Environment
PERU
Ancient civilisations of Peru collapsed partially because of the El Nio weather phenomena, states a recent research by the archaeologists of the University of Maine. The archaeologists used mollusk shells to provide evidence for their theory. Mollusks are good indicators of climate because they are sensitive to temperature changes. The researchers found that two species of mollusk, Mesodesma donacium and Choromytilus chorus, which were commonly found in Peru disappeared 2,800 years ago. The researchers attributed this disappearance to an increase in the frequency of El Nio, which also threatened other species and ultimately led to the collapse of the ancient Peruvian civilisations.