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ON THE EDGE OF EXTINCTION - A - THE TIGER (Panthera tigris)
ON THE EDGE OF EXTINCTION - A - THE TIGER (Panthera tigris)
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ON THE EDGE OF EXTINCTION - A - THE TIGER (Panthera tigris)
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I request all members to kindly post any information or links related to genetics of tigers of all subspecies, their status, their scope for future and scope for conservation and other topics.
Sunderbans,
 *This image is copyright of its original author Western TAL,  *This image is copyright of its original author http://jultika.oulu.fi/files/isbn9789526215662.pdf 
there is variation within every group, here's few that i can break down.
Group 1 Satpura Pench (Mp) Pench (Mh) Kanha Group 2 Tadoba Melghat Nagzira Bor Group 3 Panna Group 4 Sariska Group 5 Ranthambore Group 6 Assam Group 7 Nagarhole Bandipur Wayanad Group 8 South Terai Group 9 North Terai Group 10 Indian side Sunderbans Group 11 Bengladesh side Sunderbans to be fair, its easy to tell the tigers apart from every part of India with the most obvious group being the Ranthambore. they are easy to distinguish from every other group. thick stripes, very tall and generally brindle coats. 
COPTERS
Interesting observations. Can you describe every group (ground colour, stripes and pattern, prey animals, habits regarding humans and size)? If too complicated, you can try to describe the differences between the groups. Recent (genetic) research suggests there could have been 2 waves in the past: one directed to mainland India and a later wave moving west just south of the Himalayas. Tigers in central and southern India seem to be somewhat darker. Stripes also darker and a bit more dense. In the 19th century, hunters thought so-called 'Bengal tigers' were longer, whereas those in central India were generally more robust and somewhat bigger. Pocock and a few others underlined this observation in that they concluded that skulls from central parts of India, although generally a bit shorter, often were relatively wider and more robust. Man-eaters were more common in central India as well. In general, hunters thought that they were more aggressive regarding humans. Reliable info on size, however, suggests that tigers shot in northern and northwestern India and Nepal in the 20th century were taller, longer and heavier (averages). They apparently also quickly overtook central Indian tigers in the departments of aggression and man-eating. The second wave is of interest in particular. The reason is Caspian tigers. Although research suggests that Caspian tigers are closely related to Amur tigers, a wave from northwestern India into Pakistan, Afghanistan and further west can't be excluded. When they can survive in Bhutan, tigers in the recent past (10 000 - 15 000 years ago) should have been able to cross ranges of up to 15 000 feet, possibly even even a bit more. Based on what I have, I concluded there could have been different subpopulations in the Caspian region. Those in the southwestern part could have been different from those in the northeastern part. ALL Anyone interested in the issues discussed is invited to participate in the debate. It is about the answers to 4 questions: 1 - Are tigers in mainland India different from those just south of the Himalayas and, if so, in what respects? 2 - Are there differences between regions in mainland India, or are tigers in India more or less similar? 3 - Would tigers living in the southern part of the Himalayas have been able to cross this range some, say, 10 000 years ago? Tell us why you got to your answer. 4 - Do Amur tigers and Himalayan tigers compare or not? If yes, in which respects? And what about the differences?
Western terai arc landscape,
 *This image is copyright of its original author
@peter I have been doing a lot of research on this since a few days. My answers to your questions are,
1. I suppose you mean by south of himalayas, the tigers of Terai Arc Landscape. If so there is a study conducted on these tigers that show they have one unique haplotype in higher frequency that was absent in rest of India. Here is the link, https://www.researchgate.net/publication...L_of_India By some facial phenotypic characters, i suppose Corbett and Ramnagar tigers are unique. Just like in humans, mongoloids have unique facial traits that is easily recognizable to them, corbett and ramganga tigers seem to be having those unique facial traits. If observed closely we can trace them. Chitwan tigers were proven to be different population than the rest of Terai Arc landscape. Rajaji tigers too is a smaller sized tigers similar in size to corbett tigers but do not exhibit the facial traits of corbett tigers. Rest of terai like dudhwa, katarniaghat and nepal terai except chitwan seem to be one group. Coming to Northeast tigers (these too are to the south of himalayas hence discussing) these tigers have unique genetics as i have already posted in assam tigers thread. Even you too are aware of this. These tigers are completely different than those of rest of India. I suppose their stockiness and compact muscled bodies are the variations when compared to other groups. Also their compact bodiness and stockiness may be due to mixture of Indochinese genes in them. They share the connecting gene pool with south east asian tiger population hence the differences. http://wildfact.com/forum/topic-genetics...1#pid42451 2. There seem to be differences in mainland India and regions with border sharing with other countries. North Indian tigers have pale coat while those to central and soouthern have relatively darker coats. That may be due to colder climates, but it may also be due to genetic admixture with other tiger subspecies in north of India. Tigers from himalayas and kashmir shared historical connection with caspian and siberian habitats. So, there may be considerable number of hybrids from history, they must have successfully cross bred and must have passed their genes the result pale coloration may be due to this. 3. Tigers must have crossed the link between India and south east some 12000 years ago as per a study. Through south east or china they must have come to India through south of himalayas.  *This image is copyright of its original author 4.They compare in some respects like paler stripes, light winter coat in case of corbett tigers and colder area region tigers, larger bodies etc. Not that south indian tigers these days are relatively smaller but generally speaking. But they seem to have the equal muscular bodies as the rest of India tigers. So, they may be having the admixture of siberian or caspian genes with those genes admixed over time to form a completely different and unique genotype in border areas of himalayas than towards the south. That may be the difference between himalayan tigers and amur tigers as per my observation.
Subgroups among Indo Chinese tigers,
 *This image is copyright of its original author
Notion of breeding wild and captive tigers due to lack of genetic diversity in the wild,
 *This image is copyright of its original author  *This image is copyright of its original author  *This image is copyright of its original author  *This image is copyright of its original author Https://whitetigertruths.wordpress.com/f...-research/  *This image is copyright of its original author Source:
Source: https://www.google.co.in/amp/s/phys.org/...scores.amp n
Another article regarding satpura landscape https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3568842/ Good news about central Indian tigers,  *This image is copyright of its original author
Source: http://journals.plos.org/plosgenetics/ar...en.1000585
Compared to other subspecies, they have high variation but still not  *This image is copyright of its original author enough for long term survival 
One more article highlighting the role of genetic diversity
http://news.stanford.edu/news/2014/april...41814.html  *This image is copyright of its original author
ANSWERS TO THE FIRST TWO QUESTIONS IN POST 1,222
1 - Introduction Yesterday, Parvez asked me if I had read a recent article about the genetics of tigers in the Terai Arc Landscape. I hadn't, but adviced him to contact Tigerluver. He did. Today, Tigerluver posted the link to the article in the thread 'The Terai Tiger': http://wildfact.com/forum/attachment.php?aid=915 The title of the article, accepted on October 18, 2010, is 'Genetically distinct population of Bengal tiger (Panthera tigris tigris) in Terai Arc Landscape (TAL) of India'. The article, an 'original investigation', was written by R. Sharma, H. Stuckas, R. Bhaskar, I. Khan, S.P. Goyal, S.P. and R. Tiedemann and published in 'Mammalian Biology', 76 (2011): pp. 484-490. The project was supported by the DAAD (German Academic Exchange Service) and the University of Potsdam. Markward Fischer of the 'Senckenberg Naturhistorische Sammlungen' (Dresden) assisted in the figures department. 2 - Abstract The authors analyzed mtDNA polymorphisms in 91 scats and 12 tissue samples of tigers from 3 different populations in northern India; the Terai Arc Landscape (TAL), the Buxa Tiger Reserve (BTR) and northeastern India. Now for the results: 2a - They found a specific haplotype in TAL and BTR. As this haplotype was absent elsewhere, the conclusion is that tigers in these regions (TAL and BTR) are genetically different from those in other regions in India. 2b - Within the TAL region, they found some evidence for genetic isolation of tigers west of the Ganges river, like the western part of the Rajaji National Park (RNP). The isolation, most probably, wasn't a result of the river, but of human-induced changes and degradation of the Motichur-Chilla Corridor. 2c - Apart from the western part of the Rajaji National Park, the tiger population in the TAL, a region with a length of 900 km. and a width of 50-60 km., was genetically cohesive. 2d - Tigers of Royal Chitwan National Park in Nepal, in spite of its proximity to the TAL-region, are genetically different from tigers in the TAL-region. 2e - Tigers in the northeastern part of India are different from TAL and BTR tigers. They're also different from Chitwan tigers and tigers in others regions of India. 3 - Haplotypes in 7 Indian regions The article has a map with haplotype frequencies in 7 Indian regions (northeastern India, Buxa (BTR), Chitwan, northern India (TAL), western India, central India and southern India. Of these 7 regions, 4 have haplotypes not seen in other regions. They are northern India (4 unique haplotypes - TIG 8, TIG 11, TIG 12 and TIG 13), northeastern India (2 unique haplotypes - TIG 14 and TIG 15), Chitwan (1 unique haplotype - TIG 4) and southern India (1 unique haplotype - TIG3). Haplotype TIG5 is most often shared (northeastern India, Chitwan, western India, central India and Southern India). Haplotypewise, northeastern India has connections with Chitwan (low), western India (high), central India (moderately) and southern India (high). There is no connection between northeastern India and Bux (BTR) and northern India (TAL). 4 - The answers to the first two questions in post 1,222 4a - Are tigers in mainland India different from those just south of the Himalayas? The answer is yes regarding tigers in the TAL-region and Buxa (BTR) and no regarding Chitwan. Tigers in the TAL-region and Buxa (BTR) do not share a single haplotype with with tigers in western, central, and southern India. Chitwan tigers, on the other hand, share haplotype TIG6 with central India and TIG5 with western, central and southern India. Chitwan tigers also have a unique haplotype (TIG4). Same for tigers in southern India (haplotype TIG3). 4b - Are there differences between regions in mainland India? The answer is no. Tigers in western, central and southern India share haplotype TIG5 (75% and over in all regions). Central Indian tigers share haplotype TIG6 with Chitwan tigers and western India tigers share haplotype TIG10 with tigers in northeastern India. Tigers in southern India are a bit different in that they have a unique haplotype (TIG3). 5 - Conclusions 5a - Tigers living just south of the Himalayas are genetically different from tigers in others regions in India. It is, however, remarkable that tigers in northern India (TAL) and Buxa (BTR) share haplotype TIG7 (well over 85% and only seen in these 2 regions), whereas Chitwan, located between the TAl-region and Buxa, show no trace of this haplotype. Not at all. 5b - Tigers in northeastern India are genetically also are very different from tigers in other regions, but they share some haplotypes (TIG2, TIG5 and TIG10) with tigers in western, central and southern India. This is not true for tigers in the TAL-region and Buxa. 5c - Chitwan tigers are an enigma. As it isn't a result of geographic isolation (Chitwan is connected to the TAL-region), the question is why Chitwan tigers are not related to tigers in Buxa and the Terai Arc Landscape.
@peter I can guess the reason for chitwan tiger enigma. These tigers must have been distinct population from past with it's genes spreading through corridors. Chitwan must be having something unique in it's habitat or landscape absent elsewhere in terai. These tigers must be having superior skin quality among terai tigers. The surrounding corridor tigers carrying these unique genes must have been targeted for poaching and must have been eliminated. Chitwan being a protected place must have guarded it's tigers. Thus those unique genes are present only in chitwan.
Northeast has probably the highest genetic diversity. That's good news as I once doubted their genetic diversity. And possibly the biggest Bengal tigers are now in safer side with high genetic diversity.
 *This image is copyright of its original author
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