Fortipesavis

Fortipesavis is known only from a partial left foot preserved in amber, which is a piece of fossilized tree resin.1

Its fourth toe was almost twice as wide as its second toe, a feature not seen in any other bird, living or extinct.12

The foot of Fortipesavis had thick, padded toes with deep grooves between them, which helped it grip tightly onto branches.2

This bird lived in a mangrove forest environment, where it probably perched on thin, swaying branches while hunting for insects.12

The fossil of Fortipesavis was found in a piece of amber that weighs only 2.68 grams and is about the size of a large coin.1

Scientists used micro-CT scanning to study the foot inside the amber without damaging the fossil.1