Breakthroughs, discoveries, and DIY tips sent every weekday. It's a really big deal when fossilized feces survive the ravages of time. These hardened pieces of excrement open up a window into what animals ate thousands of years ago and even what may have made them sick . Humans are not exempt from this, with dried human feces indicating we have always loved cheese and beer and that our microbiome has evolved over thousands of years. DNA recovered from 1,000-year-old dried feces indicates that intestinal infections from pinworm or Shingella may have plagued ancient people living in present day northern Mexico's Rio Zape Valley.

Joaquin Oliver was 17 years old when he was shot in the hallway of his high school. An older teenager, expelled some months previously, had opened fire with a high-powered rifle on Valentine's Day in what became America's deadliest high school shooting. Seven years on, Joaquin says he thinks it's important to talk about what happened on that day in Parkland, Florida, "so that we can create a safer future for everyone". But sadly, what happened to Joaquin that day is that he died. The oddly metallic voice speaking to the ex-CNN journalist Jim Acosta in an interview on Substack this week was actually that of a digital ghost: an AI, trained on the teenager's old social media posts at the request of his parents, who are using it to bolster their campaign for tougher gun controls.