Plastered skulls represent one of the earliest burial practices in the southern Levant.

This skull probably represents the population ancestral to most modern living humans.

So each skull represents about 27,777 corpses.

The skulls represent people searching for knowledge.

But the skull, with its beak, represented a dramatic innovation.

The scientists said it was too early to know whether the skull represented a species on a direct ancestral line to humans.

The skulls underneath the tree also represent past band members.

The distant sea battle is a Baroque touch, representing the painter's earthly victories, whereas the skull represents memento mori.

Furthermore, it is possible that the skulls represent two different taxa, as one skull shares some traits with a newly discovered unnamed metriorhynchine, also from Mexico.

Only after careful analysis did the scientists conclude that the nearly complete skull and partial jaw represented a completely different genus and species.