With no written record to describe the rise of the largest pre-Columbian empire, paleoecologists have investigated the climate that existed in the centuries proceeding the Incas' apex. Pollen and seeds found in the sediment in the Cuzco region of the Peruvian Andes reveal a period of climate warming that began around 1100 CE and continued past the Spanish conquest of the Incas in 1533 CE. Alex Chepstow-Lusty of the French Institute for Andean Studies in Lima, Peru, noted such climate change can have a positive effect on civilizations:

"Climate warming does not always have to be a negative issue. Our research shows that it can favor societal development."

In the case of the Incas, four centuries of warm weather melted the glaciers, pumping water into the formerly arid region. Trees were moved up mountains to combat soil erosion, allowing for agriculture in the newly cleared lands. The result was a lengthy period of plenty, with maize and potato crops feeding a growing population and allowing the Incas to turn their attention to assembling a military, building roads and buildings, and creating an infrastructure.

But climate experts warn that future climate change could have disastrous effects:

"Peru is considered the third most threatened country in the world by climate change, with most of its glaciers predicted to disappear by 2050. The country should be focusing on restoring and protecting its ecosystems," Chepstow-Lusty said.

Incan Empire Aided by Global Warming [Discovery News]

The prizes were awarded in a ceremony at Harvard University’s Sanders Theater in ten areas:

• Nutrition: Massimiliano Zampini and Clark Spence for demonstrating that, when the sound of eating a potato chip is modified, the eater believes the chip is fresher and crisper than it really is.
• Peace: The Swiss Federal Ethics Committee on Non-Human Biotechnology and the citizens of Switzerland for adopting the legal principle that plants have dignity.
• Archeology: Astolfo G. Mello Araujo and Jose Carlos Marcelino for demonstrating how the actions of an armadillo may scramble the contents of an archeological dig site.
• Biology: Marie-Christine Cadiergues, Christel Joubert, and Michel Franc for discovering that fleas on a dog jump higher than fleas on a cat.
• Medicine: Dan Ariely for demonstrating the high-cost placebos are more effective than low-cost placebos.
• Cognitive Science: Toshiyuki Nakagaki, Hiroyasu Yamada, Ryo Kobayashi, Atsushi Tero, Akio Ishiguro, and Agota Toth for discovering that slime molds can solve puzzles.
• Economics: Geoffrey Miller, Joshua Tybur, and Brent Jordan for discovering that a lap dancer’s ovulatory cycle affects the tips she earns.
• Physics: Dorian Raymer and Douglas Smith for mathematically proving that a heap of hair or string will inevitably tangle itself into knots.
• Chemistry: Sharee A. Umpierre, Joseph A. Hill, and Deborah J. Anderson for demonstrating that Coca-Cola is an effective spermicide, and Chuang-Ye Hong, C.C. Shieh, P. Wu, and B.N. Chiang for discovering that Coca-Cola is not an effective spermicide.
• Literature: David Sims for his study "You Bastard: A Narrative Exploration of the Experience of Indignation within Organizations.”

The 2008 Ig Nobel Prize Winners [Improbable Research]