The extant phylogenetic bracket (EPB)
By creating a phylogenetic tree of the nearest relatives of dinosaurs, it is clear that crocodiles evolved before dinosaurs Appeared and that birds evolved after the earliest dinosaurs. Dinosaurs are therefore sandwiched evolutionarily between living crocodiles and living birds animatronic dinosaur.
Anatomical features shared fay both living birds and crocodiles should also be present in dinosaurs because they are quite literally ‘bracketed’ by these living creatures. Sometimes this type of approach can help to deduce biological features among extinct groups even when there is no clear physical evidence for such features. However, given how specialized creatures such as dinosaurs can be, when compared to living crocodiles and birds, this approach must be used cautiously.