PREHISTORIC LIFE HOME
HOW THE HUMAN LINEAGE MIGHT HAVE EVOLVED
 
There will always be gaps in the fossil record and, given that few soft tissues are preserved in the fossil record, models for the evolution of many anatomical features must be based on the comparative anatomy and genomics of modern organisms. These pages represent a possible set of transitions for how the human lineage might have evolved. The ages given for the various stages are derived from either the dates of specific fossils or the assumption that more primitive (and as yet undiscovered) ancestors predate a specific fossil. The information on the evolution of soft tissues and the genome is derived from the comparative anatomy and comparative genomics of the modern representatives of various groups.

THE PRECAMBRIAN

(4.6 billion to 545 million years ago)

ORIGINS
EARLY CELLS
THE FIRST ANIMALS
CNIDARIANS
BILATERANS
COELOMATES
HEMICHORDATES

THE PALEOZOIC ERA

(545 to 250 million years ago)

CHORDATES
CRANIATES
VERTEBRATES
JAWED FISH
BONY FISH
SARCOPTERYGIANS
AMPHIBIANS
ANAPSID REPTILES
SYNAPSID REPTILES

THE MESOZOIC ERA

(250 to 65 million years ago)

CYNODONTS
MAMMALS
THERIANS
PLACENTAL MAMMALS

THE CENOZOIC ERA

(65 million years ago to present)

PRIMATES
ANTHROPOID PRIMATES
CATARRHINE PRIMATES
APES
HOMINIDS
Homo