If you’ve ever thought your poo is just a bunch of dead cells, think again. Most of it is alive, teeming with billions of microbes. Here’s what studies in healthy adults reveal makes up our poo.

Water

Our feces is largely (75%) made up of water, although this differs from person to person.

Modern life has many benefits. Transport, comfy furniture, smartphones, TV, the internet, dentistry and advanced medicine would be at the top of most people’s lists. Our bodies also show signs of responding positively to modern life. In almost every part of the world, we are much taller than we used to be. We also live much longer, with life expectancy inching towards 80 in many wealthy countries, while everyone “knows” ancient humans usually died in their twenties. But what I discovered while researching my book, is that things are more complex than that.

Comic books of the 1950s and 1960s made a point of their potential to terrify, with anthologies from Entertaining Comics, such as Haunt of Fear, Vault of Horror, and Tales of the Crypt, boasting covers with straplines such as “Within these pages dwell creatures from the terrifying beyond!”

As the scale and impacts of climate change become increasingly alarming, meat is a popular target for action. Advocates urge the public to eat less meat to save the environment. Some activists have called for taxing meat to reduce consumption of it.

A key claim underlying these arguments holds that globally, meat production generates more greenhouse gases than the entire transportation sector. However, this claim is demonstrably wrong, as I will show. And its persistence has led to false assumptions about the linkage between meat and climate change.

In the early days of industrial capitalism there were no protections for workers, and industrialists took their profits with little heed to anyone else. Following the growth of the labour movement, the establishment of trade unions and the founding of the welfare state in the first half of the 20th century, corporations in decades after World War II embraced a more open, stakeholder capitalism, where profits were shared between employees, managers and shareholders. This led to a flourishing middle class as workers and communities benefited from the success of the corporations of which they were part.

Over the past few days, the mathematics world has been abuzz over the news that Sir Michael Atiyah, the famous Fields Medalist and Abel Prize winner, claims to have solved the Riemann hypothesis.