Life begins with a single fertilized cell that gradually transforms into a multicellular organism. This process requires ...

Insect wings represent a pivotal evolutionary innovation that has underpinned the remarkable radiation of the Insecta. This field, at the intersection of evolution and developmental biology (evo-devo) ...

"This volume is printed, after the author's death, as a memorial by his instructors, pupils, and friends in Princeton, Baltimore, and elsewhere. It consists of his thesis, reproduced from the copy ...