Surfer's ear, associated with cold weather and water sports, a team at the Smithsonian in Panama to suspect that ancient shoreline residents were diving for pearls in an area of cold-water up-welling.
While examining a skull from an ancient burial ground in a pre-Columbian village in Panama, Nicole Smith-Guzmán, bio-archaeologist at the Smithsonian Tropical Research Institute (STRI), was surprised to discover an example of surfers' ear: a small, bony bump in the ear canal common among surfers, kayakers and free divers in cold climates. After inspecting more skulls, she concluded that a select group of male divers -- perhaps looking for pearls and oyster shells coveted for jewelry making, may have lived along Panama's Pacific coast long ago.
No one really understands exactly how the bony growths, technically called exostoses, form. But the skin is thin in the ear canal and the accepted theory is that cold water or cold temperatures caused by wind and water make the bone react by growing extra layers, similar to the way bone spurs form on the feet and in other places where there is constant irritation or stress. Almost half of the members of a swimming club in England had surfer's ear according to a report cited in the study.
Unlike most tropical countries where seawater is warm, water temperature in the Gulf of Panama plummets between January and April when strong trade winds from the north force warm surface water out into the Pacific and colder, deep water rises to the surface to replace it. This deep, nutrient-rich water feeds tiny sea organisms, which in turn are eaten by fish and whales. The Gulf becomes an extraordinarily productive fishing ground supporting a thriving fishing industry and attracting dolphins, sharks and other top-of-the-food-chain animals.
The team also ruled out fungal or bacterial ear infections common in the tropics that sometimes cause bone deformations: most of the skulls affected were from males, and infections should occur in both male and females at about the same rate. From the evidence they have so far, it looks like mostly males were involved in whatever activity caused surfer's ear in Panama. In another study, archaeologists in the Canary Islands found roughly equal numbers of cases of surfer's ear in ancient male and female skulls, suggesting that aquatic activities there were not restricted to one gender.
Surfer's ear is an intriguing subject that archaeologists, anthropologists and medical doctors have explored for more than a century. Although the exact causes of this phenomenon is still debated, these bony growths offer important clues into the cultural activities, gendered division of labor and environmental conditions in the past.