The Late Devonian mass extinction
One of the big five, spread over millions of years — and possibly caused by plants.
- When
- —
- Duration
- 13 million years
- Known to
- ± 3 million years
- Era
- Devonian, Paleozoic
Between the Kellwasser and Hangenberg events some 19% of families and 50% of genera are lost, in a series of pulses rather than one catastrophe. Origination rates collapse as much as extinction rates rise, so it may be as much a failure to produce new species as a killing. A leading hypothesis blames the newly rooted continents: deep roots weathering rock flushed phosphorus into the sea, triggering algal blooms and anoxia. Recent work disputes this, arguing plant expansion oxygenated the oceans instead.