Archaeology and Climate Change– The Collapse of the Mayan Empire


Climate change is a hot button issue in today’s society. Rising sea levels, disappearing forests, and depleted ozone make headlines as indicators of a society headed towards death by its own hand. Many blame human activity; chlorofluorocarbons destroy the ozone layer, while carbon dioxide emitted by cars and factories causes a greenhouse effect that melts polar ice to and causes sea levels to rise.

While the evidence supporting climate change as a consequence of human activity is strong, it has its opponents. Many argue that global temperatures fluctuate often, and that recorded human history is not sufficient to draw any conclusions about the causality link between rising temperatures and human activity. How, then, do we deliberate between who is right and wrong? As it turns out, Archaeology can help.

picture 1 blog post 2

The Yucatan Peninsula was home to the Mayans until their sudden collapse either during the 8th or 9th century.

The Mayan people arrived in the Yucatan area sometime between 2600 and 1800 B.C.E., growing to 19 million before their collapse around the 8th century. What could have been the reason for a mass exodus of tens of millions from some of the most populated cities in existence at the time? Some propose disease, some foreign invasion; new evidence, however, points to climate change.


Researchers at Arizona State University analyzed archaeological data from the Yucatan Peninsula during the fall of the Mayans. Their findings: during this time, deforestation for agriculture coincided with a severe reduction in rainfall. Additionally, there was a large demand for wood to fuel fires that cooked the lime plaster that was a staple in Mayan construction; some experts figure that each square meter of cityscape required the destruction of 20 trees.

At Columbia University, researchers used data from the region to construct a computer model to simulate the conditions during the Mayan collapse. They found that cleared lands absorb more water, thereby reducing the presence of clouds and rainfall. Their model estimated that deforestation accounted for roughly 60 percent of the total drying that occurred in the area during the time in question (the other 40 percent was a naturally occurring drought).

picture 2 blog post 1

Large Mayan cities like Tikal (pictured above) became poor in the absence of trade, causing many to flee.


Drought on such a large scale in an area with such a high population density was catastrophic. Trade moved from overland routes through the heart of the Mayan civilization to sea-based routes around the peninsula. The Mayan cities relied on trade as a source of income, and the elite that ran those cities relied on it for power. Without trade, Mayan cities became poor and powerless. Peasants fled the cities to avoid starvation, leaving us with the ruins we see today.

The Mayans existed when human activity had done little to alter the earth. With no other external factors at play, deforestation was introduced, and the Mayan civilization collapsed shortly thereafter. This suggests that climate change can in part be blamed on human activity. The archaeology of climate change is important for this reason: the first step in fixing a problem is determining whether or not the problem actually exists. Archaeology and the Mayans have brought us one step closer to the answer.


Futher Reading

Modern Archaeology and Cancer


Cancer research is a hot topic in today’s medical community. Many of society’s best and brightest work tirelessly to eradicate cancer from world, developing new drugs, surgical techniques, and prevention methods. Curing cancer, however, is largely contingent on pinpointing its causes. This is where archaeology plays a role. Is cancer strictly a result of modern lifestyle, or was it present in ancient times? If it was, what were the rates at which cancer was contracted in different areas over different periods of time? Is there any overlap between the causes of cancer in the modern world and in the past? These are all questions archaeologists can answer.

Two colleagues at Manchester University, Rosalie David and Michael Zimmerman, have done extensive research on cancer in the past. They have searched for references to the disease in classical literature, looked for evidence in the fossil record and in mummified bodies, and even gathered data about other pathologies contracted in ancient times to establish a frame of reference with respect to modern times.[3] Their findings: cancer is man-made. In the journal Nature Reviews: Cancer, the two archaeologists reported a “striking rarity of malignancies in ancient physical remains” that might “indicate that cancer was rare in antiquity”[1][2]. Said Professor David, “There is nothing in the natural environment that can cause cancer. So it has to be a man-made disease, down to pollution and changes to our diet and lifestyle”[3].

Many disagree with the above viewpoint.  According to Cancer researcher Dr. Robert A. Weinberg, “There is no reason to think cancer is a new disease. In former times, it was less common because people were struck down midlife by other things.” Furthermore, the scarcity of evidence for cancer in David and Zimmerman’s research can be accounted for by a number of factors.

Mummified remains often retain soft tissue, and are promising prospects for evidence of ancient cancer

Mummified remains often retain soft tissue, and are promising prospects for evidence of ancient cancer

Cancer generally develops in soft tissue, which tends to disappear before archaeologists can find it. Additionally, there are large gaps in archaeological records. For a long time, archaeologists only collected skulls. There is no telling what sort of cancer evidence was present in discarded skeletons[1]. Recent findings, such as a 4,200-Year-Old case of breast cancer [4] and a skeleton with cancer from 3000 years ago,[5] suggest even further that cancer is not a modern phenomenon.

Figure 2 An X-ray of an early medieval man exhibiting signs of metastatic carcinoma--a cancer that begins in soft tissue but then spreads to bones

Figure 2 An X-ray of an early medieval man exhibiting signs of metastatic carcinoma–a cancer that begins in soft tissue but then spreads to bones

So is cancer a disease brought about by modern lifestyle choices? It appears as if the answer is both yes and no. As research continues to be done, it appears as if cancer was less prevalent in ancient times. While modernity has increased the incidence of cancer, it cannot be blamed entirely; says Dr. Weinberg, “Cancer is an inevitability once you create complex multicellular organisms and give the individual cells license to proliferate. If we lived long enough, sooner or later we would all get cancer.”[1] It appears as if archaeology has provided us with the following conclusion: cancer is not strictly a result of modern living, but there are still common lifestyle changes that need to be made in order to reduce its presence.







Further Reading