Today, science estimates some of the human damage done by years of coal burning in China, studies how certain mammals are able to choose the gender of their offspring, gets acquainted with a new atomic clock, and catches a glimpse of an underwater forest.
Pollution in northern China may have reduced life expectancy for many by about 5.5 years
A study published Monday indicates that lifelong exposure to air pollution may have shortened the lives of 500 million Chinese. The effects of air pollution (most of which in China is from coal burning) on lifespan are hard to measure because people tend to move to different places, and therefore experience varying levels of exposure. This, along with other factors like lifestyle and healthcare availability can further confound studies. In a “quasi-experimental empirical approach,” researchers attempted to get a clearer picture of the situation by comparing the health of families who lived on either side of the Huai River.
From 1950-1980, socialist policy provided free coal to families and companies on the north side of the river, but not the south, due to budget constraints. This provided an ideal condition for the study, as most other factors remained the same between the northern and southern groups. The result? Life expectancies were found to be lower (by more than five years) north of the Huai, where pollution concentrations are higher.
Mammals can choose the gender of their offspring, study says
A Stanford study analyzed 90 years of breeding records from the San Diego Zoo, and concluded that, through some unknown mechanism largely controlled by females, mammals are able to choose the sex of their offspring. This builds on a theory first proposed in the early 70s by the famous American sociobiologist Robert Trivers, that certain species would produce sons if the conditions were ideal for sons, and daughters if the conditions were ideal for daughters.
Optical lattice clocks lose just one second every 300 million years
These new clocks are three times as accurate as current atomic clocks. Our current system exposes clouds of caesium atoms to microwaves, but these new clocks use laser beams to excite strontium atoms. Because these laser beams oscillate much faster than microwave radiation, the timing is more precise.
There’s an underwater Cypress forest off the Alabama coast
The story of this forest that's sixty feet underwater? It was buried under ocean sediments, preserved in an oxygen-free environment for more than 50,000 years, and most likely uncovered by hurricane Katrina. Cypress stumps, which cover an areas of at least half a square mile, are so fresh that they smell like sap when cut. There are already fish and wildlife making a home of it, and it will likely be destroyed in just a few years, so have a look: