She has worked in Manu since the beginning of her dissertation in 2004 at the University of Florida. Her research has focused on aspects of elevational ranges in tropical birds, including relationships between bird and vegetation communities and the influence of species interactions on range limits. Following her PhD, Jill held a postdoctoral position in the Biodiversity Research Centre at UBC before beginning as a professor. Her lab continues to study aspects of diversity and distributions, with a focus on ecology and evolution of tropical birds.