1 Evolution of leaf-cutter behavior in bees (Hymenoptera: Megachilidae) as inferred from total- evidence tip-dating analyses Victor H. Gonzalez1,2, Grey T. Gustafson2,3, and Michael S. Engel2,3,4 1 Undergraduate Biology Program and Department of Ecology and Evolutionary Biology, Haworth Hall, 1200 Sunnyside Avenue, University of Kansas, Lawrence, Kansas 66045-7523, USA. 2 Division of Entomology, Natural History Museum, 1501 Crestline Drive – Suite 140, University of Kansas, Lawrence, Kansas 66045-4415, USA. 3 Department of Ecology and Evolutionary Biology, Haworth Hall, 1200 Sunnyside Avenue, University of Kansas, Lawrence, Kansas 66045-7523, USA. 4 Division of Invertebrate Zoology, American Museum of Natural History, Central Park West at 79th Street, New York, New York 10024-5192, USA. *Corresponding author: E-mail:
[email protected] Running title: Systematics and evolution of leaf-cutter bees 2 TABLE OF CONTENTS Abstract……………………………………………………………………………………….…3 Introduction………………………………………………………………………………….…..4 Diversity and phylogeny of Megachilidae…………………………………………….…….6 Diversity and phylogeny of Megachilini……...................................................…….….……6 What is the genus Megachile?.................................................................................................7 Fossil record…………………………………………………………........…………………9 Material and methods………………………………………………………....………………....9 Taxon sampling……………………………………………………………………………...9 Morphological data…………………………………………………………………………10 Data compilation………………………………………………………………………..11