“…The Inland Northwest of the United States (Idaho, eastern Oregon and Washington, and portions of surrounding states) is a natural laboratory for the study of the MMCO due not only to the detailed paleoclimatic (Retallack 2007, Retallack 2009, Takeuchi et al 2007, Yang et al 2011) and paleoenvironmental (Bestland et al 2008, Harris et al 2017, Kohn and Fremd 2007, Sheldon 2003 records available in the region but also to the wealth of terrestrial fossil floras and faunas preserved there. These include the vertebrate faunas of the Mascall (Downs 1956, Maguire et al 2018), Sucker Creek (Scharf 1935, and Virgin Valley formations (Merriam 1911), which, along with other localities in the region, have served as the basis for several analyses of vertebrate macroecology (e.g., Badgley and Finarelli 2013, Calede et al 2011, Harris 2016, Maguire 2015, Orcutt and Hopkins 2013.…”