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This is Scientific American’s 60-Second Science, I am Cynthia Graber. This will just take a minute.

Western Mexico and countries on the west coast of South America had ancient relationships, involving trade in goods and culture. Now MIT students have analyzed¹ just how this communication and transportation system worked. The study was published in the journal of Anthropological² Research. First, the students recreated a raft, based on descriptions in European colonial writings. They successfully tested it on Boston’s Charles river. Then the students used computerized engineering design programs to test the raft size, weight, and cargo³ capacity. They had to develop a much more detailed⁴ design for the raft’s dimensions and what was available in the centuries-old drawings. But they didn’t stop at aerodynamics and hydrodynamics, they also delved⁵ into biology. Because shipworms can make a quick snack of South American balsa wood. A one way voyage would take between six and eight weeks.  So how long would a raft last on the journey before succumbing⁶ to shipworms? According to the students’ simulations, rafts could last two full round trips between Mexico and Indian countries, enough time for a vibrant⁷ exchange of goods and ideas.

Thanks for the minute for Scientific American’s 60-second Science. I am Cynthia Graber.