Short-beaked & Long-beaked Common Dolphin [status update]

Gestart door Hans Verdaat, januari 13, 2023, 15:28:45 PM

Vorige topic - Volgende topic

Hans Verdaat

Scientific view on Short-beaked & Long-beaked Common Dolphin has changed in recent years. See:

Source: Encyclopedia of Marine Mammals -Third Edition, 2017-

Delphinus delphis

"Previous editions of this book recognized two globally distributed species of common dolphins: the short-beaked common dolphin Delphinus delphis and the long-beaked common dolphin D. capensis as proposed by Heyning and Perrin (1994). However, according to the Committee on Taxonomy [Society for Marine Mammalogy] (2016), "... evidence that D. capensis thus considered is a polyphyletic taxon has been accumulating for some time. The long-beaked condition is apparently a convergent character state induced by regional ecology. In some regions, long-beaked common dolphins are genetically more closely related to short-beaked common dolphins than to long-beaked common dolphins in other regions (e.g., see Natoli et al., 2006). Cunha et al. (2015) summarized the relevant data and analyses, along with additional molecular data and analysis, and recommended that D. capensis not be further used as proposed by Heyning and Perrin (1994)." That recommendation is followed here. Further, "Cunha et al. (2015) noted that because the sympatric/parapatric long-beaked and short-beaked common dolphins off California in the Eastern North Pacific (ENP) appear not to interbreed, perhaps the ENP long-beaked common dolphins might be recognized as a separate species D. bairdii (Dall, 1873). However, the genetic analysis for the ENP (Rosel et al., 1994) did not include samples from the contiguous regions to the south in the eastern tropical and eastern south Pacific where common dolphins occur." (Committee on Taxonomy, 2016). Pending a more complete global review and revision of the common dolphins, the long-beaked ENP form is here considered a subspecies D. d. bairdii. Three recognized subspecies are shown in Fig 1."