Scientists say the crocodiles hunted like leopards by climbing trees and killing prey below.

The egghells belonged to a long-extinct group of crocodiles known as mekosuchines, who lived in inland waters when Australia was part of Antarctica and South America.

Co-author Prof Michael Archer said “drop crocs” were a “bizarre idea” but some were “perhaps hunting like leopards - dropping out of trees on any unsuspecting thing they fancied for dinner”.