When two events (call them A and B) are Mutually Exclusive it is impossible for them to happen together: P(A and B) = 0. The probability of A and B together equals 0 (impossible).
Answer Wiki. Strauss & Howe, the social historians known for pioneering generational theory[1], would say that Gen X (the 13th generation) and Gen Y (the millennial generation) each have the traits of their corresponding generational archetypes. Generation X is generally used to refer to people born in the 60s and 70s. According to Strauss & Howe, it is a Nomad generation, an archetype they share with the Lost Generation of the 1890s and 1900s. Both generations are characterized by a disaffected attitude and general disdain for everything that came before.
The sex chromosomes of mammals have evolved over millions of years, originating from two identical chromosomes. Now, males possess one X and one Y chromosome and females have two Xs. The presence or absence of the Y chromosome is what determines sexâthe Y chromosome contains several genes key to testes formation. But while the X chromosome has remained large throughout evolution, with about 2000 genes, the Y chromosome lost most of its genetic material early in its evolution; it now retains less than 100 of those original genes.