Rodents raft to South America
African rodents cross the Atlantic on floating vegetation and found the guinea pigs, capybaras and chinchillas.
- When
- —
- Duration
- 6 million years
- Known to
- ± 3 million years
- Era
- Oligocene, Cenozoic
Caviomorph rodents appear abruptly in South America with no local ancestors and clear African affinities. The only plausible route is an ocean crossing on rafts of vegetation torn from African river mouths — a journey of well over a thousand kilometres, though the Atlantic was narrower then and currents ran the right way. From that founding event come capybaras, guinea pigs, chinchillas, agoutis, porcupines and the extinct Josephoartigasia, a rodent the size of a bull.