The Salla beds record isolated South America
Bolivian sediments preserve a fauna that evolved with no contact with any other continent.
- When
- —
- Duration
- 5 million years
- Known to
- ± 1 million years
- Era
- Oligocene, Cenozoic
The Salla Formation and related Deseadan-age deposits document South America's mammals at a moment when the continent had been isolated for 30 million years: native ungulates unrelated to anything elsewhere, marsupial carnivores, early sloths and armadillos, and the first caviomorph rodents and platyrrhine monkeys following their ocean crossings. The teeth are already high-crowned, evidence that open, gritty habitats developed here millions of years before they did in North America.