Quote:
This is a subadult Javanese Peafowl Pavo javanensis not to be confused with the extinct Pahang (Malaysian) Peafowl Pavo muticus muticus/ ( Pavo muticus malacensi). This bird is from Bali. I suspect that there are three different subspecies of Javanese peafowl. This one is native to the south west. There is another native to the north west and still another on the east coast of Java. The species became extinct on Bali during the Dutch Hegemony of the region.
Hi Clinton,
I don't have any certainty what nomenclature the birds of Northern Thailand will have- they appear to be somewhat intermediate between imperator and annamensis. They may well represent the locus at which spicifer annamensis and imperator meet. Some might argue that that is evidence of there being no reason to split annamensis from imperator. Things are not so simple as that. We must examine the history of the region and the molecular makeup of these populations and study their behavioral ecology before making any determination, though [URL='http://en.wikipedia.org/wiki/Phenotype']phenotype and more importantly genotype are helpful in putting the systematic puzzle back together. Plumage is not always a reliable factor on its own. A combination of genotype, biogeography , behavioral ecology , voice and phenotype in that order are necessary when looking to generate a supportable cladistic model dealing with the higher systematics of land fowl.
And yes for the detractors: this missive is verbiose- comprised of far too many technical terms and hyperlinks but for future students of behavioral ecology and zoology it's vitally important that they learn this now before going to college. Clifton and Franky are older than their years but neither are in college just yet. If this annoys you just stop reading.
We have an analogous situation with races of Kalij pheasants and Silver pheasants but that have proven, despite their obvious similarities in plumage, to form discrete units of evolutionary novelty. The Lineated Kalij looks like an Annamese Silver Pheasant but both have closer relatives that do not resemble them so closely in plumage. The Lineated Kalij is closely related to theBlack Breasted Kalij . The Annamese Silver Pheasant is related to the Swinhoe's Fiery Wing . Both of these respective branches are rooted in the Crested Fireback Pheasant . It is closely related to the common ancestor of both lineages. The gradation appears to be related to elevation, ambient humidity and so on. Natural selection paints the picture .
I should stress that the systematics of these birds is often only weakly resolved because of their rapid diversification at a specific moment in evolutionary history when somewhere between 70,000 and 50,000 years ago, most of South East Asia's forests were destroyed consequent of the Mount Toba volcanic eruption. That event resulted in the emergence of the Indian Peafowl as a distinct species derived from a green peafowl ancestor. Not incidentally, the green peafowl ancestor of cristatus was relatively only recently derived itself, indeed, imperator came to exist as a distinct entity from the more primitive green peafowl (spicifer/annamensis)of Miocene days only during the Pleistocene. During Pleistocene and subsequent to Mount Toba, forest ecosystems that peafowl inhabited in Southern Asia (as opposed to South East Asia) were radically altered. The landscape in India was covered in up to twenty feet of volcanic ash. While the forests of South East Asia were largely destroyed, the ash cloud traveled westward not toward the east. Consequently, desert was not the first intact ecosystem to emerge as it were in India post Toba event. Again, the natural catastrophe generated by Mount Toba had an enormous impact on the respective evolutionary histories different peafowl species. This is why Indian Peafowl are so divergent from Green Peafowl. This is probably why cristatus thrives in semi-desert environments and even in very cold regions as a domestic companion animal.
Concurrently, Green Peafowl (and Lophura Pheasant) populations in South East Asia became incredibly fragmented and isolated from one another in the very few most sheltered regions where the effects of the supervolcano were not as devastating or even non-existent. These regions were almost invariably deep within ancient mountain ranges, such as those of the Arakan Yomas, Aranachal Pradesh , Tennasirim Mountains , Eastern Pahang Mountains ,AnnamiteMountain Range and Cardamom Mountain Range . These were probably primary refugia regions where Peafowl populations held on through the Toba event -isolated through the next tens of thousands of years. Each of these respective populations represents its own evolutionary novelty. Each race has a unique evolutionary history. They are genetically distinct from one another. Genetic distinction between some forms is even greater than that between some forms and the Indian Peafowl.
Eventually, these regional forms of Peafowl would radiate into recovering habitats and the first habitat to regenerate was that of the deciduous open forest tropical grassland mosaic. This habitat is very similar to that which was regenerating in Southern Asia (Indian subcontinent, Sri Lanka, Assam) at the same time. Of course India's deciduous forests were recovering from a much more severe situation. Their makeup is not identical with that of South East Asia by a long shot. The populations of green peafowl survivors that radiated out into the newly regenerating habitat adapted to this open deciduous forest, tropical grassland mosaic habitat, gaining new ground exponentially as this habitat raced to cover all that was previously covered by densely forested habitat destroyed by the Mount Toba eruption and subsequent volcanic winter. The open park like environment was now the dominant ecotype. Deciduous Forest, Tropical Grassland Mosaic had replaced subtropical rainforests of some regions and the broad leaf evergreen forests of other regions/altitudes that had previously dominated this landscape for millions of years.
Races of imperator inhabit deciduous tropical grassland and dry deciduous forest habitats.
Strangely, spicifer is less related to cristatus than imperator. This seems counter-intuitive given that Burma is adjacent to India.
An aside here, imperator and cristatus are Pleistocene (epoch from 2,588,000 to 11,700 years ago) aged taxa.
The antiqus javanensis clade is late Oligocene aged (~ 20) million years ago).
The spicifer annamensis clade are mid to late Miocene aged (~10 million year ago).
The spicifer annamensis clade are derived of the antiqus javanensis clade. The imperator cristatus clade are derived from spicifer annamensis .
The Indian Peafowl and the Indo Chinese Peafowl are closely allied, even though their ranges are at opposites sides of Asia because the ancestor of imperator previously had a very large range before Mount Toba erupted. That ancestor of imperator and cristatus was analogous with the Kalij pheasant which also has an east west division. Due to different habitat preferences consequent of altitude, the Kalij range is not perfectly in line with cristatus/imperator but I think the point is made. And let me make it clear, the White Crested/Nepal Kalij is a distinct species from the Lineated/Crawfurd's species. The Indian Peafowl and the Indo-Chinese Peafowl are distinct species that just so happen to evidently be each others closest relatives. The ancestors of spicifer peafowl were inhabiting broadleaf evergreen forest (open boreal), moist deciduous forest at moderate elevations. The ancestors of the cristatus/imperator lineage were inhabiting dry deciduous forest ( tropical savannah) in lower elevations. During the Pleistocene, when the proto- imperator lineage split from spicifer/annamensis, ocean levels were ~ 300' lower than they are today. With tropical savannah (pre-Toba) habitat extending in a more or less continuous expanse from India to Sumatra, the ancestors of imperator and cristatus probably had the largest range of all the existing Pavo peafowl.
What are now alluvial fans beneath shallow seas created by the major drain offs of the Ganges , Irrawaddy , Mekong and Guangxi were not so substantial as they have become since the Holocene ~ 12,000 years ago when global warming melted the world's Pleistocene Ice Sheets creating major river systems that had not existed in massive volumes before then. It was the melting of the ice sheets during the Holocene that filled the ocean to its current level.
Before Mount Toba event some 70,000 years ago, the common ancestor of imperator and cristatus had a range that extended from Eastern India, to Guangxi Tonkin Bay region. That habitat was a tropical savannah deciduous forest habitat. The ancestors of the more primitive peafowls like antiqus, spicifer and annamensis had a collective range spanning from the Annamite Mountain Range through to the eastern Himalayan Foothills to the Arakan Yomas Mountain Range. Their habitat was broadleaf evergreen forest (open boreal)forest. After the Toba event, habitats of both ecotypes were completely destroyed. This is when populations of the cristatus/imperator lineages probably began to evolve into completely distinct entities. Though clearly the Tonkin races of the Guangxi/ Hainan are clearly still very similar to the common ancestor of cristatus/imperator, which is why they look like hybrids between the two species.
When lowland south east Asia became covered in dry deciduous forest/ tropical savannah, in habitat that was previously before the Toba event, broadleaf evergreen/ open boreal forest, imperator populations flourished. There would be no more genetic exchange with their Southern Asian cousins in India. Meanwhile those primitive broadleaf evergreen forest adapted forms were obliged to ascend into higher elevations migrating away from seasonal cloud layer. Populations already isolated became even more so. That is why they are such distinctive genetic entities. The open boreal forest adapted forms of Green Peafowl are not as adaptive as the imperator and that form is not as adaptive as the cristatus.
recap:
1. During the Mount Toba event here were different Pavo species inhabiting respective regions/ecotypes.
a.antiqus: tropical pine forest
superspecies:
b.spicifer/annamensis/bokorensis: broadleaf evergreen/ open boreal forest
c.cristatus/imperator lowland deciduous forest, tropical grassland
d. javanensis - not sure yet-molecular data -no confidence on that just yet but may be allied with antiqus
2.Supervolcano goes off ~ 70, 000 years ago destroys 80+% of Asia's forests and causes volcanic winter.
a.Refugia habitats sheltered in mountain valleys, harboured populations of green peafowl for many thousands of years.
3.Eventually, a climatic equilibrium returns and tropical grassland/deciduous forest spring up, replacing pre-existing broadleaf/open boreal forest habitats inhabited by spicifer/annamensis/bokorensis clade.
Corridors -vegetated in open deciduous forest enabled populations of the imperator's ancestor to radiate throughout lowland Indo-China.
Those very corridors along which lowland peafowl migrated out from, those survivors of Mount Toba event- the tropical savannah corridors closed behind them in many regions. Huge rivers changed course behind them as they radiated out. Tropical forests returned to much of what had been open park-like forest only a few thousand or even hundred years before. These rainforests and ever growing drainage basins of major rivers would subsequently act as barriers between new peafowl populations.
Forested lowland regions that had been entirely devastated by the Toba event in India and South East Asia recovered into park like open forest of the deciduous nature. This habitat became the preferred habitat of the two most successful and highly evolved peafowl species (cristatus/imperator) . Other peafowl like Cardamom Mountain range bokorensis and Bolaven Plateau annamensis remained in their refugia forest habitats, those of broadleaf evergreen and open boreal nature -at substantially higher elevations than one might expect peafowl to exist in. This was also true of arakansis and antiqus, antiqus ( of Shangrilah ) inhabiting tropical pine forest biome, a very different habitat than typical green peafowl inhabit. Nevertheless, this is a habitat that was prevalent during Oligocene times and is probably what fossil European species of peafowl inhabited during the Miocene[/url]
This is a subadult Javanese Peafowl Pavo javanensis not to be confused with the extinct Pahang (Malaysian) Peafowl Pavo muticus muticus/ ( Pavo muticus malacensi). This bird is from Bali. I suspect that there are three different subspecies of Javanese peafowl. This one is native to the south west. There is another native to the north west and still another on the east coast of Java. The species became extinct on Bali during the Dutch Hegemony of the region.
Hi Clinton,
I don't have any certainty what nomenclature the birds of Northern Thailand will have- they appear to be somewhat intermediate between imperator and annamensis. They may well represent the locus at which spicifer annamensis and imperator meet. Some might argue that that is evidence of there being no reason to split annamensis from imperator. Things are not so simple as that. We must examine the history of the region and the molecular makeup of these populations and study their behavioral ecology before making any determination, though [URL='http://en.wikipedia.org/wiki/Phenotype']phenotype and more importantly genotype are helpful in putting the systematic puzzle back together. Plumage is not always a reliable factor on its own. A combination of genotype, biogeography , behavioral ecology , voice and phenotype in that order are necessary when looking to generate a supportable cladistic model dealing with the higher systematics of land fowl.
And yes for the detractors: this missive is verbiose- comprised of far too many technical terms and hyperlinks but for future students of behavioral ecology and zoology it's vitally important that they learn this now before going to college. Clifton and Franky are older than their years but neither are in college just yet. If this annoys you just stop reading.
We have an analogous situation with races of Kalij pheasants and Silver pheasants but that have proven, despite their obvious similarities in plumage, to form discrete units of evolutionary novelty. The Lineated Kalij looks like an Annamese Silver Pheasant but both have closer relatives that do not resemble them so closely in plumage. The Lineated Kalij is closely related to theBlack Breasted Kalij . The Annamese Silver Pheasant is related to the Swinhoe's Fiery Wing . Both of these respective branches are rooted in the Crested Fireback Pheasant . It is closely related to the common ancestor of both lineages. The gradation appears to be related to elevation, ambient humidity and so on. Natural selection paints the picture .
I should stress that the systematics of these birds is often only weakly resolved because of their rapid diversification at a specific moment in evolutionary history when somewhere between 70,000 and 50,000 years ago, most of South East Asia's forests were destroyed consequent of the Mount Toba volcanic eruption. That event resulted in the emergence of the Indian Peafowl as a distinct species derived from a green peafowl ancestor. Not incidentally, the green peafowl ancestor of cristatus was relatively only recently derived itself, indeed, imperator came to exist as a distinct entity from the more primitive green peafowl (spicifer/annamensis)of Miocene days only during the Pleistocene. During Pleistocene and subsequent to Mount Toba, forest ecosystems that peafowl inhabited in Southern Asia (as opposed to South East Asia) were radically altered. The landscape in India was covered in up to twenty feet of volcanic ash. While the forests of South East Asia were largely destroyed, the ash cloud traveled westward not toward the east. Consequently, desert was not the first intact ecosystem to emerge as it were in India post Toba event. Again, the natural catastrophe generated by Mount Toba had an enormous impact on the respective evolutionary histories different peafowl species. This is why Indian Peafowl are so divergent from Green Peafowl. This is probably why cristatus thrives in semi-desert environments and even in very cold regions as a domestic companion animal.
Concurrently, Green Peafowl (and Lophura Pheasant) populations in South East Asia became incredibly fragmented and isolated from one another in the very few most sheltered regions where the effects of the supervolcano were not as devastating or even non-existent. These regions were almost invariably deep within ancient mountain ranges, such as those of the Arakan Yomas, Aranachal Pradesh , Tennasirim Mountains , Eastern Pahang Mountains ,AnnamiteMountain Range and Cardamom Mountain Range . These were probably primary refugia regions where Peafowl populations held on through the Toba event -isolated through the next tens of thousands of years. Each of these respective populations represents its own evolutionary novelty. Each race has a unique evolutionary history. They are genetically distinct from one another. Genetic distinction between some forms is even greater than that between some forms and the Indian Peafowl.
Eventually, these regional forms of Peafowl would radiate into recovering habitats and the first habitat to regenerate was that of the deciduous open forest tropical grassland mosaic. This habitat is very similar to that which was regenerating in Southern Asia (Indian subcontinent, Sri Lanka, Assam) at the same time. Of course India's deciduous forests were recovering from a much more severe situation. Their makeup is not identical with that of South East Asia by a long shot. The populations of green peafowl survivors that radiated out into the newly regenerating habitat adapted to this open deciduous forest, tropical grassland mosaic habitat, gaining new ground exponentially as this habitat raced to cover all that was previously covered by densely forested habitat destroyed by the Mount Toba eruption and subsequent volcanic winter. The open park like environment was now the dominant ecotype. Deciduous Forest, Tropical Grassland Mosaic had replaced subtropical rainforests of some regions and the broad leaf evergreen forests of other regions/altitudes that had previously dominated this landscape for millions of years.
Races of imperator inhabit deciduous tropical grassland and dry deciduous forest habitats.
Strangely, spicifer is less related to cristatus than imperator. This seems counter-intuitive given that Burma is adjacent to India.
An aside here, imperator and cristatus are Pleistocene (epoch from 2,588,000 to 11,700 years ago) aged taxa.
The antiqus javanensis clade is late Oligocene aged (~ 20) million years ago).
The spicifer annamensis clade are mid to late Miocene aged (~10 million year ago).
The spicifer annamensis clade are derived of the antiqus javanensis clade. The imperator cristatus clade are derived from spicifer annamensis .
The Indian Peafowl and the Indo Chinese Peafowl are closely allied, even though their ranges are at opposites sides of Asia because the ancestor of imperator previously had a very large range before Mount Toba erupted. That ancestor of imperator and cristatus was analogous with the Kalij pheasant which also has an east west division. Due to different habitat preferences consequent of altitude, the Kalij range is not perfectly in line with cristatus/imperator but I think the point is made. And let me make it clear, the White Crested/Nepal Kalij is a distinct species from the Lineated/Crawfurd's species. The Indian Peafowl and the Indo-Chinese Peafowl are distinct species that just so happen to evidently be each others closest relatives. The ancestors of spicifer peafowl were inhabiting broadleaf evergreen forest (open boreal), moist deciduous forest at moderate elevations. The ancestors of the cristatus/imperator lineage were inhabiting dry deciduous forest ( tropical savannah) in lower elevations. During the Pleistocene, when the proto- imperator lineage split from spicifer/annamensis, ocean levels were ~ 300' lower than they are today. With tropical savannah (pre-Toba) habitat extending in a more or less continuous expanse from India to Sumatra, the ancestors of imperator and cristatus probably had the largest range of all the existing Pavo peafowl.
What are now alluvial fans beneath shallow seas created by the major drain offs of the Ganges , Irrawaddy , Mekong and Guangxi were not so substantial as they have become since the Holocene ~ 12,000 years ago when global warming melted the world's Pleistocene Ice Sheets creating major river systems that had not existed in massive volumes before then. It was the melting of the ice sheets during the Holocene that filled the ocean to its current level.
Before Mount Toba event some 70,000 years ago, the common ancestor of imperator and cristatus had a range that extended from Eastern India, to Guangxi Tonkin Bay region. That habitat was a tropical savannah deciduous forest habitat. The ancestors of the more primitive peafowls like antiqus, spicifer and annamensis had a collective range spanning from the Annamite Mountain Range through to the eastern Himalayan Foothills to the Arakan Yomas Mountain Range. Their habitat was broadleaf evergreen forest (open boreal)forest. After the Toba event, habitats of both ecotypes were completely destroyed. This is when populations of the cristatus/imperator lineages probably began to evolve into completely distinct entities. Though clearly the Tonkin races of the Guangxi/ Hainan are clearly still very similar to the common ancestor of cristatus/imperator, which is why they look like hybrids between the two species.
When lowland south east Asia became covered in dry deciduous forest/ tropical savannah, in habitat that was previously before the Toba event, broadleaf evergreen/ open boreal forest, imperator populations flourished. There would be no more genetic exchange with their Southern Asian cousins in India. Meanwhile those primitive broadleaf evergreen forest adapted forms were obliged to ascend into higher elevations migrating away from seasonal cloud layer. Populations already isolated became even more so. That is why they are such distinctive genetic entities. The open boreal forest adapted forms of Green Peafowl are not as adaptive as the imperator and that form is not as adaptive as the cristatus.
recap:
1. During the Mount Toba event here were different Pavo species inhabiting respective regions/ecotypes.
a.antiqus: tropical pine forest
superspecies:
b.spicifer/annamensis/bokorensis: broadleaf evergreen/ open boreal forest
c.cristatus/imperator lowland deciduous forest, tropical grassland
d. javanensis - not sure yet-molecular data -no confidence on that just yet but may be allied with antiqus
2.Supervolcano goes off ~ 70, 000 years ago destroys 80+% of Asia's forests and causes volcanic winter.
a.Refugia habitats sheltered in mountain valleys, harboured populations of green peafowl for many thousands of years.
3.Eventually, a climatic equilibrium returns and tropical grassland/deciduous forest spring up, replacing pre-existing broadleaf/open boreal forest habitats inhabited by spicifer/annamensis/bokorensis clade.
Corridors -vegetated in open deciduous forest enabled populations of the imperator's ancestor to radiate throughout lowland Indo-China.
Those very corridors along which lowland peafowl migrated out from, those survivors of Mount Toba event- the tropical savannah corridors closed behind them in many regions. Huge rivers changed course behind them as they radiated out. Tropical forests returned to much of what had been open park-like forest only a few thousand or even hundred years before. These rainforests and ever growing drainage basins of major rivers would subsequently act as barriers between new peafowl populations.
Forested lowland regions that had been entirely devastated by the Toba event in India and South East Asia recovered into park like open forest of the deciduous nature. This habitat became the preferred habitat of the two most successful and highly evolved peafowl species (cristatus/imperator) . Other peafowl like Cardamom Mountain range bokorensis and Bolaven Plateau annamensis remained in their refugia forest habitats, those of broadleaf evergreen and open boreal nature -at substantially higher elevations than one might expect peafowl to exist in. This was also true of arakansis and antiqus, antiqus ( of Shangrilah ) inhabiting tropical pine forest biome, a very different habitat than typical green peafowl inhabit. Nevertheless, this is a habitat that was prevalent during Oligocene times and is probably what fossil European species of peafowl inhabited during the Miocene[/url]
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