What do hermaphroditic snails, gender role reversal in primates, and the ability to change sex have in common? They’re just a few examples of the wild and wacky world of gender and sexuality in the animal kingdom! While humans may have a complex understanding of gender and sexual identity, animals present diverse gender expressions that will blow your mind.
So, buckle up and get ready to explore everything from transgender-like behaviors to full-on gender-bending in our furry and scaly friends. Let’s dive in and answer the age-old question: Can animals be transgender?
At a glance:
Some animals can change their sex as needed. For example, species of fish, such as wrasses and clownfish, can change their gender from female to male or vice versa. Hermaphroditic snails can also switch between sexes as needed, and some amphibians, such as the southern leopard frog, can change their sex in response to environmental factors.
Defining Transgender in Humans
Before diving into whether animals can be transgender, let’s first define what we mean by the term. In humans, being transgender means that a person’s gender identity does not match the sex they were assigned at birth. This means that someone assigned male at birth may identify as female or vice versa.
Transgender in the Animal Kingdom
In the animal kingdom, gender and sex are not always the same thing. In many species, biological sex is not as simple as male or female. For example, some species have hermaphroditic individuals, meaning they have both male and female reproductive organs. Other species, like clownfish, have individuals that can change their sex from male to female or vice versa.
Also see: Do Animals Know Their Gender?
Quick Examples of Transgender Behavior in Animals
While animals do not have the same complex gender identities as humans, there are examples of transgender behavior in the animal kingdom. Here are some examples:
- Male spotted hyenas are born with female-like genitalia and are raised as females until they reach sexual maturity. At that point, their testes descend and start producing male hormones, leading to a masculinization of their behavior.
- Some male birds will perform courtship displays and act like females to get closer to a female and mate with her.
- Female Japanese macaques have been observed mounting other females to establish dominance or reduce stress.
These are some quick things to remember as I review specific animals and their transgender traits. Now let’s get into each animal below with some more behavioral facts.
Animals That Can Change Their Gender
| Animal Species | How They Change Gender |
|---|---|
| Clownfish | From female to male or vice versa, triggered by social cues |
| Wrasses | From female to male or vice versa, triggered by environmental cues |
| Hermaphroditic Snails | Switch between male and female reproductive organs |
| Southern Leopard Frog | From male to female or vice versa, triggered by environmental factors |
| Parrotfish | From female to male, triggered by social cues and changes in the environment |
| Garter Snakes | From male to female, triggered by population density |
Clownfish
Clownfish became well-known because of the movie Finding Nemo. They are fishes with a color of bright orange with three white bars.
Clownfish are sequential hermaphrodites, which means that they are born with one sex, but they can switch sex if needed.
Female clownfish are more dominant than male clownfish. But when the female clownfish dies, the female clownfish’s favorite male will be the one who will lead the school.
Females are usually the ones who lead the school. So to preserve this hierarchy, the male clownfish that have been chosen changes his sex to female. His size will increase, and have the ability to reproduce.
Wrasse
Wrasses are known as the opposite of clownfish. They have similar strategies to preserve the hierarchy of their school.
When the dominant male dies or leaves for a while to hunt, the female wrasse, who is the biggest, will quickly transform from female to male. The newly converted males are more aggressive in protecting their territory from predators.
Hermaphroditic Snails
Hermaphroditic snails can change their sex from male to female or vice versa. They possess both male and female reproductive organs and can produce sperm and eggs. Various factors, including the availability of mating partners and the surrounding environment, influence the decision to switch from one sex to another. For example, if a snail finds itself in an environment with few mating partners of its current sex, it may switch to the opposite sex to increase its chances of reproductive success.
Southern Leopard Frog
Southern Leopard Frogs can change their sex from male to female in response to environmental cues like temperature and population density. Specifically, if a male frog is exposed to a high population density or elevated temperatures during development, it may undergo feminization, where its testes regress, and ovaries develop.
This results in the frog changing its sex from male to female. Similarly, suppose a female frog is exposed to low population densities or cooler temperatures. In that case, it may undergo a process called masculinization, where its ovaries regress and testes develop, resulting in a change from female to male.
Parrotfish
Parrotfish have the same color as parrot birds. They are social animals that love to live in groups and may be found in schools with 40 individuals.
Even though most parrotfish are born female, they all possess both male and female genitalia. They are protogynous hermaphrodites, which means that females can be males whenever they want.
If the female parrot fish decides to switch gender, it will become larger than naturally born male parrotfish. The other awesome thing about this parrotfish is that they wear pajamas at night, and it is made from a cocoon of mucous.
Garter Snake
Garter snakes are common snakes in North America, Canada, and Florida. Some owners kept them as pets because they were harmless. However some garter snakes possess mild venom, but their venom is not dangerous to humans.
Garter snakes form a ball during mating. After the males hibernate and start to look for potential mates, they are naturally slow and tired. They take advantage of it by copying the female garter snake. Why?
This strategy is used for two strategic purposes. The first reason male garter snakes do this is to protect themselves from predators like birds because, as I have said above, they form a ball during mating. So the faux females will be covered by the males in an attempt to mate, and they are like inside a ball that keeps them safe from predators.
The second is raising their body temperatures quickly to make them more active than male garter snakes.
Animals That Can Identify as Having Transgender Traits
In this section, I’ll explore some animal behaviors that could be considered transgender-like, although it’s inaccurate to say that animals “identify” as transgender. These behaviors are often driven by instinct and hormones rather than personal identity, and not all scientists agree on whether they can be accurately described as “transgender.”
| Animal Species | Transgender-Like Behaviors |
|---|---|
| Spotted Hyenas | Born with female-like genitalia and raised as females until they reach sexual maturity |
| Black-Headed Gulls | Same-sex pair bonding and parenting |
| Japanese Macaques | Female mounting behavior and gender role reversal |
| Chickens | Male-to-female sex reversal due to genetic mutation |
| Deer | Hermaphroditic individuals with both male and female reproductive organs |
| Lizards (e.g. whiptail lizards) | Ability to change sex from male to female or vice versa |
| Bonobos | Same-sex sexual behavior and non-binary gender expression |
| Penguins | Same-sex pair bonding and parenting |
| Elephants | Same-sex sexual behavior and male-male bonding |
| Baboons | Male-to-female sex reversal due to adrenal gland malfunction |
| Rats | Same-sex sexual behavior and male-male bonding |
| Sheep | Male-to-female sex reversal due to genetic mutation |
| Dolphins | Same-sex sexual behavior and male-male bonding |
| Bearded Dragons | Male-to-female sex reversal due to environmental factors |
| Banana Slugs | Hermaphroditic individuals that can act as both male and female |
| Cuttlefish | Ability to change gender and coloration for courtship displays |
| Blackfin Goby | Ability to change gender in response to population dynamics |
| Frogs (e.g. southern leopard frogs) | Ability to change sex in response to environmental factors |
| Marsh Harrier | Male-to-female sex reversal due to hormonal imbalances |
| Sea Snails | Hermaphroditic individuals that can switch between male and female |
| Sea Bass | Ability to change gender in response to environmental factors |
Spotted Hyenas
Female spotted hyenas are born with a large clitoris that is often mistaken for a penis, and their mothers raise them as females until they reach sexual maturity. At this point, they experience a surge in testosterone that causes their clitoris to grow and become fully functional as a pseudo-penis used for mating, urination, and even giving birth. This pseudo-penis is so large that it can be mistaken for a male’s penis, leading to confusion about the animal’s true sex.
The male hyenas, on the other hand, have relatively small penis and are subordinate to the females in their social hierarchy. This inversion of traditional gender roles in hyenas challenges our understanding of gender norms in the animal kingdom. However, it’s important to note that while these behaviors may appear transgender-like, they are not driven by personal identity or self-awareness but rather by hormonal and social factors.
Black-Headed Gulls
These birds have been observed engaging in same-sex pair bonding and parenting, behaviors that were once thought to be exclusive to humans. Male-male pairs have been observed raising chicks together, suggesting they have taken on traditional female parenting roles. This challenges conventional gender norms in the animal kingdom and highlights the diverse range of gender expression in nature. (Source)
Japanese Macaques
Female Japanese macaques have engaged in male-typical mounting behavior and even gender role reversal. These behaviors challenge our understanding of gender identity in primates, suggesting that gender is not always binary in these animals. Additionally, male Japanese macaques have been observed mounting and engaging in sexual behavior with other males, which could be interpreted as non-binary gender expression.
Chickens
Some male chickens exhibit female-typical behavior and develop female physical characteristics due to a genetic mutation, resulting in male-to-female sex reversal. These individuals often have feminine physical characteristics, such as larger combs and wattles, and may even lay eggs. This challenge to traditional gender norms in chickens highlights the complex interplay between genetics and environmental factors in determining gender identity.
Deer
Some deer have been observed with both male and female reproductive organs, making them hermaphroditic. These individuals are often infertile but can still display gender ambiguity in their physical appearance and behavior. While not all deer display these traits, the existence of hermaphroditic individuals challenges our understanding of gender and highlights the complexity of sexual development in these animals. (Source)
Whiptail Lizard
The whiptail lizards can be found in New Mexico and Arizona. The entire population of the whiptail lizard is all females. They are the only species of lizards that have this kind of population.
They are long, slender lizards with pointed snouts, and they also have long tails. Giant spotted whiptails have longer tails than their bodies, and their tails can grow over afoot.
So how do these lizards reproduce if all of them are females? They reproduce eggs through parthenogenesis. The whiptail lizards mate with other females of its species. That is why they are also called lesbian lizards.
Bonobos
Bonobos have been observed engaging in same-sex sexual behavior and non-binary gender expression. Both males and females engage in sexual conduct with members of their sex, and individuals of both sexes engage in a variety of gender-atypical behaviors, such as male-female mounting and genital rubbing. These behaviors suggest that gender is not fixed or binary in bonobos and highlight the incredible diversity of gender expression in the animal kingdom.
Penguins
Some penguin species, such as the Adelie penguin, have been observed engaging in same-sex pair bonding and parenting. These pairs have been observed caring for eggs and chicks together and may even adopt abandoned chicks. This challenges traditional gender norms in the animal kingdom and highlights the complex social dynamics in penguin colonies.
Elephants
Both male and female elephants have been observed engaging in same-sex sexual behavior and male-male bonding. These behaviors challenge traditional gender norms in the animal kingdom and highlight the complex social dynamics that exist in elephant herds. Additionally, male elephants often form close bonds with one another that can last for decades, suggesting that gender is not always binary or fixed in these animals.
Baboons
Some baboons have been observed undergoing male-to-female sex reversal due to adrenal gland malfunction. Despite being genetically male, these individuals develop feminine physical characteristics and may even menstruate. This challenge to traditional gender norms in baboons highlights the complex interplay between genetics and environmental factors in determining gender identity.
Rats
Male rats have been observed engaging in same-sex sexual behavior and male-male bonding. These behaviors challenge traditional gender norms in the animal kingdom and highlight the complex social dynamics that exist in rat colonies. Additionally, male rats have been observed engaging in gender-atypical behaviors such as nest building and parental care, suggesting that gender is not always binary or fixed in these animals.
Sheep
In a case study of a sheep with male-to-female sex reversal due to a genetic mutation, the sheep exhibited feminine physical characteristics such as enlarged mammary glands and a lack of body hair. The sheep was also found to menstruate and exhibit female-typical sexual behavior.
Dolphins
Dolphins are brilliant and social animals, and both male and female dolphins have been observed engaging in same-sex sexual behavior. Male dolphins have been observed engaging in sexual conduct with other males and sometimes forming long-term pair bonds.
Female dolphins have also been observed engaging in same-sex sexual behavior and displaying masculine physical and behavioral traits. While the exact reasons for these behaviors are not fully understood, they challenge traditional gender norms in the animal kingdom and highlight the incredible diversity of gender expression that exists in nature.
Bearded Dragon
Bearded dragons have two chromosomes that determine their sex. Like other reptiles, their sex is determined by the environment’s temperature.
They can change their sex from male to female while inside the egg. Researchers have found that bearded dragons are fertile and can lay more eggs than the original female dragons.
The bearded dragons can also change their sex because of changing climates. When bearded dragons are exposed to hot temperatures, they are more likely to change their genders from male to female.
Banana Slug
Banana slugs can grow between six and eight inches and are color yellow, like the banana we eat. They are the largest species of slug.
Banana slugs are born with both male and female genitalia, and they belong to the hermaphrodite family.
During the reproduction process, the banana slug will find a mate that has a similar size to them. After successfully finding a mate, the two banana slugs will form a yin-yang shape and insert their penises located on their heads and impregnate each other.
Scientists have found that on some occasions, the banana slug can impregnate itself if it has not found a potential mate. Also, they have found that the banana slug sometimes gnaws its partner’s penis after copulation.
Cuttlefish
Cuttlefish are fishes that have three hearts, and they have a clear vision. They are also known as the chameleon of the sea, and there are 100 species of cuttlefish. Cuttlefish have eight arms, two tentacles, and a short lifespan.
Cuttlefish have an excellent strategy to get the girl that they like. To avoid messing up with other males that also try to attract the female cuttlefish they like, male cuttlefish can change one side of its body so that they will look like a female.
They show the female side to the other males, and the male side of their body is shown to the female they are talking to. The male rival will see two females, which will confuse him. Males use this sneaky tactic to convince the female to mate before the rival male discovers their tactic.
Blackfin Goby
The blackfin goby is usually between 10 to 200 feet under the ocean. They love to eat zooplankton and coral mucus. Blackfin goby has a tannish body with black dorsal and black tail fins.
There are many goby species, but only certain goby species can change sex. Even though the usual transformation is from female to male, sometimes it can go vice versa.
When the growth-rate advantage is in females, the female gobies change their sex into male. When gobies change their sex, their behavior also changes.
Females that become males might reduce their submissive behaviors and adopt the jerk personality of males.
Frog
There are 4,700 species of frogs worldwide, and every year all frogs go into hibernation. Frogs can jump 20 times their height and come in various colors.
Frogs can change their sex as well. Male-to-female sex changes happen to frogs living in suburban ponds, and the cause of this change is the increasing level of estrogen released in the water.
Scientists have found more female frogs than male frogs in suburban areas. However, scientists have found that the herbicide atrazine has been shown the cause of sex change in frogs.
Marsh Harrier
Marsh harriers can change sex, and they also can change their physical look. Most male marsh harriers change their appearances into females two years after birth.
Scientists believe marsh harriers change their appearances to prevent them from being attacked by other male marsh harriers.
Sea Snails
Sea snails change their sex so that they can survive. They can change their gender from male to female and vice versa. Sea snails are born male but become female after they reach maturity. The huger sea snail is usually the one who changes to a female.
Sea Bass
Sea bass is a fish living in the bottom of the sea (110-150ft) and inhabits rocky and sandy bottoms. They spend their life in dense kelp forests and near rocky reefs. Sea bass is usual in the U.S. They are protogynous hermaphrodites, which means they can change gender.
Researchers concluded that sea bass changes sex because of supply and demand. If female sea bass sense that there will be a decrease in the male population, females will change their gender to male real quickly.
Conclusion
While these behaviors may appear similar to human transgender identity, it’s important to note that they are not driven by personal identity or self-awareness but rather by hormonal and social factors. Nevertheless, they provide a fascinating glimpse into the complex and multifaceted nature of gender expression in the animal kingdom.
By understanding the diversity of gender expression in animals, we can gain a deeper appreciation for the complexity of gender identity and the importance of respecting individual differences.
