“…Despite it has a relatively small surface area (35,000 km 2 ), it contains over 3,000 plant species, several of which are endemic (Luteyn, 1999;Hughes and Atchison, 2015) and emerged as unique adaptations to extreme environments that evolved during the Andean uplift in the last five million years (Antonelli et al, 2009;Madriñán et al, 2013;Mutke et al, 2014). Unparalleled diversification rates across plant groups at these tropical "sky islands" (Sklenáø et al, 2014) has further been attributed to colonization by pre-adapted linages (Muellner-Riehl, 2019), and Pleistocene glacial cycling (Nevado et al, 2018;Perrigo et al, 2019;Rahbek et al, 2019) in the last 2.4 Myr that led to repeated periods of connectivity and spatial isolation (i.e., "species pump hypothesis"). Population fluctuations in concert with past glacial cycling indicate a general inability to adapt and a major role of range shifts (Martín-Bravo et al, 2010;Ronikier, 2011;Hazzi et al, 2018;Muellner-Riehl, 2019).…”