We are seeking PhD students to join our team working on the project entitled "Evolution of Thermal Traits in Insects: A Comparative-Ecological Approach," funded by the Estonian Research Council (2025-2029) and carried out at Estonia's leading research centre, the University of Tartu (https://www.ut.ee/en). The lab-wide project focuses on a macroevolutionary analysis of the evolution of thermal traits (such as the minimum suitable temperature) in insects. The ultimate aim is to evaluate the potential of insect populations to respond to ongoing climate change. The research will rely on a diverse set of methods, including meta-analyses of published data, analyses of geographical distribution patterns, and empirical work to collect comparable data on various insect species across Europe. Specific PhD projects will be tailored based on the research interests of the students. The work will be supervised by Prof. Toomas Tammaru (http://www.ut.ee/~tammarut) and other members of his team (https://zooloogia.ut.ee/en/content/chair-of-entomology-members-of-the-chair). Our group has a unique combination of interests and expertise, covering evolutionary ecology, advanced statistical methods, phylogenetic comparative analyses, and the taxonomy of insects, Lepidoptera in particular. You will experience a work atmosphere that combines the spirit of an old university town with a highly modern and international research environment. PhD studies in Estonia last four years, and publishing research papers is a requirement. PhD students receive competitive salaries, allowing them to work on their theses full-time while also taking some relevant classes. A successful candidate will have an excellent academic record, experience with statistical analyses, and an interest in evolutionary biology. Some experience and/or a genuine interest in the ecology, evolution, or taxonomy of insects would be an advantage. The candidate must have obtained their Master's degree by August 1, 2025. Enrolment as a PhD student will be on September 1, 2025. To apply, please send your CV and a motivation letter (200 to 300 words) outlining your experience and interests related to the subject to Toomas Tammaru (toomas.tammaru@ut.ee) before the end of February 24 (any time zone). The position is open to applicants of all nationalities. Toomas Tammaru (to subscribe/unsubscribe the EvolDir send mail to golding@mcmaster.ca)