Most people don't know if they have a hidden extra organ. But they're surprisingly common and often harmless.
Taking the placenta as a case study, researchers are able to piece together how new organs evolve, by repurposing old tissues and using them to do new jobs.
Hormones may not be the only thing that determines how your organs act.
A so-called "organ-on-chip" device could speed up the way drugs are developed. And it's just been named the London Design Museum's design of the year.
“Mini brains” with separate working regions have been grown using stem cells in the lab for the first time. They have similarities…