Eli5: I understand that 74,000 years ago a supereruption occurred in the Toba volcano that reduced the human population and many other animal species to near extinction. What exactly happened after the eruption that was so deadly for living things?

Question

A super eruption on the Toba volcano produced a bottleneck in the human and in many animal species. How could it be that the eruption of a volcano almost wiped out many animal species?

In: 249

Answer 1

Volcanoes throw a lot of rock, dust, ash and other crap into the atmosphere. These block sunlight from getting to earth’s surface, which reduces global temperatures. The loss of sunlight also adversely affects plant growth (see 1816: the year without a summer)

It’s suspected that if the Yellowstone supervolcano were to erupt then it would make the northern hemisphere almost completely uninhabitable and cut global temperatures by 20°C, triggering a short ice age.