Why did Mexica priests have matted hair?

Professor Cecelia Klein (on our Panel of Experts - read her fascinating article on ‘How Mesoamericans viewed the cosmos’ by clicking on the link below) has shown that much in the world before the arrival of the Spanish in Mexico was made of natural materials that had to be woven and matted together to form structures such as the roofs of houses - and that the same applied to the physical form of the over- and underworlds. Various parts of simple Aztec/Mexica and Maya houses were literally bound together using twisted cords and vines - in the Aztec case, cords probably made of a wild twining grass called malinalli. Is it not significant that one of the twenty day/calendar signs of the Aztecs was malinalli (Pic 1)?

Pic 1: The Aztec calendar sign no. 12 Malinalli (Grass)

In the visible world on the earth’s surface, however, these become more ordered and braided - as in the case of the ‘stretched out’, interlaced, entwined roots of trees. Trees and housepoles, as Klein reminds us, ‘provided the chief support for the ancient weaver’s backstrap loom, and thus marked the implicit centre of the woven cosmos’. Notice the upright supports strengthening the plants entwined around them, growing out of the snake-framed earth in the Codex Tudela (Pic 3).

Pic 3: Plants and snakes, Codex Tudela, folio 68