The Mendelian polymorphism in leaf shape in I. hederacea has been known for some time. Work by Kerry Bright Emlen and Mark Rausher investigated the maintenance of this polymorphism in the SE USA (no idea why the Wiley stock image is of out of focus birds):
onlinelibrary.wiley.com/doi/full/10....
Leaf shape is one of the most variable plant traits. Previous work has provided much indirect evidence that leaf-shape variation is adaptive and that leaf shape influences thermoregulation, water bal...
