Writing for The Conversation, Professor Max Telford (UCL Biosciences) explores a new link that may explain how animals evolved from single-celled organisms and how this fits into existing theories on evolution. The next time you go wild swimming, whether in a lake, river or sea, you are probably sharing the water with one of your tiniest, yet closest relatives. This near-family member is a microscopic, single-celled organism called a choanoflagellate . Scientists are still puzzled by how