If you have ever seen, or spent time with (or, God forbid, had to live with) a colicky baby, this will make perfect sense to you. It may not make actual sense, but when the baby is crying you don't think very straight.
Speaking at the first BAHFest in 2013, MIT grad student Tomer Ullman proposes that in ancient times, screaming babies were used to motivate armies to fight. Howling infants, he suggests, were probably attached in baby carriers to the backs of warriors to give the combatants "a natural adrenalin boost" as they surged into battle. In this way, he proposes, "infant stress vocalizations" became a weapon of war. The BAHFest is an annual gathering of science lovers, where totally inane ideas (Bad Ad Hoc Hypotheses, or BAHs) are proposed and defended using big words, insane charts and too many numbers.
Mr. Ullman's screaming baby hypothesis was voted best last year. Watch and you'll see why:
Thanks to Aatish Bhatia for showing me this.