 The last universal common ancestor, Luka, was the first single-cell organism that all other life forms descended from. It had both a metabolism and an evolvable genome, which allowed it to pass down its traits to future generations. The genome contained parasites, which are now found in every living thing. These parasites can be thought of as eugenetic vampires, because they take resources away from the host without providing any benefit. However, these parasites also provide an advantage by allowing the host to adapt more quickly to changing environments. In this paper, the authors proposed a new model of nested parasitism, where multiple parasites work together to form a complex system that allows hosts to survive and adapt to their environment. This article was authored by Bernard Conrad, Christian Acelli, and Magnus Piravino.