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Edge of Extinction
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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02 - EVOLUTION (continuation)
TIGER DISTRIBUTION IN THE LAST GLACIAL MAXIMUM (models 1 and 2)  *This image is copyright of its original author  *This image is copyright of its original author Both maps (based on a number of fundamental assumptions) predict tigers in Japan and Palawan (as well as Borneo). They also explain which subgroups would have been isolated, but they do not offer an explanation as to why tigers would have survived on some islands and not others. Late's take Japan. A quite predatory and aggressive brown bear subspecies (Ursus arctos lasiotus) survives to this day, but tigers apparently disappeared a long time ago. Humans seem unlikely, as they would also have targeted the more dangerous brown bears. There has to be another reason. Anyhow. Let's move to Caspian tigers. It is generally assumed tigers followed the silk route when they spread, which means they walked north of the Gobi and the Himalayas. Not likely according to those who produced both maps:  *This image is copyright of its original author Both maps and the conclusions drawn were partly confirmed by recent research, but there also are contradictions. I noticed the remark on tigers west and east of the Caspian in particular. Morphological information and rumours about the size and character of Caspian tigers in different sources all point towards different local types east, west, north-east and south of the Caspian. Could be true, as both maps above also indicate some subgroups might have been isolated for a considerable period of time. There is very little information on tigers in most regions. Brandt (1856), quoting from Roman sources, wrote Caspian tigers were a bit smaller and wilder than tigers east of the Indus River, but the information we have from Iran (south-western part of the Elburz Mountain Range in the north-west and Mazanderan in the east) says some male Caspian tigers were hardly, if at all, smaller than Indian tigers (total length). They have shorter skulls, but the sample is small and it could be Caspian tigers, living at relatively high altitude, adapted in developing a shorter and more inflated maxillary bone. Still unclear to me, but I noticed a remarkable difference between both sexes. a) Syr-Darja, adult female (1950):  *This image is copyright of its original author b) Berlin Zoo (roundabout 1900). Both well marked and smaller than an average Indian tiger:  *This image is copyright of its original author c) Probably South-Russia, adult male:  *This image is copyright of its original author d) Iran, adult male:  *This image is copyright of its original author e) Northern Iran, adult male:  *This image is copyright of its original author
Thanks for the maps peter, I was going to put it here, but you do it first.
1. About Kitchener & Dugmore (1999): This team created two good prediction maps about who could be the climate of Asia about 20,000 years ago. They manage to predict that tigers do lived in the Sunda shelf and that its stronghold was the south east of Asia. From the two maps, that one of the HTP model is the most accurate as it predicted all the modern tiger populations and match with the accounts of tiger reports compiled by Mazák, and also show that Europe was a very suitable place for tigers (records from medieval times suggest that some tigers do reached the eastern part of the continent) but human influence prevented the tiger to enter the area. Using the HTP model, they predicted that tigers lived in a more or less continue population from the Amur region to the Sunda shelf, about 20,000 years ago. The model also proposed that the some areas around the Caspian sea and Central Asia were suitable for tigers, along with the fact that it suggest that the way for the colonization of this area was trough the north of India. The problem with this model from 1999 (copy-paste by Kitchener in his chapter of 2010, with Yamaguchi) is that recent genetic analysis show that Caspian tigers are EQUAL to the Amur population, while there is no direct genetic relation with those from India. Other problem is that this model focused in the time about 20,000 years ago, however Driscoll et al. (2009) states that the first tigers began its colonization of the west just about 10,000 years ago, which is 10,000 later than the predicted map, and probably the climate presented by Kitchener was no longer accurate at that time. In this case, the maps of Kitchener & Dugmore (1999) serve us to see that the habitat of the East and Southeast of Asia was very suitable for tiger populations, while the dry areas like India, about 20,000 years ago, were not suitable for tigers and was probably used by lions, which according with the classic theory, invaded India about 40,000 years ago. 2. Japan “tigers”: It is interesting that both maps predicted that Japan was a very suitable place for tigers in the late Pleistocene, but like peter say, it is a mystery why tigers get extinct and bears and wolves no. However, there is a big problem with this long-know “fact”: the “tigers” in Japan were, apparently, not tigers! According with the tables of Kitchener (1999), the tigers of Japan were classified as Panthera palaeosinensis, which in the old days it was classified as a primitive tiger species. However, new research shows that this great cat was closer to leopards and lions than to the tiger. Latter Kitchener & Yamaguchi (2010) classified all the cats from the late Pleistocene in Japan as “Felis youngi”, which was another great cat that showed affinities of both lions and tigers. If this is true, it will suggest that in fact, there were no tigers per se in Japan, but another primitive great cat that lived no longer than the late Pleistocene and don’t survived the Holocene. In this case, that will cut off the old assumption that tigers actually lived in Japan. 3. Tiger variations: Like I mentioned before, the Indian tigers have a great intraspecific variations, from the giant specimens from Kaziranga, the heavy Nepalese and Central India tigers, the long but lite specimens from the Western Ghats in southern India and the small “island”-sized animals from the Sundarbans. I believe that probably do existed some intraspecific variations between the populations of Amur-Central Asia-Caspian tigers. The pictures above show some small specimens and other huge ones. However, the problem is that we don’t know the age and sex of these animals, so it is impossible to state if this are in fact clinal and/or geographical variations or simple young animals compared with full grow specimens. What I believe is that Caspian tigers were no smaller than Bengal or Amur tigers, but as very few skulls are available and even less measurements are recorded, we don’t have conclusive evidence, apart from these pictures. Personally, I will not trust to much in the descriptions of the old explorers, as they observations are sometimes incomplete or based in a few, often second hand, observations.
Thanks for the addition, Guate. The part on Japan was interesting in particular. Maybe you could tell us a bit more about Panthera palaeosinensis and other frontrunners of Panthera tigris?
I decided to add a bit more on tiger evolution. The pages below are scans of a thesis of K. Lovely (Harvard, 2009). Not up to date anymore as a result of recent publications, but interesting nevertheless. A large part is directed at captive big cats and breeding programs in the USA, but the introduction on evolution (of both lions and tigers) isn't bad. 02 - EVOLUTION (continuation)  *This image is copyright of its original author  *This image is copyright of its original author  *This image is copyright of its original author The ideas regarding a common ancestor and a cline were confirmed a bit later, but Pocock's 'working hypothesis' regarding (eight) tiger subspecies in his 1929-paper has been rejected (see post 06). The idea on Panthera tigris corbetti (northern parts of Indochina) and Panthera tigris jacksioni (southern part of Indo-China) hasn't been accepted. Maybe Guate is able to get to a one-page graphic with a timeline, climatic conditions and the most recent insights regarding tiger evolution and subspecies? (04-18-2014, 03:46 AM)'peter' Wrote: Thanks for the addition, Guate. The part on Japan was interesting in particular. Maybe you could tell us a bit more about Panthera palaeosinensis and other frontrunners of Panthera tigris? I have the full document about the study of Panthera palaeosinensis. I will try to put it page by page, but if you want, I can post only the important pages. The point is that J. Mazák found that this was not a tiger, but a different species closer to the lions and leopards. Interestingly, other great cat in the same area, which is Panthera youngi, have similar affinities, just that in its case, it is closer to the lions and tigers. It seems that there were more than one big cat in the East Asia Pleistocene, but at the end, only the tiger (Panthera tigris) with its larger size and great adaptability survived, even over the large saber-tooth cats like Homotherium sp., that lived in the area at the same time. About the graphic, I will do it, but I will not include climate conditions, at least not in a deep form, because there is not much information on the subject. What it surely include will be the timeline, the evolution and all the subspecies, with images of the bones, when I have it. I will include also personal draws and if its posible, some basic morphological parameters. BORNEO [img]http://i.imgur.com/PjocStN.jpg" class="lozad max-img-size" alt="" title=""> *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 is fascinating and taking in count that there is no doubt that tigers know how to live even in dry habitats (like the Caspian region and Rajastan in India), there is practically no problem to say that tigers DO existed in Borneo. Sadly, there is no mention of the fossils itselves, but in the case of those of Palawan, we can see that the metapodials are about the same size than those from a female Bengal tigress, which means that the particular specimens found in Palawan were of that size. Obviously there is no more fossils, so we can't say if there were larger and/or smaller specimens, or even if those bones were from males or females, nor even if they were fully grow or just cubs. About the Borneo tigers, the reports say that it was of the size of a Sumatran specimen, but with a brownish coat and faint stripes.
03 - CHINA
For now, it is assumed that the only tigers who survived the Toba-eruption about 75.000-100.000 years ago were living in northern Indochina or southern China. From there, they later spread again. Here's a map of China today:  *This image is copyright of its original author This is a map of China in 1758. It shows China was populated by 5 local types (subspecies): virgata (north-west); altaica (north-east); tigris (south-west); amoyensis (central and south China) and corbetti (south). I would add styani in central and northern China, as the information I have (skull and body dimensions) point towards a clear distinction between north-central China (styani) and south-east China (amoyensis). Styani apparently was a larger animal. This is the map with subspecies (1758):  *This image is copyright of its original author Tigers in north and central China were to first to disappear. Those in south-east China were last seen somewhere in the seventies or eighties of the last century. Panthera tigris amoyensis apparently survived in captivity. This could have been one of the last in Europe (adult female in the Berlin Zoo, 1972):  *This image is copyright of its original author This one, an adult male, survived in a facility in Fujian (2003):  *This image is copyright of its original author Half a century earlier, Panthera tigris amoyensis was common in many parts of south-east China. H. Caldwell, an American missionary with a passion for hunting, wrote a book about his experiences. Here is a photograph of a tiger shot in south-east China in the last century (well before World War II):  *This image is copyright of its original author Caldwell's book was called 'Blue Tiger'. He saw 'blue' tigers on more than one occasion. Although his descriptions were clear as water, many had doubts about the colour. I don't know where this photograph was taken, but one has to assume it was China. A recent photograph. And what do we see?  *This image is copyright of its original author
Great data peter. About the distintion between "amoyensis" and "styani", I will bet for a simple cline rater than a distinct subspecies. However we most take in count that when Luo et al. (2004) studied the DNA of China tigers, they found a full lineage was practicaly undistinguishable from the "average" Indochina tiger, while the other lineage had its own haplotypes. Could this suggest that the specimens that you state as "styani" (based in Pocock, 1929, I guess) are the "new" South China tigers while those from the southern China and North Indochina (amoyensis-corbetti) are the original stream of tigers?
Other question to all of us, could the "blue" color of some tigers of that area, been a last remanent of some specimens of Wanhsien tiger that inhabitated the north of China up to the Beringia region? Definetly, the South China tiger is one of the most mysterious subspecies, ranging in size from a small Sunda tiger up to an average sized Bengal-Amur tiger. On the skull issue, I found this interesting quote: “The South China tiger is believed to have a more archaic skull, whose ratio of the length and width is relatively larger than other tiger subspecies. Its body is slim with a slender waist. It is distinguishable from other tiger subspecies by its narrower face, longer nose, more intense orange color, short fur, longer legs, and shorter & broader stripes which are spaced far apart compared with those of Bengal and Siberian tigers.” Source: http://english.savechinastigers.org/node/31 Obviously, I searched in my database and this is what I found: Subspecies Ratio GSL-ZW Sample P. t. amoyensis 1.47 6 P. t. corbetti 1.46 3 P. t. sondaica 1.43 13 P. t. altaica 1.44 13 P. t. tigris 1.41 18 Incredibly as it is, it seems that this is correct, as the largest ratio came from the South China tigers (1.47). This means that the South China tigers had a narrow skulls in comparison with the other “modern” subspecies. The second narrower group is that of Indochinese tigers, but with such a small sample (3) it is too early to achieve any final conclusion. It seems that the first tigers had narrow skulls, a trait that probably presented also the Wanhsien tiger and is now show in P. t. amoyensis (styani?). The second tiger group in evolve is that of Indochina, with also narrow skulls. The later mainland groups have much wider skulls with P. t. tigris presenting the smallest ratio. Sunda tigers seems that had changed very much trough they evolution. The Ngandong tiger had a ratio of 1.62, very narrow for any modern tiger, but latter Javanese forms seems to had increased they skull wide and carnassials’ size, but also developed smaller sagital crest and narrow occipital areas. It is obvious that Sunda tigers had different masticator systems in comparison with mainland populations. (04-22-2014, 07:18 AM)'peter' Wrote: Caldwell's book was called 'Blue Tiger'. He saw 'blue' tigers on more than one occasion. Although his descriptions were clear as water, many had doubts about the colour. I don't know where this photograph was taken, but one has to assume it was China. A recent photograph. And what do we see?This is just a photoshoped image from a normal colored tiger, nothing more. The intention of its creator, I think, was to show how a "blue" tiger would look in the past. 
I think "Styani" was just the nothern population of "Amoyensis", maybe they received some gene flow from the Amur tigers due the geographic reason.
That is also a good explanation. After all, is impossible to avoid the fact that in modern times, Amur tigers and China tigers probably crossed they pats in the south of the Manchurian region.
In fact, there is some discrepancy between Mazák (1983) and Nowell & Jackson (1996) about the classification of the specimens in Central China. This map from Kitchener & Dugmore (1999) show the problem.  *This image is copyright of its original author Interesting, don't you think? Some time ago, I worked in a series of measurements on live tigers in order to get an accurate idea of the proportions of the body of a tiger. In this case, I was trying to found how much of the length of a tiger correspond to the head. My final results produced a ratio of 5.46, which means that the greatest skull length will correspond to this number. I have found a few more measurements now, but for the moment, I would like to share with all of you my first experiments. The original publication was in KingT forum (http://animalbattle.yuku.com/topic/21/bo...1X6N1cXK8w). I will put my new data latter. Enjoy the reading. 1. Proportions of the tiger – head length: Check this image of Baikal: [img]http://imageshack.com/scaled/large/838/a958.png" class="lozad max-img-size" alt="" title=""> *This image is copyright of its original author As we can see, the head-body length of this tiger is about 5 times its head length. Take in count that the body of Bailkal is crouched, so if it were stretched, they will match perfectly with the five bars on its back. This suggests that Mazák assumption that the large Amur tigers had heads that represents about 1/5 of the head-body seems to be correct. Now, let’s see if this value is accurate. Now, check the proportions of “head-body – head length” the other captive Amur tigers: * Amur No. 11: 4.89 * Benjamin No. 102: 4.79 * Amur No. 143: 4.20 Average ratio: 4.63 – range 4.20-4.89 This is close to the 1/5 estimated by Mazák. Sadly, these are the only captive specimens that have its head-length available. Now, let’s use the CBL of all the specimens, including those of Dr Christiansen, to achieve the ratio of “head-body – CBL”: * CN5698: CBL=350.9 mm – HB-CBL= 5.81 * CN5697: CBL=334.2 mm – HB-CBL= 6.16 * CN6049: CBL=337.8 mm – HB-CBL= 5.77 * Amur No. 11: CBL=322.5 mm – HB-CBL= 6.82 * Benjamin No. 102: CBL=331.2 mm – HB-CBL= 6.07 Average ratio: 6.13 I consider these measurements more reliable, as are based in the actual bones compared with the body length. Head-length only is very variable and can change depending of the musculature of the face. Body length can change to, but the difference in musculature is less than in the head. Now, the wild ones, to get the “head-body – head length”: Zheny-1: HL=41 cm – HL-HBL= 4.78 Dale: HL=45 cm – HL-HBL= 4.44 Aleksei: HL=41 cm – HL-HBL= 4.51 Igor: HL=46 cm – HL-HBL= 4.39 Maurice: HL=41 cm – HL-HBL= 5.07 Sasha: HL=48 cm – HL-HBL= 4.13 Misha: HL=46 cm – HL-HBL= 4.17 Valodia: HL=43 cm – HL-HBL= 4.51 Andrey: HL=40 cm – HL-HBL= 4.98 Victor: HL=38 cm – HL-HBL= 5.00 Zheny-2: HL=37 cm – HL-HBL= 4.81 Average ratio: 4.62 – range 4.13-5.07 Interesting both captive (4.63) and wild (4.62) specimens have about the same “head-body – head length” proportions. The range of wild specimens is more variable because the sample is larger. This data show that Mazák was correct, as 4.6 is just slightly less than the 1/5 estimated by him. Sadly, we don’t count with this data for the other tiger populations. Taking in count that we estimated an average head-body length (in straight line) of 233 cm, based in the large femur, for the largest Ngandong tiger, we can obtain the head length based in the Amur tiger ratios: * Wild specimens: ratio 4.62 – head of 504 mm. * Captive specimens: ratio 4.63 – head of 503 mm. Now using the average ratio of 1.16 like the relation of “head length and GSL”, we can get the following GSL estimations: * Wild specimens: 504 mm / 1.16 = 434.5 mm. * Captive specimens: 503 mm / 1.16 = 433.6 mm. The average GSL would be of 434 mm, which is only 6 millimeters less than the previous estimation of 440 mm. This is evidence that tigers are very symmetrical animals and there is no doubt that these same proportions are shared with all the other tiger populations. So, here are the body proportions of the tigers, based in Amur specimens: * Head-body length – head length = 4.62 * Head-body length – Condylobasal length = 6.13 * Head length – greatest skull length = 1.16 Obviously these values can be variable depending of the specimens, but at least they are useful to estimate body size of extinct Pleistocene tigers. 2. Proportions of the tiger – Sunda tigers: You will remember the document of Sody (1949) that presents a large database of tiger skulls from Sumatra, Java and Bali. Besides, it presents the body size of 13 specimens, 9 of them associated with its skull. Here is the full list of specimens:  *This image is copyright of its original author Interesting as it is, the values of the male Sumatran specimens are all lower than those of the Amur tigers, suggesting that this race had a relative larger head in relation to its body. On the other hand, the only Javanese male tiger available match perfectly with the average values of the Amur tiger, suggesting that this “pure” race of Sunda tigers kept the same proportions than the mainland tigers. The Sumatran tigers, been a natural hybrid of mainland and Sunda tigers, probably evolved a different body proportions and completely different cranial characteristics, that have been presented by Mazák & Groves (2006) and Mazák (2008). The values of the females are more confuse as there are not comparison parameters, as with the males. Only one female (Padang, Sumatra) fit well into the ratios of the male specimens, but the other specimens, especially those from Bali, are obviously very inflated and represent specimens measured “over curves” or from skins. As we don’t know the proportions of skull-body for females, it is difficult to get an accurate conclusion, especially in the case of the other two specimens from Sumatra and Java. Conclusion: We can conclude that Sumatran tigers seem to have larger heads in relation to its body, probably comparable to the African lions (My own data, unpublished). This proportion is shared also with the only female tiger apparently also measured between pegs. The measurements of the two Bali tigresses are definitely not reliable and were taken from skins or over curves. This was clearly stated by Mazák in two documents. As for the Javanese tigers, only the male seems to have been measured between pegs. The female skull, using the ratio of the male and those of the Amur tigers, gives a head-body of c.1470 mm, which is 22 cm less than the presented figure, which suggests that the measurement was taken from a skin. For comparison, three South Chinese tigers, measured between pegs, present the following ratios: Location GSL HB Ratio Amoy-1 343 1850 5.39 Shanxi 346 1990 5.75 Amoy-2 321.7 1760 5.47 Average ratio is of 5.54 It seems that the Javanese tiger (5.44) is slightly less than the average ratio from China, and these last two fit perfectly between the ratios of the Amur race (5.19-5.93). Mainland tigers (Amur and China overall) seems to have a ratio of 5.47 (n=8) between the Greatest Skull Length and the head-body length. For the only Javanese male tiger (5.44) the figure is the about the same and suggests a similar evolutionary pattern that probably arises for the first time in the last (and largest) specimens of the Wanhsien tiger. If we put together the five Amur, 3 South China and 1 Javanese specimens, the ratio of head-body - GSL is of 5.46. We can conclude, with some degree of certainest, that we can multiply 5.46 (or 5.5 if you want just one decimal, the difference in the result is minimal) to any GSL specimen and we will have a plausible head-body length in straight line. 3. Proportions of the tiger – the new ratio reliability: Now that we have a ratio of 5.46 for the “Head-body – GSL” for the tiger (Amur, China and Java together), we can prove this value with known specimens. Did you remember the Gondol tiger?  *This image is copyright of its original author Source: Buzas & Farkas, 1997. This is the largest Balinese tiger on record with a GSL of 312 mm, slightly larger than the largest skull recorded for the Venezuela jaguars of Los Llanos (312.5 mm GSL and 1700 mm in Head-body “between pegs”). The head-body of this large tiger is reported as 1740 mm. If we apply the new ratio, we get: GSL 312 * 5.46 = 1704 mm. As we can see, the result is just slightly smaller (less than 4 cm) than the reported size. Although the hunter (Vojnich) doesn’t report the method of measurement, this data suggest that it was taken in straight line. The total length was of 245 cm, which is slightly longer than the record calculated by Mazák (230 cm). Please take in count that Mazák never knew about this large skull. At the end, the result was slightly lower, but overall it was accurate. Now, let’s prove with other large skulls: * Record Bengal from Mazák – 378 mm = 2064 mm HB. * Record Amur from Mazák – 383 mm = 2091 mm HB. * Record Amur from Kitchener – 406 mm = 2217 mm HB. * Record Bengal from Hewett – 413 = 2255 mm HB. These results match very well with the known maximum sizes for the species. For example, the longest Bengal tiger measured by scientist (HB) was of 204 cm (Karanth, 1993), while the largest Amur was of 208 cm (Kerley et al, 2005). For the old records, the longest Bengal tiger was of 221 cm in HB (Brander, 1923), while the longest Amur tiger reported by Mazák (1981) was of probably about 220 cm in HB (total length of 330 cm). These are only a few examples that shows that the ratio of 5.46 produce reliable results. However, we must take in count that even when tigers are very symmetric animals, there are variations. For example, the longest tiger on record between pegs (322 cm in total length; 213 cm in head-body) had a skull length of 381 mm, which produce a ratio of 5.59. This fits very well with the overall data, but is higher than my new ratio. Like a form of conclusion, I will quote Sterndale (1884): “I quite expect to be criticized, but if the crude idea can be improved on by others I shall be glad”. I think that his words apply very well to my hypothesis. With more data, this method and ratio will be better in the future. Greetings to all. 
Baikal could be another form of genetic mutation among the captive Amur tigers.
Celebrate with me, my friends, this is my post No. 100 in the forum!!!
 *This image is copyright of its original author I am the first in reach this number of post.
Yeah, I am pretty sure of that now. [img]images/smilies/tongue.gif[/img]
(04-22-2014, 10:54 AM)'GrizzlyClaws' Wrote: Baikal could be another form of genetic mutation among the captive Amur tigers.I think not. Baikal is one the few remaining of the giant genes of the old wild Amur tigers. This genes are very important as they are now absent from the wild populations.
4. Proportions of the tiger – final document:
Here is my final document. On it is all my database of tigers with head-body and skull related. The final result was that the relation between GSL and HBL had a ratio of 5.4. This produce an accurate estimation of a head-body length of a tiger, between pegs, from a known GSL.  *This image is copyright of its original author  *This image is copyright of its original author Obviously, if peter or other posters provide more measurements, this ration will be improved and more accurate, but for the moment, with the available data, the ratio of 5.4 is very reliable. Greetings to all. [img]images/smilies/smile.gif[/img] 
Great info. Look at the assam head to body length ratio.
Seems that the pictures do not lie, Assam tigers, especially kaziranga, do have the largest skulls to body ratio. |
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