Baleen whales that still had teeth
Janjucetus and Mammalodon are mysticetes with big eyes and shearing teeth — filter feeding has not arrived yet.
- When
- —
- Duration
- 2 million years
- Known to
- ± 1 million years
- Era
- Oligocene, Cenozoic
Janjucetus, from around 25 million years ago in southeastern Australia, belongs on the baleen whale branch but has no baleen at all: it is a metre-and-a-half predator with large forward-set eyes and sharp teeth for seizing prey. Mammalodon, its relative, appears to have been a suction-feeding mud-grubber. They show that the mysticete lineage was defined first by other characters and only later acquired filter feeding, and that the intermediate stages were varied and strange rather than a smooth progression.