In the biological sciences, a hermaphrodite is an organism that possesses both male and female reproductive organs. This condition is a normal part of the life cycle for many species across the plant and animal kingdoms. It allows for varied and resilient reproductive strategies in organisms that might be sessile or have difficulty finding mates.
Hermaphroditism in the Animal Kingdom
In the animal kingdom, hermaphroditism appears in two primary forms: simultaneous and sequential. Simultaneous hermaphrodites, such as earthworms and many snails, possess functional male and female reproductive organs at the same time. During mating, two earthworms align and exchange sperm, with each individual fertilizing the other’s eggs.
This reproductive strategy provides a significant advantage, especially for species that are slow-moving or live in low-density populations. By being able to function as either a male or a female, any two mature individuals of the same species can reproduce. This effectively doubles the chances of a successful mating encounter.
Other animals are sequential hermaphrodites, meaning they change their sex at some point in their lives, a change that can be triggered by social cues or reaching a certain age or size. One form is protandry, where an organism is born male and later changes to female. Clownfish are a well-known example; they live in small, hierarchical groups within a sea anemone, consisting of a large breeding female, a smaller breeding male, and several non-breeding males. If the female dies, the dominant male will change sex to become the new breeding female.
The opposite pattern, protogyny, involves an organism starting life as a female and changing to a male. This is common in fish like the bluehead wrasse, which often live in harems with a single large male and multiple smaller females. Should the dominant male be removed from the group, the largest female will undergo a sex change, developing male organs and taking over the reproductive role within a matter of weeks.
Hermaphroditism in Plants
For a vast number of flowering plants, hermaphroditism is the standard condition. These plants are often described as having “perfect flowers,” which means a single flower contains both male reproductive parts (the stamens, which produce pollen) and female reproductive parts (the pistils, which contain the ovules). Roses, lilies, and tomatoes are common examples of plants with perfect flowers.
The presence of both reproductive structures within one flower allows for the possibility of self-pollination, where pollen from the stamens fertilizes the pistils of the same flower. This can be an effective reproductive strategy for stationary organisms, as it does not rely on external pollinators like insects or wind. Many plants, however, have developed mechanisms to favor cross-pollination, where pollen is transferred between different individual plants to increase genetic diversity.
Some plant species have evolved strategies that separate male and female function over time, a process known as dichogamy. In these cases, even though a flower has both parts, they mature at different times. This temporal separation encourages cross-pollination by ensuring that the flower cannot fertilize itself.
The Term in Relation to Humans
The term “hermaphrodite” is considered outdated, inaccurate, and offensive when applied to human beings. Historically, it was used in medical literature, but it has since been replaced by the term “intersex.” The primary reason for this change is that the biological definition of a hermaphrodite—an organism with two complete and functional sets of reproductive organs—is not biologically possible in humans.
The correct and respectful term is “intersex,” which is an umbrella term for a wide range of natural variations in sex characteristics. A person who is intersex is born with reproductive or sexual anatomy that does not fit the typical binary definitions of female or male. These variations can appear in a person’s chromosomes, gonads (ovaries and testes), or genitals. There are over 40 documented types of intersex variations, highlighting a broad spectrum of human diversity.
Intersex traits may be apparent at birth, or they may become noticeable during puberty or even later in adulthood. In some cases, a person may not know they have an intersex variation unless it is discovered through medical imaging or other procedures for unrelated reasons. It is important to understand that being intersex is a natural variation in human biology, not a medical disorder. Using precise and respectful language, like “intersex,” is a way to acknowledge this diversity and move away from outdated and harmful terminology.