What if the Maya civilisation declined because of climate change? At a time when humanity and the planet are threatened by the effects of global warming, a study published in Quaternary Science Reviews on ancient human faeces from the Maya population of Itzan reveals the link between climate and the demographic evolution of the Maya civilisation. Enough to make us sweat...
Faeces, a new relevant analysis tool
Yes, when we say 'faecal matter analysis,' we are talking about excrement, and in this case, that discovered near the Itzan archaeological site in northern Guatemala. The researchers analysed 'stanols,' the organic molecules present in human and animal faeces, from samples found at the bottom of a lake near the ancient Maya city.
In fact, organic matter is proving to be very useful from a research point of view. One of the authors of the study says:
It's a new tool to look at changes that might not be visible in the archaeological evidence, because that evidence may never have existed or may have been lost or destroyed since then.
And the results of the study can attest to the effectiveness of the method.
An earlier presence than archaeologists thought
So what does this analysis reveal? Several elements discovered confirm or undermine certain scientific theories on the dating of the arrival of the Maya presence. For example, the fact that the city of Itzan was inhabited more than 650 years before archaeology had first determined. This is proof that faecal matter can be used to supplement the research work based on the evidence present on the ground.
The authors were also able to detect 'a population peak' in 1697, a date that corresponds to the attacks of the Spanish colonists on the last Maya fortresses. This discovery suggests the hypothesis that the city of Itzan may have hosted numerous war refugees.
Climate change, the cause of the decline of the Maya?
The study also clearly establishes the phases of decline of this extraordinary civilisation. The local Maya population would have undergone three phases: the first between 1,350 and 950 BC, the second between 90 and 280 AD and finally the last between 730 and 900 AD. The authors of the study correlated these 3 episodes of demographic decline with periods of extreme drought, but also of extreme humidity.
Peter Douglas, one of the study's authors, says:
By connecting the evidence of climate and demographic change, we can begin to see a clear link between rainfall and the ability of these ancient cities to maintain their population.
It is important for society as a whole to know that there were civilisations before us that were affected by and adapted to climate change. By connecting the evidence of climate and population change, we can begin to see a clear link between rainfall and population maintenance.
Can we draw a parallel with current climate change?
At a time when our planet is undergoing major climate change, we certainly have a lot to learn from the Maya and their adaptations, successful or not, to climatic conditions.
However, the parallel between our two civilisations must be put into perspective. The impact of the Maya on the climate and the planet as a whole was of course less (the word is weak) than what human activities and the system of exploitation of nature that has been in place for more than two centuries have done.