# Julie Trotter Back to [[Topics/Climate Change Science and Policy Debate/Climate Change Science and Policy Debate|Climate Change Science and Policy Debate]] · [[Topics/Climate Change Science and Policy Debate/Research and Evidence|Research and Evidence]] **Role:** Geochemist (conodont thermometry); lead author of Trotter et al. 2008 on Ordovician cooling. - Geochemist; affiliation at the time was CSIRO (Australia) ⚠️ (from memory; current post not checked). - **Trotter et al. 2008, "Did Cooling Oceans Trigger Ordovician Biodiversification? Evidence from Conodont Thermometry"**, *Science* 321:550 ([doi](https://doi.org/10.1126/science.1155814)). Oxygen isotopes in conodonts suggest tropical seas cooled from ~42°C in the Early Ordovician to modern-like ~23°C by the Middle Ordovician, alongside the Great Ordovician Biodiversification Event. - Relevance: the biggest Paleozoic diversification tracks cooling, not high CO₂ per se. - Appears in: [[Users/@PeterDClack/Post Analyses/Post Analysis - PeterDClack on High-CO2 Epochs and Biodiversity (2026-10-23)|Oct 23 high-CO₂ epochs analysis]].