Archaeologists are commonly thought to only find durable artifacts like ancient ceramics, jewelry and gold, or occasional plant remnants or animal bones. Few suspect that it is common for archeologists to find human organs underground since they are so delicate. Recently, the scientific journal Proceedings of the Royal Society B reported the discovery of more than 4,400 preserved human brains that are 12,000 years old. These well-preserved brains were found around the world, and exhibit a striking resemblance to healthy, modern human brains. These discoveries have sparked increased fascination with preserved brains, and led to speculation regarding how they remained intact for such extended periods.

For some of these brains, Researchers concluded that the brains were preserved by different processes. They found that nearly 38 percent were dehydrated and that 30 percent were saponified, which is a chemical process that produces a preservative substance known as grave wax from fats in the body. Less than two percent were frozen, and less than 1 percent were tanned. However, more than 30 percent were preserved by an unknown process, which researchers are still investigating.

One possibility that they suspect is that the presence of certain substances, such as iron, at the archaeological sites might have triggered a preserving chemical reaction. These substances could make the brain tissue more stable, allowing it to keep its shape for thousands of years. Further research and analysis are necessary to get a better picture of how these brains were preserved, but advancements on these brains have been slow.

Part of the problem is that when conducting field research, these preserved brains can be easily overlooked or destroyed because they often have the same color as their surroundings. Currently, less than 1 percent of the preserved brains have been studied. Scientists and researchers are treasuring them because these brains are very unique. As forensic anthropologist Alexandra Morton-Hayward said, “If they’re precious, one-of-a-kind materials, then you don’t want to analyze them or disturb them.” In reality, these recent excavations have shown that preserved brains are not as uncommon as previously thought. These excavations not only yield interesting discoveries, but also signal to the scientific community that preserved brains are more readily available than assumed. With the fear that they are destroying a one-of-a-kind material gone, scientists are likely to utilize the brains for more study and analysis.