Explore a mathematical lecture on Lambda-coalescents arising in populations with dormancy. Delve into a model of population evolution through spring, summer, and winter seasons, examining how dormant individuals wake and reproduce. Discover how early-waking individuals can lead to Lambda-coalescent genealogies, allowing multiple ancestral lines to merge simultaneously. Learn about the characterization of Lambda-coalescents in this framework, including the beta coalescent's role when wake-up rates increase exponentially. Investigate topics such as the Wright-Fisher Model, Kingman's Coalescent, Cannings models, and heavy-tailed offspring distributions. Gain insights into the genealogy of populations with dormancy and the classification of possible limits in this mathematical exploration of population dynamics.