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ON THE EDGE OF EXTINCTION - A - THE TIGER (Panthera tigris) - Printable Version

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RE: ON THE EDGE OF EXTINCTION - A - THE TIGER (Panthera tigris) - Betty - 01-07-2018

A large female tiger weighing 200-250 kg was killed.







RE: ON THE EDGE OF EXTINCTION - A - THE TIGER (Panthera tigris) - Betty - 01-07-2018

Huai Kha Khaeng Wildlife Sanctuary  


A female Indochinese tiger weighing 140kg.

https://www.posttoday.com/social/env/445551



*This image is copyright of its original author



RE: ON THE EDGE OF EXTINCTION - A - THE TIGER (Panthera tigris) - Greatearth - 01-07-2018

Rishi

I think you know a lof of the Bengal tiger in Orissa and Sundarbans.
A tiger in these area has one of the most dangerous competitor just as the brown bear, the saltwater crocodile. Is there any reliable interactions between these croc and tiger? All I know is one female tiger was killed by saltwater crocodile after 4 hours battle or something.

100 years ago, the Bengal tiger in coastal areas of Tamilnadu, Andhrapradesh, Orissa, West Bengal, Bangladesh and western Burma definitely faced with these animal since saltie habitat was also very wide spread (saltwater crocodile was once ranged Seychelles islands of Africa to western Oceania).
Someone in wildfact wrote interaction result between these two apex predators were the tigers usually dominated the saltwater crocodiles in past. I don't know this is really true and I am curious where did this person got this information. I know tiger preying on mugger crocodile in Ranthambore and other parts of India. Female tiger Machilli killed numerous 4.2~4.5 m long crocodiles by herself. However, the saltwater crocodile is no joke compared to smaller mugger crocodile. In fact, there is some belief of the biggest saltwater crocodile may living in Orissa state right now. One thing is that many media describes the saltwater crocodile as 7 to 10 meters, but this is one big wrong information. 6 meters long saltwater crocodile is the same as 220 cm tall human. This is the only species of crocodile frequently grows 5.2 meters long (male), but saltwater crocodile average length is still around 4.2~4.5 meters for both adult male (4.3~4.9 m) and female (while the maximum length of the mugger crocodile is around 4.8 m). I guess tiger could take down saltwater crocodile, but Sundarbans tiger is smaller than tigers from other parts of India and Nepal.

The Sumatran tiger, Malayan tiger, and Indochinese tiger also interacted with salties in last century before human destroyed many of wildlife. But these tigers are smaller than the Bengal tiger while it may have been depend by regions (I read that tiger in Annam and Laos was just a little bit smaller than the Bengal tiger, but tiger in Cochinchina and Mekong delta was the same size as the Sundarbens tiger from previous post). I don't know many information of the Malayan tiger, Indochinese tiger, and Sumatran tiger (their size, morphology and appearance by different locations). If anyone knows more information of these tiger subspecies from different locations. Please write more of these tiger subspecies since they are also very interesting tiger subspecies just like the Bengal tiger in Himalaya and Sunderbans.

I deleted one of my post, but critically endangered Siamese crocodile and Chinese alligator are a small Crocodilians. The Siamese crocodile was once widespread in entire Indochina besides Malayan peninsula and the Chinese alligators was widespread near Yangtze river. The South China tiger and Indochinese tiger probably easily killed and prey on these adult crocodile/alligator just like the jaguar and caiman relationship in the Pantanal and other parts of the Americas. Unfortunately, Siamese crocodile is almost extinct in wild and the South China tiger is extinct in wild.


RE: ON THE EDGE OF EXTINCTION - A - THE TIGER (Panthera tigris) - Greatearth - 01-08-2018

Familiy tree of the South China tiger rewilding program

I don't know what is going on in here, but looks like breeding has been successful. Total 14 tigers from 4 South China tiger in 2017.
And geneticists should find out how to increase gene pool without reintroducing another subspecies to ruin pure subspecies. This is helping many critical endangered animal like Asiatic cheetah, Whooping crane, Javan rhino, Sumatran rhino, California condor, and many other animals/plants.


*This image is copyright of its original author



RE: ON THE EDGE OF EXTINCTION - A - THE TIGER (Panthera tigris) - Greatearth - 01-08-2018

Subspecies and range map of tigers in mainland China

This is a photo I found. I think the South China tiger (Panthera tigris amoyensis) was referring to tiger lived in Zhejiang, Fujian, Jiangxi, Hunan, Guangdong, and Guizhou (Also part of Anhui and Jiangsu).

Does anyone have a clue which tiger lived in mainland China? Is there any old books mentioning anything like morphology, size, and other things about these tigers?
1) Northern mainland China (North of Yellow river to Beijing): Hebei, Shandong, and Shanxi
2) Central China (between Yangtze river and Yellow river): Shandong, Jiangsu, Anhui, Hubei, Henan, and Shaanxi
3) Boarder of China and Vietnam: Yunnan and Guangxi


*This image is copyright of its original author



RE: ON THE EDGE OF EXTINCTION - A - THE TIGER (Panthera tigris) - GrizzlyClaws - 01-08-2018

(01-08-2018, 11:05 AM)Greatearth Wrote: Subspecies and range map of tigers in mainland China

This is a photo I found. I think the South China tiger (Panthera tigris amoyensis) was referring to tiger lived in Zhejiang, Fujian, Jiangxi, Hunan, Guangdong, and Guizhou (Also part of Anhui and Jiangsu).

Does anyone have a clue which tiger lived in mainland China? Is there any old books mentioning about these tigers?
1) Northern mainland China (North of Yellow river to Beijing): Hebei, Shandong, and Shanxi
2) Central China (between Yangtze river and Yellow river): Shandong, Jiangsu, Anhui, Hubei, Henan, and Shaanxi
3) Boarder of China and Vietnam: Yunnan and Guangxi


*This image is copyright of its original author


The South China tiger also lived in the northern part of China, except Manchuria.


RE: ON THE EDGE OF EXTINCTION - A - THE TIGER (Panthera tigris) - Greatearth - 01-08-2018

GrizzlyClaws


Yeah, I do know that. But I think every sources are mentioning as differently. 
I think many information in internet is just mentioning as southern China to Yellow river. 

This is what Wikipedia is saying:
"The historical range of the South China tiger stretched over a vast landscape of 2,000 km (1,200 mi) from east to west and 1,500 km (930 mi) from north to south in China. From the east it ranged from Jiangxi and Zhejiang Provinces at about 120°E westward through Guizhou and Sichuan Provinces at about 100°E. The most northerly extension was in the Qinling Mountain and Yellow River area at approximately 35°N to its southern extension in Guangdong, Guangxi and Yunnan Provinces at 21°N."

And I am also asking something about them from old books, their morphology and size as well. I am sure Southern China tiger, Central China tiger, and Northern China tiger may have been different from each other.


RE: ON THE EDGE OF EXTINCTION - A - THE TIGER (Panthera tigris) - GrizzlyClaws - 01-08-2018

The historical North China tiger was probably the northern population of the Amoyen tiger, but they also could get some admixture from the Amur tigers consider the geographical proximity.

The South China tiger probably got admixture from the Indochinese tiger, and I think the Central China tiger was probably the genetically purest Amoyen tiger.


RE: ON THE EDGE OF EXTINCTION - A - THE TIGER (Panthera tigris) - Greatearth - 01-08-2018

GrizzlyClaws

I think the South China tiger probably got admixture from the Bengal tiger in western part of Yunnan. While today's South China tiger is probably closer from the Indochinese tiger.

There is one river/canyon name "Tiger Leaping Gorge" in Three Parallel Rivers of Yunnan Protected Areas. A name got it from legend that saying a tiger jumped across the river at the narrowest point.
Three Parallel Rivers of Yunnan Protected Areas is in Diqing Tibetan Autonomous Prefecture, Yunnan province. This place is very close to Myanmar and Tibet. Three great rivers of Asia, Yangtz, Mekong, and Salween rivers are flowing here. There are many new species are discovering here to Indochina through rivers. One problem is China built many dams in Tibet and decreased the water amount. Han chinese is always problems through the world (there are 52 different ethnic group in China and these people are not living well). That is one reason of why many countries in South East Asia and India have many conflicts with China.
I don't know tiger once lived far as "Tiger Leaping Gorge". If they did, then the South China tiger probably meet with the Bengal tiger. Or tiger in these areas were resident of the Bengal tiger or Indochinese tiger.


*This image is copyright of its original author

*This image is copyright of its original author



RE: ON THE EDGE OF EXTINCTION - A - THE TIGER (Panthera tigris) - GrizzlyClaws - 01-08-2018

Indeed, there were historical Bengal tigers in China's southwest part.

Even the Asiatic elephants of China's southwest part belong to the Indian subspecies, not the original Chinese subspecies which had been extinct long time ago.


RE: ON THE EDGE OF EXTINCTION - A - THE TIGER (Panthera tigris) - Rishi - 01-10-2018

(01-07-2018, 05:58 AM)Greatearth Wrote: Looks like these Bengal tigers are well adapted in steep Himalayan mountains in Bhutan. They don't look massive and robust body like Wagdoh, Madla, and other tigers from India...

...It is fair that studying ecology and morphology of the Bengal tiger from Himalayan mountains in Bhutan could understand some stuffs for the other tiger subspecies lived in steep mountain areas like the Caspian tiger and South China tiger.

That means you haven't seen them all...That problem can be solved. Skim through this thread, it's short:

Tigers of High Himalayas.

Some of them live less than 50kms away from the lowlands of Assam & Duars, exchanging genes with each other, thanks to the whole region being an unfragmented forest block. 

Buxa tigers move range to foothills of Bhutan border.

Bhutan tiger sighted in Neora Valley.

Quote:Is there any reliable interactions between these croc and tiger? All I know is one female tiger was killed by saltwater crocodile after 4 hours battle or something.

100 years ago, the Bengal tiger in coastal areas of Tamilnadu, Andhrapradesh, Orissa, West Bengal, Bangladesh and western Burma definitely faced with these animal since saltie habitat was also very wide spread (saltwater crocodile was once ranged Seychelles islands of Africa to western Oceania).
Someone in wildfact wrote interaction result between these two apex predators were the tigers usually dominated the saltwater crocodiles in past...

...I guess tiger could take down saltwater crocodile, but Sundarbans tiger is smaller than tigers from other parts of India and Nepal.

Tiger/crocodile fatalities caused by each other are very low ( Most bodies are usually found, washed downstream by the tides & dumped on the banks of wider rivers, as most bouts take place near water). The last such incident was recorded in 2011, and before that another incident two years ago in 2009.

I'm not a fan of picking a few random incidents & using them to "prove" something as law. So, here are my two cents...

Tigers dominate on the land & crocs in the water, but they do their best to avoid each other. 

From what i've inferred from reading hundreds of stories & tales on Sundarban's backdrop, most tigers are somewhat afraid of crocodiles.
Mostly because they are completely vulnerable to them every time they cross streams.Young, inexperienced individuals probably make mistakes leaving traumatic memory & scars.

Crocodiles get attacked on the land, out of spite, otherwise both leave the other alone. 

On their size/weight relative to their mainland cousins, i will make a detailed post shortly in the The Sundarban Tigers thread.


RE: ON THE EDGE OF EXTINCTION - A - THE TIGER (Panthera tigris) - peter - 01-13-2018

(12-23-2017, 10:39 PM)GrizzlyClaws Wrote: It is intriguing that the most impressive fossil records of the Amur tiger still belonged to Manchuria, and based on the report, I am assuming that the fossil tigers from the Russian Far East were somewhat comparable to the Korean tigers in term of size.

Maybe these fossil tigers were likely more linked to the historical Korean tigers than to the Manchurian tigers?

Interesting suggestion, Grizzly. I've been thinking about this one for a long time. Although a good answer is all but impossible, we could give it a try.


1 - QUOTES FROM THE SUMMARY OF THE BARYSHNIKOV ARTICLE

1a - " ... Five AMS C clades were made on the tiger bones. They ranged between 34 300 and > 40 000 years. Six AMS C dates were made on the hyena bones. They ranged between 34 510 and 48 560 years. This means that the layer in which the bones of tigers and hyenas were found was deposited in a Late Pleistocene warm phase (MIS3) ... " (pp. 01);

1b - "... A recently conducted mitochondrial analysis sorts out recent populations of Panthera tigris into six clades or subspecies (Luo et al., 2004). The reduced genetic variability within the grouping of Amur tiger, P. tigris altaica, could be a result of the postglacial colonization of the region (a) and a population bottleneck that happened not earlier than 10 000 years ago (b). The genetic similarity between the Caspian tiger, P. tigris virgata, and the Amur tiger, P. tigris altaica, suggests the Russian Far East was colonized from Central Asia (pp. 04);

1c - " ... Another analysis embracing morphological, ecological, and molecular data revealed a ... marked overlapping of characters between recent tiger populations as well as their low genetic variability (Wilting et al., 2015). As a result of this analysis, it was proposed to accept only two subspecies: Panthera tigris tigris (Linnaeus, 1858) in the continental part of Asia and Panthera tigris sondaica (Temminck, 1844) in the islands of Sumatra, Java and Bali ... " (pp. 05);

1d - " ... The lack of marked genetic differences between continental tiger populations can be explained by the late migration to northern Asia in the Holocene. Tigers presumably migrated to northern Asia on two occasions: during the Late Pleistocene warming (MIS3) and during the warm Holocene interglacial. They (tigers) most probably were not present in northern parts of Asia before approximately 18 000 years ago ... " (pp. 05).

1e - " ... The teeth of the fossil tigers ..., and the m1 in particular, are larger than those of Panthera tigris altaica. The lower carnassials of recent tigers, however, seem more advanced than those of Late Pleistocene tigers ... " (pp. 05).

1f - " ... The ... fossil ... ulnas do not exceed the size of the ulna in the recent P. tigris, whereas this bone is noticeably larger in P. spelaea and the recent P. leo ... " (pp. 03).    

1g - " ... All bones found (tibia, os calcaneous, os talus and a few fragments of metatarsal 2,3,4 and 5) are smaller than those of P. spelaea and sizewise correspond to those of the recent P. tigris ... " (pp. 03).


2 -  PRELIMINARY CONCLUSIONS

2a - The tiger bones found in the caves in the Russian Far East are 35 000 - 50 000 years old. This means that the layer in which they were found was deposited during warm Late Pleistocene warm phase.

2b -  The reduced genetic variability within the grouping of Amur tiger was a result of the postglacial colonization of the region (a) and a population bottleneck that happened not earlier than 10 000 years ago.

2c - The genetic similarity between the Caspian and the Amur tiger suggests that the Russian Far East was colonized from Central Asia.

2d - A recent analysis based on morphological, ecological and molecular data showed a marked overlapping of characters between recent tiger populations and low variability of the different local populations or subspecies. For this reason, Wilting proposed to distinguish between mainland and island tigers

2e - Tigers only migrated to northern Asia during the Late Pleistocene warming and the warm Holocene interglacial.

2f - The bones of Late Pleistocene tigers found in the Russian Far East suggest they were similar in size to recent tigers living in that region (Panthera tigris altaica). Bones and mandibles of male cave lions, Panthera spelaea, were larger.


3 - OTHER STUDIES 

Based on what was known, I wrote a summary about tiger evolution in 2014. This paragraph has a few quotes we could use.
  
3a - The first true tiger fossils, about 1,6 million years old, were found in Ci Saat and Trinil deposits in Java. They are considered remains of the Trinil tiger, Panthera tigris trinilensis (pp. 01).

3b - P. tigris trinilensis spread from Java to mainland Asia in the early Pleistocene, when the Sunda Shelf was connected to mainland Asia. This is the first wave and it is assumed P. tigris trinilensis ... replaced the more primitive Chinese tiger (pp. 01).

3c - A new tiger evolved in mainland Asia in the Middle Pleistocene. Panthera tigris acutidens, the Wahsien tiger, replaced P. tigris trinilensis (pp. 01).

3d - P. tigris acutidens reached Berengia. Unlike the cave lion P. spelaea spelaea, it wasn't able to cross this land bridge. In the south, during the last stages of the Pleistocene, P. tigris acutidens replaced P. tigris oxygnata, which had replaced P. tigris trinilensis, and evolved into P. tigris soloensis, possibly the largest tiger ever (pp. 01).

3e - About 75 000 years ago, the Toba erupted. The eruption destroyed large parts of Sumatra and had a profound impact on climate. The change in conditions resulted in many extinctions and population bottlenecks. In mainland Asia, tigers all but disappeared. They only survived in northern Indochina and southern China. This population evolved into the recent tiger P. tigris. From Indochina, they spread to northern and western China, reaching the Caspian by using the Silk Road less than 10 000 years ago (Driscoll et al., 2009). From there, they spread west and east. Just before they reached the Silk Road, tigers colonized India about 12 000 years ago (pp. 01-02)   

3f - The land bridge between mainland Asia and the Sunda Shelf existed until approximately 50 000 years ago. Mainland tigers going south and Sunda tigers going north met in Sumatra, where they mixed and evolved into P. tigris sumatrae. When the land bridge disappeared, Sumatran tigers became separated. As a result of the long separation, they, according to some, developed into a different species: Panthera sumatrae (pp. 02).


4 - BIOGRAPHICAL CHANGE IN THE TIGER, PANTHERA TIGRIS (A.C. Kitchener and A.J. Dugmore, 1999)

4a - " ... The number of tiger subspecies is a major conservation issue that is difficult to resolve owing to small fragmented extent populations and limited historical samples in museums, which compromise the rigour of both molucular and morphological taxonomic studies. Rather than considering a static taxonomic approach to geographical variation in the tiger, we consider the changing biogeographical range of the tiger through the last glacial-interglacial cycle, based on habitat associations of modern tiger specimens records, and environmental reconstructions from the last Glacial Maximum (LGM; approximately 20 000 years before present (B.P.)). We regard this cycle as representative of the numerous glacial cycles that span the evolutionary history of the tiger since its appearance in the fossil record about two million years ago, thereby giving a time-deep perspective.

The key issue is to determine the extent to which ancestral populations of the tiger were geographically isolated. If no ... isolation is likely, and gene flow between tiger populations could be maintained until modern times, than diagnostically distinct populations could not have evolved.

Our reconstructions show that only two tiger populations were likely to have experienced significant geographical isolation from the main distribution; these were to the west of Tibet (during the LGM) and on Japan (throughout the glacial cycle). In addition, the LGM is likely to have seen the partial separation of peninsular Malayan and Sunda tigers from mainland populations. From a biographical perspective it seems probable that only three contemporary populations were sufficiently separated for the evolution of distinct populations, which can be regarded as subspecies or evolutionary significant units. Therefore, most variation in modern tiger populations is probably clinal, which has importasnt implications for future conservation both in the wild and in captivity ... " (abstract).

4a - Two maps suggesting that the Russian Far East wasn't colonized by Caspian tigers spreading east about 20 000 years ago:


*This image is copyright of its original author



*This image is copyright of its original author
       

5 - TIGERS IN NORTHERN ASIA

5a - Baryshnikov wrote that the bones found in the caves in the Russian Far East in the sixties and seventies of the last century are roughly 35 000 - 50 000 years old. He also wrote that Late Pleistocene tigers, although about similar in size, had slightly larger teeth than the recent tiger living in that region, P. tigris altaica. Both were smaller than cave lion males, P. spelaea.    

5b - Based on the studies referred to above, Baryshnikov concluded that tigers only colonized northern Asia in the last stages of the Pleistocene or in the Holocene, most probably no before 18 000 years ago. This means that the tigers living in the Russian Far East 35 000 - 50 000 years ago had come from the west or east. As there is hardly any difference between Caspian and Amur tigers, most assume that the Russian far East was colonized by Caspian tigers going east. Kitchener and Dugmore (1999), however, concluded it's unlikely that Caspian tigers reached the Russian Far East before the Holocene. Based on the maps above, this region, in their opinion, had to be colonized from the south. Japan and Korea, however, can't be completely excluded from the equasion. 

5c - Different studies suggest that tigers in northern Asia (P. tigris virgata, P. tigris altaica and P. tigris amoyensis), are different from tigers in southern Asia.

   
6 - CONCLUSIONS

6a - In his article, Baryshnikov discribes 211 tiger bones of 6 individuals found in a number of caves in the Russian Far East. The bones were found in layers that were deposited 35 000 - 50 000 years ago roughly. We're talking about the Late Pleistocene, that is. The bones are not very different from the bones of recent tigers living in the Russian Far East; teeth a bit more primitive and a trifle larger, but that's about it.

The same Baryshnikov, in the same article, says northern Asia was only colonized by tigers in the last stages of the Pleistocene and, in particular, the Holocene. There were no tigers in northern Asia before 18 000 years ago, that is. But he found overwhelming proof of Pleistocene tigers living in the Russian Far East well before that mark. So what's going on here? And where did these Late Pleistocene tigers in the Russian Far East come from? 

From the west, Driscoll said. Caspian and Amur tigers are just about one and the same. Could be, but Kitchener and Dugmore argued it's very unlikely that Caspian tigers reached the Russian Far East before, say, 20 000 years ago. 

The question still is where the Late Pleistocene tigers in the Russian Far East came from. Based on the maps of Kitchener and Dugmore, China seems to be the best option. But Japan and Korea can't be completely excluded. About 20 000 years ago, Japan still had tigers. The conditions, in fact, were excellent. Japan tigers are present in all maps.

In short. What I found is unclear, if not contradictory.

6b - Based on what I read, my guess is that tigers did reach northern Asia and Japan in the middle Pleistocene during a warm phase. According to Kitchener and Dugmore, Japan was almost completely colonized about 100 000 years ago. When the ice returned, tigers in central and northern parts of Asia most probably moved to the southwest (the Caspian region) and the southeast (northern China, the Russian Far East and Japan). When the conditions improved once more, Caspian tigers moved to the east and Amur tigers (tigers from Japan, Korea, the Russian Far East and northeastern China) moved west. Must have happened more than once until 15 000 - 20 000 years ago.

6c - In the Holocene, the human population exploded. Japan tigers were perhaps the first to go. This was after Japan had become separated as a result of rising sea levels. In tigers, separation always results in a loss of size. My guess is that Japan tigers were smaller than average. Korean tigers were next. Although they survived in densely forested and elevated regions until the early decades of the 20th century, they too became isolated over time. Large individuals were shot until the end every now and then, but the isolation must have had an effect on size. The region between the Caspian and the Russian Far East had breeding tigers, but Heptner and Sludskij and V. Mazak concluded that the conditions were unfavourable. In the last three centuries, this region must have seen tigers on the move. When fire-arms were introduced, these travelers disappeared.

Manchuria and the Russian Far East offered the best chances for tigers. As the conditions in Manchuria in particular were good for a long time, it is no surprise that tigers, sizewise, reached a peak in this region. If we add that Manchuria and the Russian Far East were somewhat out of reach for both the Chinese and the Russians for quite some time (no large cities, no agriculture and a harsh climate), it is no surprise that they did quite well until the last decades of the 19th century. When Japan had occupied Korea and Manchuria, it was game over. Only after they had left, the tiger situation, thanks to Kaplanov, got some attention.

The loss of size of Amur tigers could be a result of a lack of gene exchange mainly. There are no tigers left in Japan, Korea, Manchuria and the Altai Mountains. Amur tigers are on their own, that is. If we add a population bottleneck between 1900-1950 (resulting in inbreeding), 60 000 hunters (resulting in competition and prey depletion) and habitat destruction (the Russian Far East has many natural resources, which resulted in new roads offering plenty of opportunities to poachers), it is no wonder that they struggle. Amur tigers now are protected, but views can change overnight.

6d - If I would have a say, I would recommend a new study based on literature only. The first task is to eradicate contradictions and get to a number of conclusions supported by all. Preconceived ideas should be removed and everything we have should be invested in establishing and securing a number of large reserves closed to the public for quite some time. Russia and northeastern Manchuria seem to be the best options, but central parts of China also offer opportunities. In 2011, it still had a small number of wild tigers.


7 - FUTURE

7a - During the last weeks, I found quite a bit on Amur tigers, tigers in northern parts of China and tigers in central and southeastern China. The aim is to start with Amoy tigers (southeastern China) and slowly move north. 

The Chinese tiger, Panthera tigris amoyensis, had different faces in different parts of China. Although large and robust individuals have been shot in the south, Amoy tigers were less robust than tigers in central parts of China. Tigers in northern China, as far as I know, always have been quite large. In the recent past, Manchuria and the southwestern part of the Russian Far East could have been a region where tigers from different regions have met and bred.

7b - This thread has quite a few links to interesting articles and a number of good posts about tiger evolution. Posts 740 to 790 are recommended for those interested in evolution.


RE: ON THE EDGE OF EXTINCTION - A - THE TIGER (Panthera tigris) - GrizzlyClaws - 01-13-2018

There were indeed other tiger population in the northeast part of Asia prior the colonization of the Caspian tiger.

Now the question is that the modern Amur tigers are simply the pure descendant of the Caspian tigers, or simply the hybrid descendants of the late arrived Caspian tigers and the residual population of the Wanhsien tigers? Although the majority of the Amur tigers might have the Y-DNA and mtDNA of the Caspian tigers, but autosomally, they could still be somewhat influenced by the residual Wanhsien tigers, that's why they don't look identical to the original Caspian tigers, just like the modern humans in Europe who had been autosomally affected by the Neanderthals, who don't look identical to the original humans from Africa.

BTW, those theories are still not based the empirical evidence, but rather from my armchair opinion, but I am expecting they could manage to discover something later that matches my opinion.


RE: ON THE EDGE OF EXTINCTION - A - THE TIGER (Panthera tigris) - peter - 01-14-2018

THE HISTORY OF AMUR TIGERS

A - Research

The bones described by Baryshnikov prove that the Russian Far East had tigers in the Late Pleistocene. According to Baryshnikov, these tigers were not very different from the recent tiger living in that region, P. tigris altaica. Genetic research (driscoll et al., 2009) revealed that P. tigris altaica and P. tigris virgata are just about one and the same. This means that the Russian Far East was colonized by Caspian tigers moving east. According to Kitchener and Dugmore, Caspian tigers only migrated to the Russian Far East in the Holocene. In that period, China tigers also moved to northern Asia.

So what do we have? 

B - A few preliminary conclusions

01 - The bones from the caves suggest there was not much difference between Late Pleistocene tigers and recent tigers in the RFE.
02 - We know that Amur tigers and Caspian tigers are almost identical. 
03 - Based on -01- and -02-, the conclusion is that the Late Pleistocene tigers in the Russian Far East were Caspian tigers.
04 - Kitchener and Dugmore, however, concluded that Caspian tigers only migrated to the Russian Far East in the Holocene.

Something is not right, that is. Here's a few hypotheticals. 

C - Ideas

05 - Caspian tigers in the RFE colonized the RFE in the Late Pleistocene (a) and in the Holocene (b).
06 - If -05- is correct, Kitchener and Dugmore were not.  
07 - Unless (see -06-) the tiger population in the RFE disappeared in the Late Pleistocene and the RFE was recolonized in the Holocene.
08 - If -07- is correct, the RFE had to be recolonized in the Holocene by the same tigers living in this region in the Late Pleistocene. 
09 - As -08- seems very unlikely, we have to assume that Kitchener and Dugmore were wrong for now.
10 - Unless (see -09-) northern Asia was colonized by Amur tigers moving west. 
11 - Which (see -10-) is unlikely, as the genes of Caspian tigers show more 'age' than Amur tigers.
12 - Based on 01-11, we have to assume that the RFE was colonized by Caspian tigers in the Middle Pleistocene and in the Holocene.

D - Japan, Korea and northern China 

Based on what I have, I'd say that Korean tigers were not very different, if at all, from Amur tigers. A bit smaller perhaps, but Korean tigers lived on the edge (sea on three sides) and tigers living on the edge often are smaller than tigers living in other regions. Most of Korea is quite similar to the RFE. This means that Amur tigers moving east and south might have colonized Korea in the Holocene without much problems, when Japan became isolated and Japan tigers disappeared completely.

And what about tigers in northern China moving to northern Asia in the Holocene? This is a bit of an enigma. It's likely that some individuals reached the Altai Mountains and the region east of Lake Aral, where they would have met with P. tigris virgata. Manchuria, a sea of forest in that period, would have been more suited to tigers. So suited, in fact, that it would have been a true tiger paradise. Every now and then, during a crop failure when wild boars moved north, some Manchurian tigers would have followed them but it is unlikely they settled in northern Asia for lack of opportunities. Wild boars nearly always returned to the sea of forest down south.

E - Amur tigers and Manchurian tigers

My guess is there were outspoken differences between tigers living in northern Asia (the Caspian region, the Altai Mountains, northern part of Mongolia, the RFE and Korea) and Manchurian tigers (and tigers in northern China in general). The first type was, and still is, quite long and tall but not as heavy as a tiger of similar size living in a food hotspot, whereas Manchurian tigers, also large, were true forest cats living in a region of plenty. Manchurian tigers, also facing severe cold every winter, always had more resources. For this reason, size was a good option. Manchurian tigers might have compared to tigers living in similar regions in India today; large and robust.

Amur tigers, in spite of quite a few years of protection and a significant increase in numbers, still have very large territories. The reason is a lack of large prey animals. Amur tigers need to learn how to deal with energy deficits, hills and competition. We can't exclude the occasional giant, but my guess is a large size would be a disadvantage in a region with harsh living conditions. In a way, Amur tigers, although isolated, compare to Himalayan tigers, also long, tall and large. My guess is that Himalayan tigers are larger and heavier for the simple reason they have more access to large prey animals. Plenty is not a result of coincidence in that region. In the RFE, its most certainly is.   

F - Panthera tigris acutidens

And what about the descendants of P. tigris acutidens? Could they have survived the consequences of the Toba eruption and mixed with P. tigris virgata at some stage, in this way securing their genes? My guess is they did.

I've seen many captive tigers and concluded that Amur tigers are very different. It shows in many ways. The skull is more elevated, longer and more primitive. The body is different as well. As soon as they get the chance, captive Amur tigers, and males in particular, produce a size hardly ever seen in other subspecies. All other subspecies, including Manchurian tigers, produce large and bulky individuals in exceptional conditions, but Amur tigers, even when very large, nearly always combine power with athleticism. In their winter coat, males may seem to be bulky or even fat, but in most cases it's deceptive.

Captive Amur tigers seem to be docile and social animals. Quite often, they are. When they lose their temper, however, they produce something I never saw in other big cats. More than once, I thought an enraged male would demolish his cage. I never was the only one who thought so, but I usually was the only one who stayed. It's a kind of energy difficult to describe. A century ago, in Korea, Manchuria and the RFE, Amur tigers searched for mates in winter. The sounds of fighting males during a frosty night unnerved many hunters. Some left the scene during the night, never to return. Others had to be hospitalized. 

We now know that Amur tigers hunt and sometimes fight bears of near-similar size. We take it for granted, but it's not. Bears are very powerful and agile animals that can take a lot of damage. Killing a bear is not easy and a fight is very risky for any tiger. I'm not saying that Amur tigers hunt bears on a regular basis, but research says it's close in some parts of the RFE, especially in summer and autumn. Living with bears is not easy for any big cat. Hunting them even less so, let alone engage them. Nearly all wild Amur tigers need to be experienced in this respect. It's something that sets them apart. In order to get an idea, read interviews with trainers. Bears usually are more dangerous than big cats.
          
Could the behaviour regarding bears be a result of something from the past, or are Amur tigers no different from other subspecies? One could make a case for the second option, but I thought I saw something from a period in which humans didn't really participate.


RE: ON THE EDGE OF EXTINCTION - A - THE TIGER (Panthera tigris) - GrizzlyClaws - 01-14-2018

I was also suspecting that the diversity within Amur tiger population could be the result of the admixture with other paleo tiger population.

Technically, the Manchurian tiger is a subtype of the Amur tiger that is different from other regular Amur tigers. It is possible that they got more admixture from the Wanhsien tiger than the regular Amur tiger? Since the Manchurian tiger was less cursorial and more forest adapted than the regular Amur tiger, and the Wanhsien tiger was also a pure forest type of tiger that used to disperse all over of China from north to south before the Toba eruption.

However, the Manchurian tiger right now is also functionally extinct in the wild, maybe only few individuals remain in the captivities around the world, so we can only speculate right now.