Carl Zimmer once described the aye-aye to me as a “furry Gollum”. This unusual creature is the most ancient of all the lemurs. Its ancestors were among the first to split away from the main lemur line after it arrived on Madagascar. It hunts for grubs at night by tapping on tree trunks with its grossly distended middle finger and listening out with large ears. If it hears the right sounds, it gnaws away at the bark with rodent-like teeth and hauls the grub out with the same narrow finger, wielded like a hook.

Image by Frank Vassen