It is widely believed that climate played a major role in the decline of the Maya culture. Increasing droughts caused crop failures and food shortages. But as a study now reveals, the range of Maya crops also included some plant species that could still grow even in dry conditions, including the nutritious cassava roots. This suggests that the Maya could still support themselves during droughts.
For centuries, the Maya ruled over large parts of Central America. The remains of huge temple pyramids in the rain forests of Mexico and Guatemala still bear witness to their power. The ruins of the Maya sites also reveal that this culture already had a sophisticated and amazingly advanced system of hydraulic engineering. They used it to compensate for the uneven rainfall and the little water-storing subsoil in their region.
What caused the decline?
However, the question of what caused the decline of this once flourishing culture remains controversial to this day. Towards the end of the ninth century, most Maya cities began to depopulate and were eventually abandoned. The once mighty civilization fell apart. In addition to internal conflicts, the possible causes for this are primarily environmental factors. For example, some scholars argue that rapid population growth in Mayan cities led to increased deforestation and overexploitation of land, which in turn impacted the cultivation of food crops.
Another factor is the climate: there are now numerous indications that there was a change in climate and increased droughts in Central America at the time of the Maya decline. According to current hypotheses, this led to failed harvests and increased starvation. “However, one must first determine whether the meteorological drought also led to an agricultural drought severe enough to affect food production and lead to shortages,” emphasize Scott Fedick and Louis Santiago of the University of California at Riverside .
Not all Maya crops were susceptible
Closely related to this is the question of which crops the Maya grew and how large the spectrum of plants they used as food was. It seems clear that corn was of great importance as a staple food for the Maya. However, historical sources and the traditions of descendants of the Maya who are still alive today suggest that people in this region also switched to other plants: “Ethnographic studies of the plants used by today’s Maya in times of drought or food shortages show that many of them are so-called famine foods, which grow or be cultivated in the forest,” explain Fedick and Santiago. For their study, the researchers therefore examined which of the 497 plants used by the Maya still grew during drought and how nutritious they were.
It turned out that while corn and beans do not survive a short period of drought, the Maya would have had more than 400 other plants left in such a case. These include nutritious plants such as avocado, sweet potato, cassava, amaranth and some types of nuts and fruits. If the dry spell lasts longer and, for example, there is too little rain throughout the year, there would still be 108 plant species that could not be affected by this drought. “Compared to a year of normal rainfall, this represents a 69 percent decrease in edible plant parts and a 78 percent decrease in available species,” the scientists report.
Manioc and co as drought food
However: “Even in the most extreme drought situation – a case of the occurrence of which we have no evidence in the Maya period – 59 plant species would still be preserved for the Maya,” says Santiago. These species would survive even a severe multi-year drought. Among the plant food then still available would be palm hearts and cacti, but also 29 different roots and tubers. “Among the root plants with high drought resistance, cassava stands out,” say the researchers. Because their roots have a high calorie density and it is known that the Maya also cultivated this species intensively.
According to Fedick and Santiago, repeated droughts may well have affected Maya agriculture. But that’s probably not why people had to suffer from hunger back then. “So the oversimplified explanation that droughts led to a complete collapse of agriculture is probably wrong,” says Fedick. “Because our analysis suggests that the Maya had a large variety of alternative food crops available even in times of drought.” This does not rule out the fact that drought periods lasting several years have led to bottlenecks in the supply of the populous Mayan metropolises. Nevertheless, one must be careful not to automatically infer famine from meteorological droughts.
Source: University of California Riverside; Specialist article: Proceedings of the National Academy of Sciences, doi: 10.1073/pnas.2115657118)