The question of how many animal species exhibit LGBT behaviors and identities has been a topic of growing interest and study in recent years. While concrete numbers are difficult to pin down, research suggests LGBT behaviors and identities are more common across the animal kingdom than previously assumed. Some key points on this fascinating subject:
- Same-sex sexual behavior has been documented in over 1,500 animal species including mammals, birds, fish, reptiles, amphibians, and insects.
- LGBT behaviors serve a variety of purposes depending on the species including courtship, social bonding, parenting, and conflict resolution.
- Approximately 8% of rams exclusively partner with other rams over ewes. In some species same-sex pair bonding is more common than male-female pairing.
- Transgender behaviors have been observed in multiple species in which animals biologically one sex live and act as the other sex.
- The relative prevalence of LGBT behaviors varies greatly across species – from quite rare to nearly universal.
- The research field investigating LGBT behaviors in animals has rapidly expanded in the past 30 years as cultural views have shifted.
With thousands of animal species on the planet exhibiting a wide diversity of sexual behaviors, determining precise LGBT statistics remains challenging. But the research makes clear these behaviors are natural and common occurrences throughout the animal kingdom.
Documented Species with LGBT Behaviors
Scientists have documented same-sex sexual behaviors and LGBT identities in hundreds upon hundreds of animal species across a wide range of taxonomic groups:
Mammals
LGBT behaviors have been observed in numerous mammalian species including:
- Bonobos and chimpanzees (our closest genetic relatives)
- Dolphins
- Elephants
- Giraffes
- Lions
- Horses
- Bison
- Goats and sheep
In some mammal species, such as elephants and dolphins, the majority of individuals exhibit bisexual behavior.
Birds
Same-sex courtship and mating is common among birds including:
- Penguins
- Parrots
- Ostriches
- Ducks and geese
- Seagulls
- Pigeons
Some bird pairs form long-term same-sex bonds and build nests together each mating season.
Reptiles
Reptiles with documented LGBT behaviors include:
- Tortoises
- Geckos
- Lizards
- Snakes
In some lizard species, females pair in homosexual relationships that involve courting, long-term bonding, and nesting together.
Amphibians
Frogs and toads exhibit same-sex coupling behaviors. Some frog species also display transgender behaviors, such as male frogs adopting female identities and communicating as females.
Fish
Numerous fish species engage in same-sex courtship and spawning behaviors, including:
- Angelfish
- Parrotfish
- Guppies
- Wrasses
- Blennies
In some fish species, the majority of sexual interactions are between two males rather than a male and female.
Insects
LGBT behaviors occur among many insect species including fruit flies, beetles, butterflies, and dragonflies. Same-sex coupling has also been documented in multiple spider species.
Prevalence Rates Across Species
The relative prevalence of LGBT behaviors and identities varies greatly between animal species. Here are some examples:
- 8% of male sheep exclusively mate with other rams and refuse to mate with ewes.
- 20% of whale species have bisexual encounters.
- In some penguin colonies, nearly all penguin pairs are of the same gender.
- Up to 94% of male Galapagos tortoises engage in homosexual sex.
- Female Laysan albatross pairs outnumber male-female pairs by a ratio of 2 to 1.
- 1 in 5 black swan pairings are male couples.
While precise statistics remain elusive, these examples demonstrate LGBT behaviors encompass more than just a handful of exceptional cases. They are relatively common occurrences throughout the animal kingdom.
Purpose of LGBT Behaviors
Researchers have proposed various evolutionary explanations for why LGBT behaviors have developed across so many species:
Social Bonding
Same-sex coupling frequently serves to strengthen social connections and attachments between animals. Homosexual bonds help establish critical non-reproductive relationships.
Conflict Mediation
LGBT sexual contact helps resolve conflicts over status, resources, nesting sites, etc. It facilitates important conflict resolution between animals of the same gender.
Parenting
In some species, homosexual pairs mate with opposite sex partners but rear the offspring together. Same-sex parenting helps provide care for the young.
Courtship Practice
Younger animals commonly learn courtship skills by practicing with same-sex partners before mating with the opposite sex. It provides important experience for reproductive behaviors.
Population Control
LGBT behaviors may help regulate overpopulation and balance sex ratios within animal groups. It provides an evolutionary advantage for the species.
The purposes and advantages of LGBT conducts are quite nuanced and can vary significantly between different animal societies and environments. But the research clearly demonstrates these behaviors serve natural adaptive functions across species.
Transgender Behaviors in Animals
Transgender behaviors have also been documented in various animal species. This includes animals biologically one sex living as and reproducing in the role of the opposite sex. Some examples:
- Female spotted hyenas exposed to high testosterone levels during birth take on traditional male roles including mating with females.
- Some male wrasses transform into females if no female is present in their group. The males function fully as females and reproduce with male wrasses.
- Female lions will grow manes and begin acting like male lions when new males enter the pride. The females exhibit masculine behaviors to assimilate.
- Multiple animals including fish, birds, and insects directly switch their sex throughout their lives depending on social/reproductive needs.
This further demonstrates the diversity and fluidity of sexual behaviors, identities, and roles displayed across the animal world.
Research History on Animal LGBT Behaviors
For most of human history, LGBT behaviors in animals went unstudied or were consciously overlooked. As cultural attitudes have changed, scientific interest in documenting the phenomena has risen dramatically:
- First research study on animal homosexuality published in 1908 examining beetles.
- Scientific publications on LGBT animal behaviors numbered less than 1 per year pre-1990.
- Papers on animal LGBT studies increased to 20+ annually by early 2000s.
- Research on LGBT animals today continues growing exponentially.
- Over 1,500 species with LGBT behaviors now scientifically reported.
- Dozens of books published on the evolutionary origins and purposes of LGBT conducts in animals.
Researchers emphasize these behaviors are entirely natural aspects of animal complexity we are now beginning to objectively quantify and understand.
Conclusions
While statistics on precise percentages are limited, the research clearly demonstrates LGBT behaviors, identities, and roles occur naturally across a wide diversity of animal species. Same-sex pairing, homosexual bonding, bisexual conducts, and transgender behaviors have been extensively documented throughout the animal kingdom. These phenomena serve important evolutionary and social functions in various species. As cultural attitudes shift, scientific documentation of LGBT diversity throughout the animal world continues to rapidly proliferate. This highlights the biological normalcy and value of sexual fluidity in the natural world.