A hieroglyph engraved over her head reads Ix Tzutz Nik, or "Lady Completion Flower," a name that shows up in several other artifacts from this period.
"I think this is a reference to a historical queen of Tikal and princess of Rio Azul, both very important kingdoms in the Early Classic period of the Maya lowlands," Freidel said.
But the woman pictured could have been a mythical figure, some archaeologists say.
"Gods also wore their names in their headdresses in Maya art," Calgary's Reese-Taylor said. "It is equally plausible that this monument names not a historical figure but rather a female deity."
Or Ix Tzutz Nik could have been both a historical figure and a deity. The lines between the human and the divine were blurred in ancient Maya culture. Many monuments depict historical rulers as gods.
The stela measures two meters (about six feet) high and one meter (about three feet) wide. Its inscriptions have been seriously damaged, likely as a result of an attack against the city.
Sometime between A.D. 550 and 650, however, the Maya reclaimed the monument and reburied it with great ceremony near the city's temples.
Researchers believe the burial was meant to honor the individual whose image was carved on the monument. Reburials are usually reserved for monuments that depict founders or important kings. An infant's bones were also found at the site.
"We always knew that royal women were important in Classic Maya society, but in Early Classic times they seemed to be more in the background," said Peter Mathews of La Trobe University in Australia, a member of the research team.
"Assuming our interpretation is correct, Lady Tzutz Nik must have been quite formidable," he said.
The Maya: Multimedia Specialists
The carving's focus on the head and the headdress alone is unusual, the archaeologists say. Most stelae images focus on entire human figures.
The carving is also done in a unique form that borrows from many independent art styles.
"It really comes across as a sort of hybrid form that invokes a wide array of imagery," said Julia Guernsey, a professor of pre-Columbian art history at the University of Texas at Austin who studied the portrait.
Guernsey believes the stela could have formed a stylistic "bridge" between different types of monuments.
"This stylistic fluidity raises fascinating questions about the range of inspiration that artists of this period drew upon, the possibility that artists truly were multimedia specialists who applied their talents to many different types of monuments," she said.
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