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Experts Disagree Over Which African Termite Mounds Are The Oldest

Termite mounds can be found in Africa, South America and Australia. Generally, different mound-building termite species use the same materials when building their mounds. These materials include various types of soil, such as ground clay, and termites use their saliva to make soil particles less firm and more pliable for building purposes. Termite dung is also important as a building material, as it makes a mound’s external surface firm, which protects the mound’s structure from harsh climatic conditions. Due to this hard surface, termite mounds can easily become fossilized, as hard mounds do not always degrade in response to erosion or soil accretion. However, researchers have had difficulty determining the age of fossilized mounds with acceptable accuracy. In fact, some researchers have claimed that some fossilized termite mounds, such as the Heuweltjies mounds located in South Africa, are not, in fact termite mounds at all; instead these land formations are dismissed as natural consequences of gradual erosion. Because of this disagreement, nobody can be sure which termite mounds are the oldest ever to found.

Not long ago, researchers traveled to the Miombo woodland area located within central Africa. This area contains numerous termite mounds that can reach ten meters in height and fifteen meters in width at the base. In order to accurately date these mounds, researchers gathered samples of soil from the mound’s central vertical axis. Researchers then carbon dated insoluble bits of organic matter contained within the sample. This test revealed one particular mound to be at least 2,200 years old. The researchers on this project proudly announced that they had found the oldest termite mounds in the world, but another group of researchers determined that the Heuweltjies mounds in South Africa are 4,000 years old.

The researchers who tested the Heuweltjies mounds determined their age by carbon dating the calcrete that developed within the hillcock. This method, although common, has been criticized for being an inaccurate method of determining a mound’s age. Carbon dating organic matter within a mound’s central vertical axis is considered a “direct” form of measurement, while carbon dating calcrete is considered to be an “indirect” form of measurement. Furthermore, some scientists believe that the Heuweltjies mounds are not actually termite mounds; instead, they are often dismissed as naturally occurring landforms that result from erosion and the gathering of aeolian sediment.

Would you be interested in visiting the Heuweltjies mounds of South Africa despite the fact that some scientists don’t believe that these mounds were created by termites?