The Herodotean report of gold-guarding griffins in the far north, possibly the fossil bones of Protoceratops wearing feathers in translation.
Documented
Aristeas's itinerary
The report chain: Aristeas of Proconnesus's lost Arimaspea, preserved through Herodotus, describes Issedones, one-eyed Arimaspi, gold-guarding griffins, and beyond them the Hyperboreans. The griffin enters Greek art at exactly this period, a monster with a return address.
Assessment: Documented: Herodotus 3.116 and 4.13-27, and the 7th-century griffin boom in Greek art.
Stories
The Protoceratops hypothesis
Adrienne Mayor's famous case: Gobi gold prospectors met exposed Protoceratops skeletons, beaked, four-legged, lion-sized, and the griffin is the fossil interpreted by men digging for gold. Paleontology as the mother of monsters.
Assessment: Stories: Mayor's hypothesis is influential and contested; the fossil-beds argument is circumstantial by design.
Interesting claims
The translation chain
The deeper lesson: the griffin is a relay error, fossil to prospector to Issedonian to Aristeas to Herodotus, four translations deep and still traceable. Every ancient wonder-report is a game of telephone with cargo; the gold made it through, the beak made it through, the anatomy did not.
Assessment: Interesting: the telephone structure is the report's own format; what survived the chain is data, what mutated is monster.
Sources and further reading
Herodotus 3.116, 4.13-27, the Aristeas chain
Adrienne Mayor, The First Fossil Hunters (2000)
Peter James and Nick Thorpe's counterarguments, on the fossil hypothesis
Worth asking
How many monsters are fossils with a travel budget?