Page "Mariana Mallard" Paragraph 3

After Salvadori, most taxonomists, such as Dean Amadon and Ernst Mayr, considered it a subspecies of the Mallard.

Yoshimaro Yamashina examined those specimens in Japanese museums in 1948, and decided that the Mariana Mallard was an example of hybrid speciation, and was descended from the Mallard and the Pacific Black Duck's Palau subspecies ( Anas superciliosa pelewensis ).

However, no molecular genetic evidence is available to support this hypothesis.

Some scientists, such as Jean Delacour, have considered the Mariana Mallard a simple hybrid, so it was absent from Delacour's four-volume monograph on the ducks and from the IUCN Red List.

If Yamashina's hypothesis is correct, the Mariana Mallard would have presumably evolved into near species status in only about ten thousand years.