The goal of the paper presented by M. Meijers et al. is to present a new, large data set of stable carbon isotope analyses performed on carbonates from late Miocene to Holocene sites in Anatolia. By combining their analyses with previously published carbonate d13C data, as well as published paleoclimate estimates from the region, the authors demonstrate secular changes and restructuring of paleofloral communities since ~10 Ma. Despite being a hotspot of projected anthropogenic climatic change, the evolutionary and climatic processes that shaped terrestrial ecosystems in the northeastern Mediterranean over the last 10 million years remain largely elusive. Whereas the expansion of C4 grasslands is well documented in regions such as eastern Africa and southern Asia, the dynamics in western Eurasia remain poorly understood. This gap in knowledge is critical for our understanding of how terrestrial ecosystems respond to large climatic shifts over geological timescales. In this manuscript, we present the first comprehensive stable carbon isotope record of pedogenic carbonates from Anatolia (Türkiye), spanning the last ten million years. Our results reveal that C4 grasslands in this region emerged during Late Miocene Global Cooling, simultaneously with southern Asian localities. Our study offers a unique perspective on a striking and largely unexpected feature: the permanent return to C3-dominated vegetation during the Early Pliocene – a phenomenon not observed elsewhere. We propose that this reversal to C3 vegetation was driven by regional hydroclimatic changes, in particular by a transition in rainfall seasonality, from a summer-dominated precipitation regime to a Mediterranean-style winter precipitation regime.

This manuscript introduces an innovative method for identifying cryptotephra in Antarctic ice cores, which could lead to significant new findings at Mount Brown South (MBS) and throughout Antarctica. The manuscript describes the identification of two new cryptotephra horizons in the MBS ice core from Wilhelm II Land in Antarctica. These cryptotephra originate from the mid-1980s eruptive period of Mt. Erebus and the cataclysmic 1991 eruption of Cerro Hudson. These two tephra horizons are an important addition to the East Antarctic tephrochronological framework. The findings of this study challenge previous assumptions about transport trajectories and pathways and satellite-era ice core chronologies, offering new insights into atmospheric circulation dynamics.