human sexuality

NON-HUMAN ANIMAL CHECK-IN

SEXUAL CHARACTERISTICS


BLUESTREAK CLEANER WRASSE

  • All females in the species can change to males.

  • The most dominant female in a group is the one that changes sex to become male.

  • There is typically one male per group at any given time.

  • If the male dies or is challenged by a female, a new female can take over as male.

  • A challenged male has the ability to revert back to being female.

  • The transition from female to male takes approximately two hours.


CLOWN FISH

  • Clownfish are born male and are not sexually reproductive at birth.

  • The largest and most dominant clownfish becomes female.

  • The next largest clownfish becomes the sexually reproductive male.

  • Smaller clownfish residing within the anemone remain as underdeveloped males.

  • If the female dies, the reproductive male undergoes a sex change to become female.

  • The largest of the underdeveloped males develops into the new reproductive male.


CHANGING SEX

Types of Sex Change

  • Protandry:

    • Refers to the phenomenon where individuals born as males can change to females.

  • Protogyny:

    • Refers to the phenomenon where individuals born as females can change to males.

  • Gonochoristic:

    • This is a term used to describe species whose sex remains fixed and does not change throughout their lifespan.


FUN FACT: RETRONYM

  • Retronyms are terms that are created when a new opposing concept emerges.

  • Example of Retronym:

    • The word “homosexual” was coined first, leading to the later emergence of the term “heterosexual.”

    • Similarly, the term “transgender” was introduced before the term “cisgender” appeared.


WHY CHANGE SEX?

  • Changing sex can be beneficial due to evolutionary fitness, which relates to the likelihood of survival and successful reproduction.

  • Traits that enhance survival and reproductive success are more likely to be passed on to future generations, becoming predominant traits over time.

  • Reproduction is noted to be physiologically “expensive.”

  • By changing sex, individuals can potentially increase their fitness in the context of their environment.