MainzToba cooled the planet half a degree, not a catastrophe.
The finding undercuts a genetic theory blaming Toba for a near-extinction human bottleneck.
Annual mud layers from Kenya’s Lake Chala, read like tree rings, show cooling lasted 18 months, geoscientist Jinheum Park’s team found.
The bottleneck’s cause stays unresolved; researchers now want ash records from more sites.
Sources: Ars Technica