Enlarge / The black and golden bumblebee, Bombus auricomus, is typically found in grasslands in the Great Plains and eastern states. (credit: alle12 via Getty) When ecologist Rachael Winfree first began studying bees 25 years ago, she happened upon a surprise: a species of plasterer bee in the New Jersey Pine Barrens, not seen in 50 years and suspected to have gone extinct.