Not true, there is evidence of people being born with variations as long as there is recorded history.
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Earliest Evidence: Ancient Mesopotamia (c. 3000–2000 BCE)

The gala (Sumer) and later galli (Akkadia, Greece, Rome) were priests devoted to goddesses such as Inanna/Ishtar and Cybele. These individuals were assigned male at birth but adopted feminine clothing, speech patterns, and social roles, and in some cases underwent ritual castration. Their existence is well‑documented in cuneiform texts and classical accounts, making them the oldest clearly recorded gender‑variant group in human history.
Even Earlier Archaeological Evidence (7000–2500 BCE)

While not tied to named individuals, archaeologists have found Neolithic and Bronze Age figurines from the Mediterranean that depict dual‑sex or third‑sex bodies—figures with both breasts and male genitalia, or with intentionally ambiguous sex characteristics. These artifacts suggest that gender variance was recognized symbolically thousands of years before written records.

Another early example is a burial near Prague (c. 2900–2500 BCE) in which a person genetically identified as male was interred in a traditionally female burial position and grave goods, which some archaeologists interpret as evidence of a third‑gender or transgender identity.
Other Early Recorded Gender‑Variant Groups

Several ancient cultures documented individuals who lived outside binary gender roles:

- Scythian enarei (c. 400 BCE): Androgynous priests described by Hippocrates and Herodotus as performing women’s work, speaking like women, and sometimes undergoing bodily modification.

- Two‑Spirit people in many Indigenous North American societies, whose traditions predate written records but were documented by early European observers.

- Hijra communities in South Asia, with evidence of third‑gender roles going back over 3,000 years.

These examples show that gender diversity is not a modern phenomenon but a longstanding part of human societies.

Kathoey — Thailand’s long‑standing third gender:

Kathoey (กะเทย is the Thai term often translated as “transgender woman,” “third gender,” or historically “ladyboy.” The concept predates modern Western ideas about gender by centuries.

Key points about the tradition:

- Historical presence: References to kathoey appear in Thai literature and folklore going back hundreds of years.

- Cultural role: Kathoey have traditionally been visible in entertainment, performance, and certain ceremonial roles, though social acceptance has varied over time.

- Not identical to Western categories: The term blends identity, gender expression, and sometimes sexuality in ways that don’t map perfectly onto modern LGBTQ+ terminology. Kathoey is a culturally specific gender category that blends identity, expression, and sexuality in ways Western LGBTQ+ terms keep separate.

Thai culture tends to see gender variation as part of the natural order. many Thais grow up seeing kathoey as simply one type of person who exists. Not a mistake, not a taboo, just part of the human landscape. This doesn’t mean universal acceptance, but it does mean visibility and familiarity.
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Pre‑modern Thailand didn’t use biological‑assignment language at all. Traditional Thai society did NOT categorize people using concepts like:
- “assigned female at birth”
- “assigned male at birth”
- “biological sex”
- “sex assigned at birth”

These are Western frameworks that grew out of:
- medicalization of sex (19th–20th century)
- feminist and queer theory (1970s–1990s)
- trans and intersex activism (1990s–2000s)

Thailand historically used social gender, not medical sex, as the primary category. People were understood by:
- how they lived
- how they dressed
- how they spoke
- their social role
- their relationships

Not by chromosomes or birth assignment.

So actually, they recognized people being born with variations for hundreds of years, while your 'Western framework' of sex is only RECENT.
Just another ignorant American, who thinks there was no history, before the few decades that he can remember.