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Whale Cetaceans
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• Surfacing behavior
Many whales exhibit behaviors such as breaching and tail slapping that expose large parts of their bodies to the air.
• Lifespan
Whale lifespans vary among species and are not well characterized. Whaling left few older individuals to observe directly. R.M. Nowak of Johns Hopkins University estimated that humpback whales may live as long as 77 years. In 2007, a 19th century lance fragment was found in a bowhead whale off Alaska, suggesting the individual could be between 115 and 130 years old. Aspartic acid racemization in the whale eye, combined with a harpoon fragment, indicated an age of 211 years for another male, which, if true would make bowheads the longest-lived extant mammal species. The accuracy of this technique has been questioned because racemization did not correlate well with other dating methods.
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