Natural history of the narrow endemics Ipomoea cavalcantei and I. marabaensis from Amazon Canga sava
Some Ipomoea species are narrow edemics of the Carajás region in the State of Pará Brazil, and inhabit savannah-like Canga areas composed of lateritic rock (rich in Fe) that are surrounded by the forest. We looked at chloroplast and nuclear genetic markers to study the genetics of these two species. We observed that the Cangas provide strong selective pressure for speciation. See the paper here.