The Birds of Northern Melanesia Speciation, Ecology, and Biogeography

by Mayr, Ernst; Diamond, Jared

• ISBN13: 9780195141702
• ISBN10: 0195141709
• Format: Hardcover
• Copyright: 2001-12-06
• Publisher: Oxford University Press

Summary

Speciation is the process by which co-existing daughter species evolve from one ancestral species - e.g., humans, chimpanzees, and gorillas arising from a common ancestor around 5,000,000 years ago. However, many questions about speciation remain controversial. The Birds of Northern Melanesia provides by far the most comprehensive study yet available of a rich fauna, composed of the 195 breeding land and fresh-water bird species of the Bismarck and Solomon Archipelagoes east of New Guinea. This avifauna offers decisive advantages for understanding speciation, and includes famous examples of geographic variation discussed in textbooks of evolutionary biology. The book results from 30 years of collaboration between the evolutionary biologist Ernst Mayr and the ecologist Jared Diamond. It shows how Northern Melanesian bird distributions provide snapshots of all stages in speciation, from the earliest (widely distributed species without geographic variation) to the last (closely related, reproductively isolated species occurring sympatrically and segregating ecologically). The presentation emphasizes the wide diversity of speciation outcomes, steering a middle course between one-model-fits-all simplification and ungeneralizable species accounts. Questions illuminated include why some species are much more prone to speciate than others, why some water barriers are much more effective at promoting speciation than others, and whether hypothesized taxon cycles, faunal dominance, and legacies of Pleistocene land bridges are real. These years of study have resulted in a huge database, complete with distributions of all 195 species on 76 islands, together with their taxonomy, colonization routes, ecological attributes, abundance, and overwater dispersal. Color plates depict 88 species and allospecies, many of which have never been seen before. For students of speciation, Northern Melanesian birds now constitute a model system against which other biotas can be compared. For population biologists interested in other problems besides speciation, this rich database can now be mined for insights.

Author Biography

Ernst Mayr, born in 1904, is the Alexander Agassiz Professor of Zoology, Emeritus, Museum of Comparative Zoology, Harvard University. He is one of the principal architects of the "neo-Darwinian synthesis", which has been the dominant perspective in 20th century evolutionary biology. His numerous well-known books include Systematics and the Origin of Species, and Animal Species and Evolution. Beginning in 1928, his expeditions to New Guinea and the Solomon Islands form a core of this work Jared Diamond, born in 1937, is a Professor of Physiology at UCLA. He is the author of the best-selling and award-winning books The Third Chimpanzee, Guns, Germs, and Steel, and Why Is Sex Fun?, gaining him one Pulitzer Prize, two British Science Book Prizes, and the National Medal of Science. He has achieved high distinction in three different fields: membrane physiology, evolutionary biology, and environmental history. His knowledge of Northern Melanesian birds rests on his 19 expeditions, beginning in 1964, to New Guinea, Northern Melanesia, and adjacent islands

Table of Contents

Introduction	xv
Part I. Northern Melanesia's Physical and Biological Environment
Geology and Geological History	3	(7)
Plate tectonic history
Volcanism and rocks
Land bridges
Summary
Climate	10	(3)
Habitats and Vegetation	13	(3)
Habitats
Taxonomic composition of the vegetation
Summary
Terrestrial Vertebrates Other Than Birds	16	(11)
Mammals
Amphibia
Reptiles
Comparison of vertebrate classes
Summary
Part II. Human History and Impacts
Human History	27	(6)
Modern peoples and languages
Prehistory before European exploration
European exploration and modern history
European impacts relevant to bird distributions
Summary
Ornithological Exploration of Northern Melanesia	33	(3)
Exterminations of Bird Populations	36	(11)
What bird species may now be extinct in the Bismarcks or Solomons?
What bird species were reported by the first European explorers?
Bird fossils
Susceptibility of Northern Melanesian birds to known mechanisms of extermination
Summary
Part III. The Northern Melanesian Avifauna
Family Composition	47	(6)
Disproportions between the Northern Melanesian and New Guinean source avifaunas
Disproportions based on a revised classification
Summary
Determinants of Island Species Number	53	(9)
Species/area relation
Effect of isolation
Montane species
Supersaturation
Summary
Level of Endemism, Habitat Preference, and Abundance of Each Species	62	(4)
Level of endemism
Habitat preference
Abundance
Summary
Overwater Dispersal Ability of Each Species	66	(12)
Indicators of dispersal
Formulation of dispersal categories in the Bismarcks and Solomons
Comparison of the types of evidence
Comparison of the Bismarcks and Solomons
Evolution of dispersal ability
Biological correlates of dispersal abilities
Summary
Distributional Ecology	78	(15)
Number of islands occupied by each species
Species incidences
Differences between the Bismarcks and Solomons in species distributions
Summary
Part IV. Colonization Routes
Proximate Origins of Northern Melanesian Populations	93	(14)
Endemic subspecies and nonendemic populations
Endemic allospecies
Endemic full species and genera
Summary
Upstream Colonization and Faunal Dominance	107	(5)
Exchanges Between the New Hebrides and Northern Melanesia
Exchanges Between the Bismarcks and Solomons
Exchanges Between Northern Melanesia and the New Guinea region
Asymmetry ratios
Summary
Ultimate Origins of Northern Melanesian Populations	112	(7)
Asian immigrants
Old Australian taxa
Other taxa
Total numbers of traceable species
Summary
Part V. Taxonomic Analysis: Differences Among Species
The Problem of Speciation	119	(7)
What are species?
Speciation
Taxonomic terms
Summary
Stages of Geographic Speciation Among the Birds of Northern Melanesia	126	(3)
Absence of Geographic Variations	129	(8)
Factors predisposing to geographic variation, or to its absence
Factors predisposing to lack of geographic variation
Classification of geographically nonvariable species by level of endemism
Summary
Geographic Variation: Subspecies	137	(8)
The frequency of geographic variation
The variable degree of geographic variation
Effects of vagility and abundance on geographic variation
Interpretation of the effects of vagility and abundance
(Lack of) relation between geographic variability and degree of endemism
The great speciators
Geographic variability of montance species
Summary
Geographic Variation: Megasubspecies	145	(8)
Examples illustrating the range of geographic variation at the subspecies level
Numbers of megasubspecies
Summary
Geographic Variation: Allospecies	153	(10)
Allospeciation in Northern Melanesia
Snapshots of colonization
Discussion
Summary
Completed Speciation	163	(16)
Examples
Data on all cases of completed speciation
Single or multiple achievements of sympatry?
Concordance between taxonomic closeness and geographic overlap
Older and younger invaders
Mechanisms of allopatric speciation
Modes of ecological segregation
Niche differences between older and younger invaders
Does ecological segregation evolve in allopatry or sympatry?
Summary
Appendix: Remaining cases of completed speciation
Hybridization	179	(3)
Endemic Species and Genera	182	(11)
Geographic distributions of the endemic full species
Vagility and abundance of endemic full species
Distribution between the Solomons and Bismarks
How did many endemics become so locally distributed?
Habitat preference
Geographic variation
Summary
Part VI. Geographic Analysis: Differences Among Islands
Endemism Index	193	(9)
Calculation of an endemism index
Interpretation of the endemism index
Volcanically defaunated islands
Land-bridge islands
Summary
Pairwise Differentiation Index	202	(7)
Examples of the pairwise differentiation index
Geographic barriers in Northern Melanesia
Dependence of the index on island areas and distance
Summary
Pairwise Nonsharing Indices: Differences in Island Species Compositions	209	(7)
Causes of pairwise differences in island species compositions
Definitions of two indices
Comparisons of the three pairwise indices
Locations of major barriers
Dependence of the nonsharing indices on island distance and areas
Summary
The Establishment of Geographic Isolates	216	(2)
Interarchipelagal Barriers	218	(9)
Barrier between Northeast New Guinea and Northern Melanesia
Barriers to the east of Northern Melanesia
Barrier between the Bismarcks and Solomons
Definition of ornithogeographic regions
Summary
Barriers Within the Bismarcks	227	(13)
Barrier between New Britain and New Ireland
The New Ireland group
The St. Mattihias group
The Northwest Bismarcks
The smaller Bismarck islands
Summary
Barriers Within the Solomons	240	(16)
The Bukida Group
The New Georgia group
The barrier between the Bukida and New Georgia group
Malaita
San Cristobal
Rennell
The smaller Solomon islands
Summary
Speciation on Fragmented Solomon Islands	256	(9)
Five consequences of island fission/fusion cycles
Speciation on Greater Bukida
New Georgia Group
Bismarck Pleistocene Islands
Summary
Differential Extinction and Species Occurrences on Fragmented Pleistocene Islands	265	(10)
Non-water-crossing species on fragments of Greater Bukida
Greater New Britain and New Ireland
Summary
Part VII. Synthesis, Conclusions, and Prospects
Conclusions about Speciation	275	(13)
The biological species concept
The whole picture of speciation assembled from snapshots
Establishment of primary and secondary isolates
Peripheral isolates
Summary
Species Differences, Taxon Cycles, and the Evolution of Dispersal	288	(12)
The taxon cycle for Melanesian ants
Habitat shifts during colonization by Northern Melanesian birds
Four evolutionary stages among Northern Melanesian birds
The montance avifauna
Evolutionary changes in dispersal ability
Summary
Promising Directions for Future Research	300	(11)
Priorities for gathering new data
Improved analyses of area and distance effects
The time scale of speciation
Distributions with complex histories
Comparisons and generalization
Summary
Maps	311	(132)
Appendices
Appendix 1. Systematic List: Breeding Land and Freshwater Native Birds of Northern Melanesia	363	(39)
Appendix 2. Nonbreeding Visitors to Northern Melanesia	402	(4)
Appendix 3. Introduced Bird Species in Northern Melanesia	406	(2)
Appendix 4. Chronologies of Ornithological Exploration	408	(6)
Appendix 5. Attributes of Each Bird Species	414	(8)
Appendix 6. Evidence of Overwater Dispersal Ability of Each Species and Allospecies in the Bismarcks and Solomons	422	(9)
Appendix 7. Distributions and Origins of Northern Melanesian Bird Populations	431	(12)
References	443	(22)
Index	465