Anthropologist claims hand positions on 1,300-year-old Maya altar have a deeper meaning

The Maya used "sign language" on an altar around 1,300 years ago, and these signs may represent important dates in the Maya Long Count Calendar, a new study claims.

"This is the oldest text where, to my knowledge, anyone has been able to show that there's a real, well-defined" script using hand signs that's on par with other kinds of writing study author Rich Sandoval, a linguistic anthropologist at Metropolitan State University of Denver, told Live Science. "Other researchers and I are pretty confident in saying that the conventions of these hand signs are rooted in sign language."

However, not everyone agrees with Sandoval's interpretation, and one expert calls it "implausible."

In the study, published March 8 in the journal Transactions of the Philological Society, Sandoval analyzed Altar Q, a late-eighth-century rectangular Maya stone altar from Copán, an archaeological site in Honduras. Altar Q's intricately sculpted four sides depict a total of 16 Copán rulers, each with specific hand positions, as well as hieroglyphs.

Researchers have studied Altar Q since the mid-1800s, and now Sandoval — who calls it "one of the most storied artefacts of Ancient Mesoamerica" in his study — writes that we can learn more about this Classic period (A.D. 250 to 900) stone carving by looking at the rulers' hands. In fact, he noted, rulers have particular hand positions in much of Maya art.

"Almost anywhere you see [Maya] hieroglyphs, you see a figure, oftentimes in the middle, at least one figure, sometimes multiple figures, holding very unique hand forms," Sandoval told Live Science in a voice note. "So I have deciphered these hand forms as hand signs with very specific meanings."

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His interpretation suggests that the Maya, whose civilization in parts of southern Mexico and Central America thrived during the Classic period, had a writing system that used two written scripts, Sandoval explained.

"Many researchers previously thought that the hieroglyphic script was the only script of the Mayan writing system," he said. His research shows that "there are two scripts to the writing system," Sandoval added, "so it's a lot more complicated than we thought."

Maya writing system

The known Maya writing system consists of over 1,000 hieroglyphs representing words and syllables, many of which are still undeciphered or poorly understood. Because Altar Q features both hieroglyphs and hand signs, Sandoval used it as a sort of Rosetta Stone — an ancient Egyptian decree translated into three ancient scripts. However, Sandoval thinks that, unlike the Rosetta Stone, the hand signs on Altar Q communicate different types of information than its hieroglyphs, meaning they are not translations of each other.

According to the study, the hand signs on Altar Q's east, west, south and north sides, or panels, represent the dates 9.0.2.0.0 (Nov. 27, 437), 9.19.10.0.0 (April 30, 820), 9.16.13.12.0 (Oct. 21, 764), and 9.17.5.0.15 (Jan. 7, 776). For these dates to make sense, it's important to understand how the Long Count Calendar works.

Long Count Calendar dates are represented by five "blocks" of days separated by periods. From left to right, these blocks are called b'ak'tun, k'atun, tun, uinal and k'in. The Long Count date 9.19.10.0.0, for example, represents nine b'ak'tuns, 19 k'atuns, 10 tuns, zero uinals and zero k'ins. One k'in is one day; one uinal is 20 k'ins, or days; one tun is 18 uinals; one k'atun is 20 tuns; and 1 b'ak'tun is 20 k'atuns, or 144,000 days. The Maya believed 13 b'ak'tuns (13.0.0.0.0) made up one full cycle of creation. Dec. 21, 2012, marked the end of the cycle that began Aug. 13, 3114 B.C.

It was already known that Altar Q's hieroglyphs, in their description of a 64-day ritual, imply the use of the Long Count Calendar. The start date of this ritual aligns with a period ending — a Long Count date that ends with at least two zeros, representing an important step in the calendar. As experts had also previously noted, the hieroglyphs indicate that the Copán dynasty started and ended roughly at the beginning and the end of the ninth bak'tun — yet another reference to the Long Count Calendar.

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Sandoval, however, highlighted an oddity. There were no Long Count Calendar dates expressed directly anywhere on the altar's hieroglyphs, which was highly unusual for a royal Maya text.

As for the hand signs themselves, the anthropologist focused on each of the 16 rulers' free hands. (Most of them are holding something in the other.) By comparing the 16 hand signs to the hieroglyphs, he noted two crucial features: that two distinct hand signs look like known hieroglyph variants of the number zero, and that their patterns of distribution with respect to the other hand signs are similar to those of zeros in Long Count period ending dates.

Sandoval thus assumed that the two hand signs represent zeros and that the 16 hand signs make up four Long Count dates falling in the ninth b'ak'tun. "The implication is that each panel's hand signs encode the K'atun, Tun, Winal [an alternative spelling for uinal] and K'in values of a Long Count date, read from left to right," he wrote in the study.

As for the b'ak'tun value, Sandoval claims that it is represented by each panel's upper rim and the heads of the four rulers — a bar-and-dot configuration that looks like an upside-down hieroglyphic nine. Both the number 9 and the upside-down aspect are associated with death and the Maya underworld, according to the study.

Tying it all together

At this point, Sandoval returned to the hieroglyphs, which included dates written in Calendar Round, a different Maya Calendar system that deals with shorter cycles of time. He found a surprising prevalence of the number 16. For example, the coefficients of the Calendar Round dates for the first and last rulers' ascension to the throne and death each add up to 16.

"16 is the most important number on this thing," Sandoval explained. Further hints to the calendar dates included directional associations with nearby monumental texts and the assumption that each date had to be linked to the underworld.

Ultimately, he linked each long calendar date to an important event or situation. The east panel is the death date of the first ruler; the west panel is the death date of the last ruler; the south panel’s date is associated with the 16th ruler's patron deity, and the north panel's date comes 16 days after the start of Altar Q's 64-day ritual.

"The reason why I'm so confident in my initial decipherment here and why it was so convincing to the reviewers is that I have multiple lines of evidence that are independent of one another, but they all support the same finding," Sandoval explained. "They're kind of weak on their own, but together they serve as very strong support," he added. "The observations work as verification because they're not dependent on one another."

"Implausible" finding

The Maya writing system is incredibly complex; it uses the design of text and art to integrate two scripts, Sandoval said, adding that "it's a unique system in the world." Previously, he researched how speakers of Arapaho — a Native American tribe that had roots in what is now Wyoming, Colorado, Nebraska and Kansas — mixed sign language and speech.

Not everyone agrees with his conclusions, however. "It looks very implausible," Alexandre Tokovinine, an anthropological archaeologist with a specialty in Maya epigraphy at the University of Alabama who was not involved in the study, told Live Science. "Visual and textual data appear manipulated to fit the author's hypothesis."

Nevertheless, Sandoval suggested his partial decipherment will underpin future decryption efforts.

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