Evidence of the elusive ‘Type D’ orca has been intermittently collected over the years; tales from fishermen, tourist photos, and a mass stranding incident in New Zealand in 1955. DNA taken from the stranding was analyzed in 2013, and showed that the Type D orca is genetically distinct from the other three known types of orca. They have been so rarely sighted, that the recent spotting of them by NOAA is very special indeed. The researchers were able to obtain video footage, sound recordings and DNA samples from the orcas, which may shed light on their social structure, whether their calls are distinct from other orcas, and if they are genetically different enough to justify a future reevaluation of the current system of classifying orcas by types, instead of subspecies, or species.
Source: Science Alert
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