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Could Moby Dick Do It?

sperm whale
sperm whale

By MarEx 2016-04-07 20:10:44

The idea that a sperm whale can use its massive head as a battering ram to sink ships has been hotly debated at least since Moby Dick was published in 1851.

University of Queensland researcher Dr Olga Panagiotopoulou, part of an international team researching the theory, says scientific evidence about the phenomenon remains scarce. 

However, her research indicates that a sperm whale’s head could be used as a battering ram, and the animal could probably live to tell the tale.

Male sperm whales can be 60 feet long, and their foreheads make up one-third of their length and a quarter of their body mass. “The forehead of the sperm whale is one of the strangest structures in the animal kingdom,” said Panagiotopoulou, an expert in the anatomy, bone biology and mechanics of large animals, including elephants and non-human primates.

“Internally, the whale’s forehead is composed of two large oil-filled sacs stacked on top of each other, known as the spermaceti organ and the junk sacs.

Schematic representation of sperm whale head structure. Image courtesy of Ali Nabavizadeh and PeerJ.

“The oil in the upper spermaceti organ was the main target of the whaling industry in the early 19th century.”

Panagiotopoulou said male sperm whale heads were much larger than those of the females. Such differences between the sexes are commonly found in species in which males fight to compete for females.

A 19th century whaler originally proposed the controversial hypothesis that the sperm whale’s head could be used as a battering ram. After a large male rammed and sank his ship in the Pacific in 1820, whaler Owen Chase described the whale’s head as admirably designed for this mode of attack.

The theory was instrumental in inspiring Herman Melville’s novel Moby Dick, but until our research, its mechanical feasibility had never been addressed. The scientific community received the ramming hypothesis with reluctance.

“This was mainly because the front part of the sperm whale head houses sensitive anatomical structures that are essential for sonar communication between whales, and they would be in harm’s way in a ramming event. Also not many people had actually observed sperm whales ramming.”

The researchers were intrigued and fascinated then to receive a report from a pilot and conservation researcher who documented seeing sperm whales ramming while she was flying over the Gulf of California.

One of Panagiotopoulou’s co-researchers, Professor David Carrier from the University of Utah, said there was no explanation of how the sperm whale head could function as a weapon capable of sinking ships that are four to five times the mass of the whale. So, the interdisciplinary research team from Australia, the U.K., the U.S. and Japan used structural engineering principles and computer models to test how the sperm whale’s head might withstand ramming impacts.

Panagiotopoulou said the research showed that whale ramming events potentially could cause fatal fractures, but that the connective tissue partitions within the junk of the sperm whale forehead may function as a shock absorber. Although the unique structure of the junk certainly serves multiple functions, our results are consistent with the hypothesis that the structure also evolved to function as a massive battering ram during male-male competition, she said.
 
“Male sperm whales may not fight frequently, but we know that aggressive ramming behaviour is a common characteristic in bottle nosed whales, killer whales, narwhales, pilot whales and the group of mammals from which whales are derived- the even-toed ungulates, such as goats.”

That idea that the whales bash with the junk is supported by observations that sperm whale foreheads usually have scars on the exterior of the junk, the study said.

The research is published in the biological and medical sciences journal PeerJ.