Ants become abundant
After 50 million years as a minor group, ants suddenly appear everywhere in the fossil record.
- When
- —
- Duration
- 16 million years
- Known to
- ± 3 million years
- Era
- Eocene, Cenozoic
Ants originate in the Cretaceous but remain rare in amber deposits from that period, typically under one per cent of insect inclusions. In Eocene ambers, including Baltic amber, they are among the most common fossils, in modern proportions and modern subfamilies. The shift tracks the spread of angiosperm forests, which provide the deep leaf litter and the reliable plant-based food — nectar, seeds, and honeydew from sap-sucking insects farmed by ants — that let colonies grow large. Ant biomass today rivals that of all wild birds and mammals combined.