weigh

Image of a Mexican Jay selecting peanuts from www.sci-News.com I just listened to a neat podcast from Scientific American's Karen Hopkin in which she described a new study published in the Journal of Ornithology that suggests Mexican Jays (Aphelocoma ultramarina) pick which peanut to eat only after literally weighing their options. The researchers modified some peanuts to remove the contents. The Mexican Jays were then offered unmodified nuts along with the empty shells. Perhaps not surprisingly, the birds snubbed the empty shells. Rather, they only chose shells that contained nuts. In…