1. Introduction

Two major kinds of intercourse chromosome systems occur in vertebrates, XX female/XY male (e.g., individual and salmon) and ZZ male/ZW female ( wild wild birds and snakes). Just exactly How these functionally essential chromosomes evolve is an interest for debate for longer than a hundred years, considering that the finding associated with very first intercourse chromosomes within the belated 1800s 1–3. (más…)