From: Piotr Gasiorowski
Dear Adriana,Although the Mt Toba eruption was indeed on a scale never witnessed by humans before or since, your estimate of its effects seems greatly exaggerated. Scientists (including geologists) are only human [sigh] and often overdo the dramatic effect if they feel they might get headlines in the popular press. After really great extinctions the earth's ecosphere took much longer than 70 thousand years to recover. True, the falling ashes from the Mt Toba event devastated large areas as far away as India, and it cannot be doubted that global climatic deterioration followed the eruption, but the epic vision of the Urals as an ark carrying human and wildlife survivors looks slightly comic to me. Since Mt Toba didn't even bring about the extinction of orangutans in SE Asia, I can't believe the African and Asiatic populations of anatomically modern humans or their Neanderthal brethren in Eurasia were seriously endangered. The residual Indonesian population of Homo erectus seems to have survived the eruption as well. The Pleistocene fauna of all the continents shows no indication of radical depletion after 71000 BP. If 75% of plants (surely, not plant species?) in the northern hemisphere had been killed, practically all the large herbivores from roedeer to mammoths would have been doomed, and extinction would have propagated up the trophic chain affecting all the large carnivores as well.Piotr----- Original Message -----From: Adriana KamenetskySent: Thursday, August 03, 2000 11:55 AMSubject: originsMount Toba blew 800 cubic kilomenetrs of ash 71,000 years ago. Most of India was buried under it. But the worst was yet to come when it ensued the global volcanic winter for 6 years, which probably killed 75% of plants in the Northern Hemisphere. The constant reflection of the heat from the snow back into the space pushed the Earth into a thousand-year ice age.I believe that humans survived in isolated pockets through out the continents. The Urals are a good possibility - a very old mountain with good fertilizing sediment exposed, with a lot of protection, and wildlife. And the same can be persued through other continents.From time to time, Earth does her cataclismic tricks. 540 millions ago, the buildup of continents at South pole flipped her to the current 23 degree tilt.What if Earth is much much older? Big mistakes were often made at estimating cosmos. What if we lived much longer than is known? Many times humanity was wiped out by disasters almost to the last one of us.(Even the Book tells us so). But we kept on multiplying, developing particular traits, and then we meet at the crossroads, and argue who was there first.Sincerely,Adriana K.