Extraction of Glycerol Dialkyl Glycerol Tetraethers (GDGTs) in the laboratory from sediment core samples, including drying and lipid extraction (personal photos). Two examples of GDGTs are shown. The type of molecule indicates whether the temperature was warmer or cooler. Example of an archaeal species that can produce GDGTs: Candidatus Nitrosopumilaceae from the phylum Thaumarchaeota. Picture credits: Dr. des. Rodrigo Martínez-Abarca/TU Braunschweig (adapted from Quin et al., 2016).

This image is part of: Doctoral Adventure: 400,000 Years of Climate Change. Please note the copyright of this image.