This is an article from Head to Head, a series in which academics from different disciplines chew over current debates. Let us know what else you’d like covered – all questions are welcome..

Sharon George: Plastics are ingrained in our everyday lives. Since 1950, it’s estimated that we have produced billions of tons of plastic, and most of this is not recycled.

Plastics have spread around the world through oceans, rivers and the air to every part of the planet. In rivers and oceans, plastic moves vast distances and is now found right through the water column of the oceans, from the surface to the deepest trenches.

One of the most baffling puzzles of modern astrophysics is the nature of Fast Radio Bursts, which were discovered in 2007. These are seemingly rare, extremely bright flashes of light with radio wavelengths. They last only milliseconds; originate outside our galaxy, the Milky Way; come from regions with enormously strong magnetic fields; and pass through a significant amount of gas or dust before reaching Earth.

Obesity is a disease where people accumulate more and more fat. When they reach a certain point, their fat stops working and they develop disease, such as type 2 diabetes. But not all fat is bad. The fat that accumulates in obesity is called white fat, but a second form of fat (brown fat) could actually be used to treat obesity.

Brown fat has evolved to turn fuel into heat. In small animals, like mice and voles, brown fat makes heat that helps them survive, even in freezing temperatures.

The idea of scientists tinkering with the genes of babies was once the provenance of science fiction, but now it’s apparently entered the realm of reality: On Nov. 26, Chinese scientist He Jiankui reported the historic live births of twin girls whose genes he had edited. The goal may have been noble: to use CRISPR to alter their genes to include a variant protective against transmission of HIV.

What began as an expedition to record the inscriptions of ancient Egyptian quarry workers produced a remarkable discovery about the Great Pyramid at Giza. My colleagues and I in the Anglo-French joint archaeological mission to the ancient quarry site of Hatnub recently revealed the existence of a well-preserved haulage ramp dating to the time of the Great Pyramid, roughly 4,500 years ago.

The midterm elections are widely expected to usher in this century’s “year of the woman” – an explosion of women entering government.

Massachusetts will likely elect its first black woman to Congress, Arizona is poised to send its first woman to the U.S. Senate, and fully 50 percent of Democratic congressional nominees this year are women.