Did violent volcanoes in Russia, Greenland and Alaska affect the lives of ancient Egyptians? It may sound improbable, but according to a new study, the answer is yes. In a paper published Tuesday in Nature Communications, a team of researchers shows that explosive volcanic eruptions in high northern latitudes of the globe can impact the Nile watershed, causing the flow of one of the worldís mightiest rivers to slow.
This in turn could keep the lower Nile from flooding in the late summer months ó a regular occurrence on which ancient Egyptians relied to irrigate their crops. No Nile flooding meant no irrigation, which meant a bad year in the fields, low food supplies and ultimately, researchers say, civic unrest.
"Itís a bizarre concept that Alaskan volcanoes were screwing up the Nile, but in fact, thatís what happened," said Joseph Manning, a historian at Yale University who worked on the study. He said the idea to compare geological evidence of volcanoes with records kept by the ancient Egyptians occurred to him about two years ago. He was at a dinner with geographer Francis Ludlow, now at Trinity College in Dublin, who had contributed to a seminal study that re-dated volcanic eruptions and looked at how they may have impacted the climate ó and history ó at the time. Around their third glass of wine, Manning asked Ludlow whether he had any data on volcanoes that erupted from 305 to 30 B.C. ó the centuries that the powerful Ptolemaic dynasty ruled Egypt, and Manningís area of expertise.
When Ludlow pulled the data up on his computer, Manning was stunned. He instantly recognized the dates of some of the volcanoes as corresponding with times of upheaval in Ptolemaic Egypt. "It almost looked too good to be true," Manning said. "And thatís when we started to work."
The authors explain that sulfurous gases released during a powerful volcano can form reflective sulfate aerosols in the stratosphere. Because these aerosols reflect solar radiation, they lead to a cooling effect that can last for one to two years. This, in turn, affects what is known as the hydroclimate, including the amount of surface evaporation and rainfall.
"Itís an indirect response, but because of atmospheric circulation and energy budgets, we find that large volcanic eruptions cause droughts, particularly in monsoon areas," Manning said.
Deborah Netburn, Los Angeles Times
Picture this scenario: You and a co-worker are given a task to complete. The co-worker occasionally pretends to do something but leaves you with all of the drudgery. Now imagine that your co-worker weighs several thousand pounds and has a trunk.
Thatís what happened to an Asian elephant in an experiment looking at social intelligence among animals, which researchers are learning is far more complex than previously thought. In addition to deception ó like that lazy elephant ó there are fascinating examples of cooperation.
For instance, some dolphin moms in Australia teach their daughters to don a sea sponge on their snouts, allowing them to search the seafloor for fish without hurting their noses. This was all revealed in Scientific Americanís "Secret Lives of Animals," a special collectorís edition.
Many of the articles highlight just how much humans have in common with other creatures. Thereís the tear-jerker "When Animals Mourn" by Barbara J. King, a professor of anthropology at the College of William & Mary. It includes an anecdote about a giraffe giving birth to an infant with a deformed foot. The mom stays close to the baby, even though that means not foraging with her herd ó and potentially putting her life at risk. When the young giraffe dies after four weeks, the mom is joined by 16 other females, which all help protect the body from predators.
Pet owners may want to flip directly to "The World According to Dogs," a collection of scientific findings about manís best friend. The most useful tidbit: If a dog wonít play with you, youíre probably just doing it wrong. Patting the floor, picking up a dog, smooching it ó those are all ineffective techniques, according to a 2001 study. Instead, try a different strategy, suggests writer Julie Hecht: "The researchers found that giving chase and running away and lunging forward were associated with play 100 percent of the time."
Vicky Hallett, Washington Post