From studying specimen skins at various natural history museums around the world, Wolfgang and I have discovered that there is some phenotypic diversity amongst the Malaysian forms. The birds from the northern western coast of the Pahang have traits unique to them - as do birds from the south western interior respectively. Likewise, birds of the north along the Pahang are always going have some of the Tennasirim genetics somewhere in their gene pool.
Edited by Resolution - 11/17/11 at 7:24pm
The issue has always been an insufficient description of races of green peafowl and also in the general incapacity to distinguish the different forms- we never have had this problems with populations of Kalij or birds of paradise because they are small enough that the natural history collectors of the day were able to collect them in sufficient numbers leading to further investigation. Peafowl are so large there is no room to store their skins- and so only a few are really maintained anywhere- and then there is the issue of where does one begin to look phenotypically - what constitutes a genuine topographic region of the bird that matters- the generalizations of descriptions reveal how little ornithological reference material has made its way into avicultural circles- it was considered antiquated and too terminological by the wealthy collectors of Delacour's day- and hence the proper terminology and vernacular of ornithological description has largely vanished in literature on galliformes.
Consequently, if I say to so and so twenty year pro breeder of peacocks- the median coverts of this specimen reveals that it is not imperator. They will not only draw a blank they will generally also make up their minds that their ignorance of this term somehow justifies negative judgement against their powers of discernment - and this will generally lead to a real resentment of the messenger (me) and that useful ornithological descriptor- of a specific topographic region- used by ornithologists since the 18th century AD will be marginalized if acknowledged at all. It's been a slow and steady stream of information and this generation of peafowl enthusiasts will most certainly come about. The problem is then going to be educating the older generations who resist these descriptions- with the lofty experts laying out a healthy dose of condensation (sic)
minimizing the description and even dissembling the significance of defining geographic races of the peafowl- - Really- this generation just has to gain the greater comprehension and keep their minds open to continue learning- and very importantly, help to educate conservationists and enthusiasts alike.
What has happened with founder stock is that birds trapped in a specific country are named by the subspecies (based on Delacour's preliminary description) as if wild species only exist within political boundaries. Bangkok is or rather was the centre of distribution of most of the gene pool of all the captive green peafowl as this was one of the major hubs of the bird trade in Delacour's day. Southwestern Cambodia is very close to Bangkok. Birds from the Cardamom/Elephant Mountain Range are certainly more brilliant in colouration than the Siamese form of lowland eastern Thailand- and obviously Tennasirim peafowl of southernmost Thailand. Because of their dazzle they were demed worth more and consequently exported to Europe where they ended up being segregated into the Malaysian breeding gene pool. I don't think this is much of an issue because they are close relatives anyway- they clade together genetically -in the very preliminary genetic work of the very few individuals we've been able to assess. Moreover, both forms are exceedingly endangered with the Malaysian form extinct in the wild and the Cardamom and Elephant Mountain Range races very nearly so.
Then there is the biogeography of the region-
This is the issue of the mountain range that runs vertically from just north of the Cardamom/Elephant Mountain Range and just runs straight north through Laos and into the foothills of southern Yunnan. This mountain range runs parallel with that of the Isthmus Kra, which terminates in the Pahang of Malaysia. This mountain range of which I am ignorant terminates in the Bokor region - the Cardamom Mountain Range.
Franky, can you please help educate me on the name of this mountain range? Can you visualise it?
These major mountain ranges contain the last vestiges of the primeval broadleaf evergreen forest that once dominated all of South East Asia. This was the original habitat of the ancestral green peafowl. During the Toba Event the only surviving populations of this ancestral green peafowl- and there may well have already been very distinct races- even species in the case of antiqus and javanensis for example, survived only in the most sheltered reaches of these ranges. They were then left isolated from other peafowl populations for tens of thousands of years.
In time, as an ecological equilibrium was met again- the broadleaf evergreen forest ascended in elevation- and with it populations of what we have referred to as theannamensis morphotypes.The moderate elevations of these mountains is where this annamensis type peafowl thrived.
The dead old forest of the lowlands from sea level up to about three thousand feet- was ravaged by fire and flood and overgrown with swamp forest giving way in succession to bamboo forest. These are habitats peafowl cannot survive in. Finally, a few tens of thousands of years later, the water table dropped and yet another habitat emerged in the lowlands- the dry deciduous tropical grassland biome and this was habitated by a new form of green peafowl- one that is derived of survivors of all the other remnants of ancestral green peafowl scattered sporadically in fragments of the original forest habitat destroyed in the great cataclysm. The imperator is at its foundation a composite of annamensis, spicifer and yunnanensis.. I tend to think that imperator is largely derived of yunnanensis but that historically, tens of thousands of years ago- migrations of yunnanesis streaming down into present day lowland Thailand, intergraded to some extent with fragmented populations of spicifer in the west and with annamensis in the north and east.
Gaining a real comprehension of these mountain ranges is absolutely integral -and in combination with major river systems- we gain a better understanding of where and why the different forms of peafowl diverged- but we must also keep in mind that even the major rivers have themselves diverged over the course of the peafowl's evolutionary history. Tributaries have come and gone and let's not forget that most of lowland Thailand was an inland freshwater sea for the entire Holocene. It was at this point in time that the Lewis's Black Silver Pheasant and the Cardamom Dragonbird were left isolated on what was then an island- the island that is the Cardamom/Elephant Mountain Range- this is where they were isolated for tens of thousands of years before that inland sea gave way to tropical grassland and deciduous forest in some regions and coastal marsh and swamp jungle in others. There is exceedingly damp rain forest to the north and west -taking up a great deal of the mountain range and this of course also serves as a barrier between peafowl populations.
Our mistake is to assign a subspecific designation to a population of peafowl based on appearance alone- we must also take into consideration the biogeographical history of that region and visualise wildlife corridors, wildlife refugia zones and ecological barriers between populations.
This is a map of Cambodia. The Cardamom/Elephant Mountain Ranges are to the bottom left of the map. This region was an island -a refugia habitat for more than 70,000 years.
During the Toba Event, mountain ranges running north to south tended to sheltered portions of southeast Asia's forest biomes. India and Sumatra bore the brunt of Toba's super volcanic cataclysm. The lower elevations and hill forests of South East Asia were largely destroyed, save for those pockets of refugia sheltered within these north south mountain ranges.
During the end of the Pleistocene, dramatic global warming melted the earth's massive ice sheets, flooding the oceans- raising sea level ~ three hundred feet. During the height of the warming period, melting ice sheets drained into the lowlands of South East Asia, drowning land bridges between Malaysia and Indonesia. They also flooded the lower elevations of what is now Thailand. Note the major river systems and mountain ranges of Thailand. During the end of the Pleistocene, these river basins were so wide that only mountain ranges stood above the water. The habitat that existed in these mountain ranges was a broadleaf evergreen forest. The annamensis peafowl can be described as an elevational form. Their preferred habitat is broadleaf forest. As the water table dropped the lowlands become dominated in swamp forest. That habitat was eventually replaced by bamboo forest as the water table continued to drop. Eventually, tropical grassland and open deciduous forest came to be the dominant ecosystem. This was only ~ 10,000 years ago. The imperator peafowl is a very recent form in comparison with annamensis and spicifer . It has radiated out into an ecosystem that was previously uninhabitable.
The imperator species is in my opinion, largely native to regions only west of the Mekong and east of the Tennasirim Hills. The siamensis form may have evolved in the Central Plain of Thailand. In my opinion, there was a largely extinct eastern imperator subspecies, tonkinensis native to Black and Red River Valleys down to the Gulf of Tonkin. There was a peafowl species native to the island of Hainan that appears (based upon its metatarsal spurs and broadness of its skull) apparently of the annamensis. This species only became extinct in the 19th century and its genetics may be infused in some captive green peafowl forms.
Anyway, please help me learn about this more or less vertical mountain range that splits South East Asia in half, that runs parallel with the Annamite Range to the East and with the Isthmus of Kra to the West. What is the name of this mountain range?
Where do Fritz's northern Thailand peafowl come from? What can we learn about them in the context of the biogeographical history of the region in question?