Details - The ecology of hybridization in New Guinea honeyeaters (Aves)

The ecology of hybridization in New Guinea honeyeaters (Aves)

Title

The ecology of hybridization in New Guinea honeyeaters (Aves)

Related Titles

Series: American Museum novitates, no. 1937

By

Gilliard, E. Thomas (Ernest Thomas), 1912-1965

Type

Book

Material

Published material

Publication info

New York, N.Y, American Museum of Natural History, [1959]

Notes

Title from caption.

"April 22, 1959."

"Observations shedding new light on the hybridization of wattle birds and black-billed honeyeaters (Mayr and Gilliard, 1952b) are presented. Evidence is presented that the two groups are not conspecific, despite their interfertility under certain widespread conditions of habitat disturbance. New collections from the Victor Emmanuel, Hindenburg, and Mittag mountains, as well as nestlings from three widely separated regions of eastern, central, and western New Guinea, are analyzed. It is demonstrated that wattle birds are essentially forest-edge birds of the northern watershed and that the black bills are essentially pure forest birds of the central range and southern watershed. The hypothesis is advanced that, as a result of the removal of the mountain forests by man, these two morphologically very different groups were brought into hybrid contact and that zones of hybridization formed along the artificial forest edges in the midst of what had formerly been pure mountain forest. In such 'belt'-shaped areas of disturbance, in which the mechanisms of ecological isolation between the two groups of honeyeaters had been destroyed, wattle-bird genes flowed into new regions with black-bill genes to form hybrid swarms that sometimes became secondarily isolated. Two such swarms are postulated to have become stabilized and to have become taxonomically distinct from the parent species. The question of taxonomic recognition for 'races' of hybrid ancestry between valid species is studied, and the conclusion is reached that morphological criteria and not lines of descent should dictate whether such races are valid or not. The problem of the assignment of such a race to a species group is studied. It is decided to assign it to the parent it more nearly resembles. These conclusions are expressed in a revision of these two groups of hybridizing honeyeaters in which the wattle birds and the black bills are recognized as constituting two distinct species. Two races of hybrid ancestry (but nearest in composition to black bills) are recognized"--P. 24-25.