While I was under the impression that I had a relatively well-rounded understanding of sex and its nuance, I’ve learned throughout this semester that I had only scratched the surface. Although I was aware of things like the existence of intersex individuals and the fact that some animals exhibit same sex behavior, there was so much more to these concepts and many more than the general knowledge that I had. The specifics of the dynamic nature of sex have been profoundly interesting to me and learning about the many variables that determine sex only made my definition of it more complicated. Not that it was a bad thing to learn that sex isn’t as simple as XX vs XY chromosomes, but rather it made me realize how little I actually knew about the subject. Soon my definition came to include not only sex chromosomes and genitalia, but also hormones, secondary sex characteristics, gonadal development, phenotypic characteristics, differences in brain activity, and more. Not only is sex dependent on so many characteristics, but it also has so much variability in its possible outcomes. While I had known that there were males, females, and intersex for anyone who didn’t fit neatly into those two categories, that simplification does an injustice to the broad variety of sex outcomes observed in nature. Not only are there other types of sex chromosomes than X and Y, such as Z and W, but sex can also be dosage dependent on certain hormones or influenced by environmental factors, or even influenced by parasitic species. It doesn’t help that a majority of the behaviors and traits of certain sexes in animals were swayed by biases held about sex in humans, causing us to miss so much more due to a confirmation bias. Sex behaviors in animals aren’t as simple as males are aggressive and uncaring while females are nurturing and coy. Those instilled beliefs prevent researchers from observing the fascinating variation in behaviors and traits across sexes and broadening our understanding of the evolution of sex across species. While I feel my knowledge of sex and gender throughout the animal kingdom has grown tremendously, I know I have still only seen the tip of the iceberg. The more I learn about the complexity of sex, the less I feel I know, though this isn’t a bad thing. Rather than feeling stupid or in the dark about the subject, I feel content in the fact that while I have learned a lot, I’ll never know every fact or aspect of the concept of sex. If anything, I feel that by broadening my understanding of what sex is, I’ve become more aware that sex isn’t something that can be easily summed up or described. I’m okay with not knowing everything and looking forward to learning more.