WASHINGTON, Feb. 12 (UPI) -- Every year, dirty air sends some 5.5 million people to an early grave.
That's according to researchers at the University of British Columbia, who on Friday presented new data on air pollution at the annual meeting of the American Association for the Advancement of Science.
"Air pollution is the fourth-highest risk factor for death, globally, and by far the leading environmental risk factor for disease," Michael Brauer, a professor at UBC's School of Population and Public Health, said in a press release. "Reducing air pollution is an incredibly efficient way to improve the health of a population."
The main culprit is particulate matter -- aerosols, smoke, soot, dust and other toxins and fumes suspended in air.
Though industrial fumes and trash fire smoke can fatally suffocate, most of the 5.5 million air pollution-related deaths tallied in the latest research are the result of health complications -- mostly heart disease. Exposure to particulates has been linked to a range of cardiovascular problems, as well as pulmonary diseases, respiratory infections and cancer.
Though air pollution remains a problem in Europe and the United States -- especially for minority communities -- a majority of the 5.5 million deaths are happening in the developing world and Asia.
More than 55 percent of annual air pollution deaths occur in India and China, two countries with expanding economies and serious air quality control problems.
"Our study highlights the urgent need for even more aggressive strategies to reduce emissions from coal and from other sectors," said Qiao Ma, a PhD student in the School of Environment at Tsinghua University in Beijing.
Ma's research suggests pollution from coal alone was responsible for the deaths of 366,000 people in China in 2013.
The new research is meant to inspire action and includes analysis aimed at helping Asia's maturing economies curb air pollution and save lives.
"India needs a three-pronged mitigation approach to address industrial coal burning, open burning for agriculture and household air pollution sources," explained Chandra Venkataraman, professor of Chemical Engineering at the Indian Institute of Technology Bombay, in Mumbai.
The latest study suggests air pollution is even deadlier than previous thought.
A 2015 study put the total at only 3.3 million deaths, but the new numbers suggest those predictions underestimated the human health consequences of air pollution in India, where coal factories and open pit trash fires continue to cost hundreds of thousands of lives.
Those that live in China and India likely won't be surprised by the news. Air pollution in the two nations, especially in big cities, is regularly visible from space and significant enough to consistently block out the sun.
NEWARK, N.J., Feb. 12 (UPI) -- A new comprehensive study of ancient ant fossils suggests the triumphant insect has been socializing and sparring with enemies for at least 100 million years.
The study, published in the journal Current Biology, is based on two main amber fossils -- one which trapped two fighting ants and another that captured 21 ants working in unison.
Scientists say the first is proof that ants have been warring since at least the Cretaceous period, 99 million years ago.
"That's a trait of ants," Phillip Barden, a fossil expert and research scientists at Rutgers University, said in a press release. "Many ant species do that all the time. They're always warring with either other individuals of the same species from different colonies or with different species."
Both intra- and inter-species competition for resources is common in the insect world -- as it is in the animal world. But many scientists say the greatest evolutionary asset of the ant is its tendency toward socialization and cooperation.
An ancient piece of amber trapping a dense group of worker ants is proof their teamwork began early.
"We have one piece of amber with as many as 21 worker ants trapped, and that's significant because at this time period, ants are very rare to find in fossils," Barden said. "They make up less than 1 percent of all insects in amber," he said. "So to find 20 in one piece is highly suggestive of social behavior."
There are at least 13,000 ant species living today, maybe more. Scientists believe some of them are directly related to the species of the Cretaceous period. But though they're certainly an evolutionary success story, some ancient traits haven't survived.
"They actually had these mammoth, tusk-like jaws that we think were used to impale prey," Barden said. "There's nothing like that alive today, especially not in the ant world."
The ants trapped in the newly analyzed amber wouldn't be recognized by their peers today, but no one knows exactly why they disappeared.
"It seems like they probably went extinct sometime in the 10 million years or so before or after dinosaurs went out," he said. "It could have been climate. We also think it's possible that the modern lineages actually out-competed these early ants."