.S. Department of Energy's (DOE) Brookhaven National Laboratory has observed an unexpected phenomenon in lithium-ion batteries--the most common type of battery used to power cell phones and electric cars. As a model battery generated electric current, the scientists witnessed the concentration of lithium inside individual nanoparticles reverse at a certain point, instead of constantly increasing.

According to the Guinness World Records, the longest any person has held a continuous vocal note is just shy of two minutes. That's quite an achievement.

Compared to the Pacific midshipman fish, however, the endurance of the human vocal cord is no match. Midshipman fish can generate a mating call that emits continuously from their bodies for a full hour.

Oceans are not the only bodies of water that acidify due to man-made climate change; freshwater systems are likewise affected - and this, in turn, could have an impact on the organisms living in them. This is the conclusion drawn by biologists at Ruhr-Universität Bochum following an analysis of long-term data from a number of freswhater reservoirs across Germany and controlled lab experiments with freshwater organisms.

Increased fluctuations in the path of the North Atlantic jet stream since the 1960s coincide with more extreme weather events in Europe such as heat waves, droughts, wildfires and flooding, reports a University of Arizona-led team.

The research is the first reconstruction of historical changes in the North Atlantic jet stream prior to the 20th century. By studying tree rings from trees in the British Isles and the northeastern Mediterranean, the team teased out those regions' late summer weather going back almost 300 years -- to 1725.

With the increasing advantages of DNA sequencing, University of Cincinnati biologists are unraveling many evolutionary mysteries behind the complex world of spider vision.

Looking closely at the mysterious genetic blueprint for how these peepers developed and function is helping researchers see great opportunities for future research. New studies could include gene therapies in humans with visual problems like macular degeneration or retinal cancer.