Estimating Male size based off the Female - Printable Version +- WildFact (https://wildfact.com/forum) +-- Forum: Information Section (https://wildfact.com/forum/forum-information-section) +--- Forum: Terrestrial Wild Animals (https://wildfact.com/forum/forum-terrestrial-wild-animals) +--- Thread: Estimating Male size based off the Female (/topic-estimating-male-size-based-off-the-female) |
Estimating Male size based off the Female - Pckts - 05-18-2016 Most of you may have seen the great work @tigerluver is doing, estimating male tiger size based off females so I figured that I'd move all of them here and continue the discussion. So far *This image is copyright of its original author Tigerluver writes "A while ago, I took the length of the two from the picture and estimated that Amur male by isometry. From the photo, he is 1.17x longer, which equates to 1.6x in weight. Taking the 115 kg average for Amur female in STP, the estimate would be 185 kg for that male. " "the Amur in that photo has chest diameter 1.23x the female, translating to 1.86x the mass and 214 kg with the 115 kg number for the female. Averaging length and chest diameter gives 200 kg for the male, which I guess would be a large Amur male based on what we have now. " *This image is copyright of its original author 2 year old Pandit and mother, Sharmili. Tigerluver "Lengthwise, he's 1.18x length without correcting for perspective and angle. Maybe 1.13 would be a corrected value. In terms of chest diameter, the son 1.20x his mother's size with correction. Perhaps 1.15x can be the number to put here to deal with perspective. Same methods as above result in a length estimate of 188 kg, chest estimate of 198 kg, averaging 193 kg. " *This image is copyright of its original author A very young saturn with his female from Tadoba Tigerluver "I split the image and straightened the tigers. He's 1.12x her length and 1.20x her chest diameter. Length based estimate (if female is 130 kg) is 183 kg and chest diameter estimate (again assuming the female is 130 kg) is 225 kg, averaging 204 kg. " *This image is copyright of its original author The Duisburg Zoo male Amur tiger Tigerluver "I measured the female to be around 160 cm, which seems like a ~115 kg female basing off the slightly shorter female Jasmin and the STP tigresses. So the male is 1.31x the female's length and 1.32x the female's chest girth from examining the photo. If I were to estimate the Duisburg male based on this female, we get: Length based: 1.31^3 * 115 kg = 260 kg Chest diameter based: 1.32^3 * 115 kg = 265 kg Now with his body length I can apply some estimates from data of other male tigers. Based on the STP males, isometrically scaling his 210 cm frame based on the average of 7 males of the study (avg. body length = 196 cm, avg. mass = 182 kg), he would weigh 224 kg. An issue with using the STP males is that the wild Amur seems have lost a lot of the robusticity found in captive Amurs and the rest of the tiger subspecies. In other words, STP males are very lanky compared to their captive Amur cousins, and the Duisburg male would likely be more like other captives Amurs rather than the wild STP males. The Duisburg male is also taller proportionately than the STP males. To account for height in the equation, I used the following data. 6 STP males averaged 94 cm at the shoulder and weighed 184 kg. Isometrically estimating Mr. Duisburg from these numbers and his 110 cm height results in a mass of 295 kg. This somewhat accounts for the underestimation by the body length estimate. Combining both body length and height estimates gives a mass of 260 kg. Coincidentally on par with the estimate based on the female by his side. Based on some captive Amurs, the mass values are bit higher. Looking off the table @GuateGojira provided in the Amur tiger thread and the three males of Christiansen, I came up with a average body length and weight for captive Amurs where were as follows: n = 6 Body length = 195 cm Mass = 223 kg Isometrically scaling the Duisburg male from these figures results in a mass of about 280 kg. Had he had Bengal tiger proportions, he would likely be heavier and significantly so at 280-320 kg. Comparing him to Sauraha for example, shows a body length with the potential to harbor a 320 kg cat. The problems I see with using Bengal tigers for comparisons is that the Duisburg male for one, does not seem as bulky as Bengal tigers and the fact that he still is an Amur in the end, and would likely keep to their somewhat leaner built. I have to revisit the photos, however. In the latter two photos the Duisburg males look bulkier than the first photo. Measuring the chest diameter/body length ratio, he is at least 5% less bulky in the photo with the female than in the photos he was alone. Bulking him up in the photo analysis and comparing him with the female gives a chest diameter mass of 306 kg. Averaging this value with his presumably constant body length then gives an average mass of 283 kg. All in all, isometry based on Amurs gave me a mass range of 260-280 kg for the the Duisburg male. (I tried a new method of creating clear subtopics without needing subheading by bolding the first few words of the new subtopic. I hope it made the read easier.) " *This image is copyright of its original author T25 with female T19, said to be larger than her sister, T18 (weighed 170kg) Tigerluver "First what is on the plain of the image (no adjustments). T25 is 1.085x longer and 1.093x larger in chest diameter. In terms of correction, T25 has his head more tucked in, so from the plain of the image one could say he is 1.09x longer. Now in terms of perspective, T25 is further back than T17. I think compensating by increasing the length difference to 1.11x and girth difference to 1.113x would be okay, maybe a bit too conservative but we'll stick with this for the first set of calculations. So to estimate mass: Length based mass = 1.11^3 * 170 kg = 233 kg Chest based mass = 1.113^3 * 170 kg = 234 kg Both values are functionally the same. Now a caveat is that if you look at how much difference being even a meter behind another object will shrink the object further back, the aforementioned compensation is likely too little. Maybe compensating both difference ratios to 1.13x-1.15x would be more accurate, which is a mass of 245-260 kg, similar to T24. " *This image is copyright of its original author Kingfisher and Umarjhola Female from Kahna tigerluver "Top photo: Without correcting anything for perspective: The male is 1.08x the length of the female but the male is at a shortening angle. His chest diameter is 1.41x that of the female's, however. Bottom photo: Male's length in this one is 1.40x the female's, but the female is at a shortening angle. Male's chest girth is 1.37x that of the female's. Not exactly sure how much to compensate for the male being closer in the photo. Perhaps the male is 1.10x the female's length (average the two photos and deduct for his positioning) and the his girth is 1.25x the female's with the same compensations. So say the female is 130 kg, isometry results in: Length based: 1.10^3 * 130 kg = 173 kg Chest diameter: 1.25^3 * 130 kg = 254 kg Avg. = 214 kg If I compensated the male too much, we could say 1.15x length (198 kg) and 1.3x girth (286 kg) at best, which using the above method would come to 242 kg. I'd put this number as the high end and would prefer the more conservative numbers above. All in all, the male is stockier than the female but not much longer. " This is what we have so far, I'll continue to post what I can find and hopefully we can use this technique more often. My other thought would be if there is any correlation for limb girth or shoulder height to body weight. Once again, GREAT WORK @tigerluver RE: Estimating Male size based off the Female - Pckts - 05-18-2016 Here's a pretty decent one for Waghdoh *This image is copyright of its original author Here's Munna (at least you might be able to do body length) *This image is copyright of its original author Not sure where these guys are from but maybe your program can adjust her direction? *This image is copyright of its original author *This image is copyright of its original author These would be a good lion comparison but I know the mane will make it difficult to ascertain chest girth or shoulder height, so may be body length only? *This image is copyright of its original author *This image is copyright of its original author *This image is copyright of its original author Maybe this one? *This image is copyright of its original author
RE: Estimating Male size based off the Female - Pckts - 05-18-2016 Waghdoh with his daughter, Sonam *This image is copyright of its original author She was 3 years old here, this was right after she got into a fight and was badly injured (pg 5 on B2 thread to see her injuries) RE: Estimating Male size based off the Female - Pckts - 05-18-2016 Male with the bold stripes is unknown, the other, smaller male is Pattewalas son from Mukki range. @tigerluver may be for the smaller male you could use the 185kg-200kg mark then compare the larger one? *This image is copyright of its original author *This image is copyright of its original author *This image is copyright of its original author Obviously the intruding male is much thicker RE: Estimating Male size based off the Female - tigerluver - 05-18-2016 I'm going to have to think of a format so I don't need to repost images, but for now, I'm reposting images. All estimates are assuming the female is 130 kg. I'll do the easier pictures now and try to figure out the harder angles later. Thanks for making the thread @Pckts. Wagdoh: *This image is copyright of its original author He's about 1.3x the female's body length with slightly adjustments to make up for the positioning and him being a bit behind. I can't see their chest diameters but I worked with what I can make out the stomach area and there is also a 1.3x difference. Basing off a 130 kg female, 1.3x difference results in a mass of 286 kg. Munna: *This image is copyright of its original author From the photo, Munna is 1.23x the female's length, giving a mass of 243 kg. I'd be a bit surprised if he really was that large, perhaps the female is just smaller than average. *This image is copyright of its original author The left male is 1.11x longer and 1.06x thicker. Mass estimates respectively are (saying the smaller male is 185 kg) 253 kg and 220 kg, averaging 237 kg. The lions: *This image is copyright of its original author Only body length, and he's 1.54x longer. Assuming the female is 120 kg (is that average for a lionness? I don't have my books with me), he's 185 kg. *This image is copyright of its original author Is the male closer to the camera? Going off the frame, he's 1.18x longer and 1.26x thicker at the chest. The according estimates would be 197 kg and 240 kg, averaging 219 kg. Again, assuming a 120 kg female and the male is not a bit closer to the camera. RE: Estimating Male size based off the Female - Pckts - 05-18-2016 He looks to be a bit closer to the camera but its very hard to know for sure. Great work, Munna is a large boy, I wouldn't be surprised if he was in the 220-240 range in his prime. I think you can use the 130kg mark for Lioness as well if you didn't want to split hairs *This image is copyright of its original author *This image is copyright of its original author
RE: Estimating Male size based off the Female - Pckts - 05-19-2016 Here is Kankatti Male and Red eye (in the back) Probably just use the 185-200kg mark again for the smaller male *This image is copyright of its original author They may be to far apart to get an accurate gauge RE: Estimating Male size based off the Female - Pckts - 05-19-2016 You probably can't get body length but you should be able to get chest girth *This image is copyright of its original author BMW male with Baghin nala female RIP (May/2015) RE: Estimating Male size based off the Female - brotherbear - 05-19-2016 This is Van, a huge male grizzly of Katmai National Park, Alaska with a choice female. *This image is copyright of its original author
RE: Estimating Male size based off the Female - Pckts - 05-19-2016 Try finding them standing sideways, I think that he'll have a hard time determining body length or chest girth from straight on RE: Estimating Male size based off the Female - brotherbear - 05-19-2016 (05-19-2016, 12:50 AM)Pckts Wrote: Try finding them standing sideways, I think that he'll have a hard time determining body length or chest girth from straight onhttp://www.buckwildepresents.com/blog/2013/07/30/great-bear-stakeout-van-still-the-man/ Yeah, I can't seem to locate any good comparisons. Van probably weighs roughly 1,000 pounds. *This image is copyright of its original author *This image is copyright of its original author
RE: Estimating Male size based off the Female - peter - 05-19-2016 TIGERLUVER Many thanks for the effort on the Duisburg Zoo male Amur tiger. I was there about half a year ago and asked a few questions about this tiger. As he was in his prime before the keepers were born, I got no answers. In some time, however, I will contact the director. He should be able to find out a bit more. I'm in particular interested in the skull. Calculations based on the correlation between (total) length and weight and chest girth and weight in tigers always are a tricky affair. One needs to have a large and reliable database and it also is important to distinguish between wild and captive animals. Based on what I saw in skulls, I would definitely add age as a factor. Although some immature Indian and Amur male tigers can reach a great size, there's no question that older animals are larger as a general rule. They also seem to be more dense in all departments. As it is likely you will get more orders in the near future, I decided to post a bit more on Indian and Amur tigers. Hope you can use it. a - V. Mazak on Amur tigers V. Mazak, who had contacts everywhere, thought the Duisburg male could have been the largest captive Amur tiger of his day. We better take his word for it. After he understood, and, in the third edition of his book, acknowledged he had been taken for a ride by Baikov and a few others on the size of Amur tigers, Mazak developed a mild obsession with size. We're very happy he did, as it resulted in a lot of information on the size of captive Amur tigers. Mazak also measured over 400 (lion and tiger) skulls in different museums. In the end, he was as informed as anyone. His focus was on the maximum size of big cats. Although some lions and Indian tigers also reached a great size, Mazak concluded wild Amur tigers were the largest wild big cats of his day. We have to add that he based his conclusion on information provided by Russian experts (Mazak spoke Russian and also was in Russia). Most of the weights mentioned in the third edition of his book ('Der Tiger', V. Mazak, 1983, pp. 189), however, were considered 'unreliable' or 'moderately reliable' by experts in 2005. It also is a fact he mixed weights of both captive and wild Amur tigers. His information on the size of captive Amur tigers, however, is reliable. We know 8 males ranged between 96-110 cm. at the tip of the shoulder while standing (females ranged between 82-88 cm.) and we also know 3 males ranged between 298-320 cm. in total length measured 'between pegs'. Male tiger 'Amur', who died in the Prague Zoo at age 11,5, was 220 cm. in head and body (tail 99 cm.) and was estimated at 250-260 kg. in his prime. His son 'Benjamin' died at age 7. He was 201 cm. in head and body and had a tail of 97 cm. (head length 42 cm. and hindfoot 38 cm.). The Duisburg Zoo tiger was 210 cm. in head and body (tail 110 cm.) and stood 110 cm. at the shoulder standing (head length 50 cm.). He was estimated at 280-300 kg. Mazak concluded the largest captive Amur tigers ranged between 260-300 kg. and 300-320 cm. in total length measured 'between pegs' or even a bit more. In his opinion wild males could surpass these limits, but he admitted (pp. 189) there was no solid proof. One could question Mazak or not. There's no question he was preferenced to a degree, but he based his opinion on good information he collected himself. I initially had a few doubts on his conclusions, but it is a fact they were largely confirmed. b - Maximum size Baikov and others reported on very large and heavy Amur tigers shot a century ago. Although most records on these large animals were dismissed in 2005 (Slaught et al), a few were accepted. The extra-large animals he and some others shot were remnants of a population that was nearly completely wiped out. Experienced hunters often target the largest individuals. The result is the population will be affected, especially when the total number of animals was quite limited to start with. It is, therefore, not remarkable that those left in the first decades of the last century were not exceptional. This is important to remember, as today's Amur tigers descend from a very limited gene poole. If we add low numbers, habitat destruction, prey depletion and poaching, we're close to an orbituary on size. This is what is seen elsewhere and eastern Russia most probably is no exception. Tigers respond to pressure by declining in size: small animals are more elusive and can live on smaller prey animals. Case closed regarding size? If we use the information collected in the last 2 decades, the answer is yes. The question is if the captured animals represent the population. This question can't be answered, because there is not much known about wild Amur tigers. Is there another way to get to an answer? Not a few experts, including Yudakov and Krechmar, said they saw large individuals. Yudakov saw a male tiger similar in size to the Duisburg Zoo tiger and Krechmar saw prints of very large individuals. If the population grows, chances are Amur tigers will once again adapt to the situation they face. The reason isn't large prey animals and climate, but competition. More tigers will result in more competition and then there is bears. Male brown bears (Ursus arctos lasiotus) average 580-600 pounds and compete with tigers. Some years ago, on AVA, a poster called 'Eagle Raptor' had created a thread on captive tigers. Although his experience related to UK-based Amur tigers, he also had good information about Amur tigers elsewhere. Most captive males (about 60%, he thought) were 480-500 pounds (217-227 kg.). Miquelle told him wild males averaged about 430 pounds (195 kg.). The difference (about 60 pounds or 27 kg.) could be the average difference between captive and wild male Amur tigers. The difference between the largest individuals, however, could be less. If what I have is indicative, the heaviest and most robust animals could be wild tigers. So what is the maximum size of Amur tigers? The largest wild captive females range between 145-167 kg., whereas the largest max out at 170-180 kg., possibly even 204 kg. The heaviest wild female, however, was shorter than average. The heaviest wild male could have been the Sungari river tiger shot in 1943, who was estimated at about 300 kg. Sysoev, Filipek, Sludskij and Stroganov reported on males ranging between 340-384 kg., but they were not there when these tigers were weighed and measured. c - The Duisburg Zoo male Amur tiger In your post on the Duisburg Zoo tiger (of which PC posted a part in this thread), you compared him to 7 wild male Amur tigers captured in the last 2 decades. These males averaged 184 kg. and 196 cm. in head and body. Based on this assumption, you concluded the Duisburg Zoo tiger could have been 224 kg. You also compared him to the Sauraha male, who exceeded 600 pounds the last time he was weighed. This tiger was 197 cm. in head and body. Based on his essentials, you concluded the Duisburg Zoo tiger might have ranged between 280-320 kg. Let's say the average of different attempts worked out at 260-270 kg. (range 224-320 kg.). Finally, you added Indian tigers seem a bit more robust than Amur tigers. Here's a few things I saw: - Length Warsaw (in Carnivora) did a bit of reading and concluded wild Amur tigers are measured 'over curves'. WaveRiders contacted Miquelle and he confirmed Amur tigers are measured 'over curves'. This means the 7 male Amur tigers were measured 'over curves'. The Duisburg Zoo male tiger was 210 cm. in head and body, but he was measured 'between pegs'. This means he, at his size, would have been at least 225 cm. 'over curves' in head and body (as opposed to 196 cm. for the 7 wild male Amur tigers). The Sauraha tiger wasn't measured 'over curves', but he also wasn't measured in a straight line. If he would have been measured 'over curves', he could have been about 205 cm. This means the Duisburg Zoo tiger was significantly longer. At 110 cm. at the tip of the shoulder (measured while standing), he also was much taller than the 7 wild Amur tigers. Finally, he had an exceptional long and heavy skull and very heavy limbs. - Robustness The Amur tigers captured in Russia ranged between 'healthy' and 'unhealthy'. Most healthy tigers range between 180-212 kg. If we include all male tigers, the range is 125-212 kg. Most males captured this century, however, were at the upper end of the range (180-212 kg.). My guess is Miquelle could have been right (about 195 kg. for an average adult male). If we deduct about 5 inches for an average male, one could conclude wild male Amur tigers, at about 183-185 cm. in head and body, average about 190-195 kg. Robusticy index about 1,05-1,10. Captive male Amur tigers range between 180-220 cm. in head and body length and 160-280 kg. I propose to use 195 cm. (in a straight line) and 220 kg. for now. Robusticy-index 1,10-1,15. Wild Indian tigers seem a bit longer and heavier than wild Amur tigers. Based on what I have, I propose to take 195 cm. for head and body length straight and 220 kg. (about 486 pounds). Robusticy-index 1,10-1,15. Captive male Indian tigers in Indian zoos, however, ranged between 165-210 kg. I propose to take 400-410 pounds as average. This average was confirmed in another survey. Assuming they were as long as their wild relatives, the robusticy-index is about 1,0 or just below that mark. The conclusion is no real difference between Indian and Amur tigers. The image we have (Indian tigers larger and more robust), is mainly a result of pictures of very large wild individuals posted in different threads. Most of them, however, are prime animals with a territory. We seldom see photographs of males who didn't make it. Another difference is many Indian tigers live in protected reserves loaded with big prey animals. - Relatives Compared to other big cats, Amur tigers are less 'chesty', longer and often taller. They also have significantly bigger limbs. Indian tigers are denser (confirmed in skulls). The old Amur tigers, wiped out before World War Two, could have been as dense. At their size, it can't be excluded that some would have surpassed 300 kg. All in all, I'd say there is a strong correlation between lifestyle, food and size in all 3 big cats. Lions have to share food and face a lot of competition. There's no reward for size, because of their lifestyle (prides). Amur tigers face empty stores, bears and long winters. There is a reward for size, but big animals would face long winters and nordic long distance walking too. There's no reward for bulk, that is. Indian tigers live in well-stocked reserves with a lot of competition. This resulted in large, heavy and robust animals. At times, lions and Amur tigers can be as big as a large Indian tigers. The difference between them is large lions are visible, whereas large Amur tigers are not: only a fool would show himself in a region where 60 000 have a hunting license. d - A few pictures 1 - Wild Amur tigresses Amur females average just over 120 kg. and do not seem as robust as Indian tigresses and most lionesses. The question is if the picture that emerged in tables is representative. This tigress was severely wounded by a car some years ago. She didn't make it. A large and big animal, she was: *This image is copyright of its original author This tigress was measured, but I don't know if she featured in the tables I saw. She was long and most probably over 120 kg.: *This image is copyright of its original author *This image is copyright of its original author 2 - Wild male Amur tigers This is the official record for a wild Amur tiger. At 11.7 'over curves' in total length and 560 pounds, Baikov still holds the record. The tiger was shot near the Korean border in 1911: *This image is copyright of its original author Records of significantly larger animals also shot by Baikov were dismissed. They had good reasons, but that doesn't mean these exceptional tigers were not there. Based on what he wrote, Baikov most probably also saw and shot animals like the giant below. He was shot in July 1943 in the heart of Manchuria and was estimated at about 300 kg. The photograph is unique in that it shows that rumours on exceptional Amur tigers were not completely unfounded. This tiger, to be sure, was way larger than most males: *This image is copyright of its original author 3 - Captive male Amur tigers This male, at 611 pounds, could have been similar in size to the Sungari river tiger: *This image is copyright of its original author *This image is copyright of its original author The Duisburg Zoo tiger definitely compared. The exceptional thing is he combined great size with robustness: *This image is copyright of its original author *This image is copyright of its original author Here's a few more who combined size with robustness. The first one is quite exceptional: *This image is copyright of its original author This male Amur tiger (Blackpool) was just over 600 pounds: *This image is copyright of its original author I have no info on this one, but the photograph again shows large male Amur tigers can be very robust. Nearly all I saw had exceptional skulls and limbs: *This image is copyright of its original author This giant had killed its mate. He allegedly was over 700 pounds: *This image is copyright of its original author Most captive Amur tigers who reach 240-250 kg. are long, tall and moderately robust. Those who exceed that mark usually are exceptionally long: *This image is copyright of its original author d - Wild male Amur tigers The tigers captured so far were in no way remarkable. At about 196 cm. in head and body length measured 'over curves' (about 183-185 cm. 'between pegs') and 190-195 kg., they are not as heavy as most wild male Indian tigers. The question, again, is if the picture that emerged from the WCS-table is representative. Yudakov and Krechmar, both authorities on wild Amur tigers, are convinced some males are close in size to the large Manchurian tigers shot a century ago. Here's a few males who might reach or exceed the present record (212 kg. for a young adult male who was 183 cm. in head and body 'measured 'over curves'). Notice the difference in built between young adults and mature animals: *This image is copyright of its original author *This image is copyright of its original author *This image is copyright of its original author e - Measurements of captive Amur tigers This table was posted not so long ago. Tiger 'Amur' was weighed some years after they were measured. At Schiphol Airport, he got to 211 kg. Compared to other Amur tigers I saw, the tigers below were shorter and not as heavy. The average of captive males, as Eagle Raptor said, could be 480-500 pounds, maybe a bit less. My take for now would be about 470 pounds (range 360-620, with some possibly up to about 700): *This image is copyright of its original author
RE: Estimating Male size based off the Female - tigerluver - 05-19-2016 I see, so I have to retract my statement about Amurs being more lightly built. That also explains why the STP males were so much lighter than my between peg regression estimates were giving. Now scaling from the STP tigers with the corrected length of 185 cm and still the same average mass gives a mass of 270 kg for the Duisburg male. Seems much more realistic to me, considering <210 cm Bengal tigers have been recorded a handful of times to get over 270 kg. Were the STP heights measured over curves as well? Answering a question I think @Pckts asked somewhere, I've noticed height does not correlate with mass as well as length or girth. Often time taller tigers are more leg than body, and legs don't carry that much mass. This obviously is not always the case, but enough specimens show the tall and lanky trait to skew equations. Limb girth is also too isolated to a specific part of the body to produce an estimate as length or chest girth, but is still okay as thicker arms should usually be on the heftier males. I'd like to discuss the aforementioned Amur records some more. I think I'll meet you in the "Edge of extinction" thread to keep this topic on point. I'll get to the request tomorrow. A bit satisfying that this little exploration of mine is producing something of value to others. RE: Estimating Male size based off the Female - peter - 05-19-2016 Skulls of captive Indian and Amur tigers are different in that those of Amur tigers usually are a bit longer, whereas skulls of Indian tigers are wider, more vaulted, more robust and (relatively) heavier. One could say Amur skulls are very functional (re-inforced in a few places), whereas skulls of Indian tigers are adapted to withstanding more force. This could be a result of the size of the animals they hunt. Skulls of Amur tigers seem to be designed to compete (with other tigers, wild boars and bears), whereas those of Indian tigers seem to be developed to withstand pressure exercised during prolonged struggles. Robustness in both subspecies is expressed in different ways. Indian tigers have thicker necks, larger chests and more robust bodies, whereas Amurs have a (relatively) longer skull, a more developed upper body and bigger fore-arms. If one would add everything Indian tigers could be a bit heavier, but Amur tigers seem more robust because they are re-inforced in some places. The 'old' Amur tigers, largely wiped out before 1930, could have been as dense as many of todays Indian tigers. Another difference is large Amur tigers nearly always have large skulls, which is not the case in Indian tigers. The Hasinger tiger, who was 10.7 in total length 'between pegs' and otherwise quite robust, had an average-sized skull (14 inches in greatest total length). A large Amur skull very often corresponds with a large animal. The owner of the skull below (16 inches in greatest total length) very likely was a very large animal: *This image is copyright of its original author I don't know how limb length was measured in Russia, because I only consider standing height. Guate, who has a very different view, has a lot of info on limb length. Although I agree with you on the correlation between limb size and weight (not very strong), it could be a bit different in Amur tigers in that Amur limbs seem to be relatively heavier than in other tiger subspecies. In this respect, Amur tigers seem similar to some male polar bears. Limbs apparently also count in intra-specific competition. Indian tiger 'Raja' (also known as 'Prince'), average-sized in most respects, has long limbs and exceptional fore-arms and shoulders. In spite of his advanced age, he still is unbeaten. I will get back to you on chests. It seems there is a strong correlation between chest girth and weight, but the correlation isn't as strong and straightforward as in bears. Lions have big chests and have large skulls, but seldom exceed 500 pounds. Indian tigers also have big chests, but they exceed 500 more often. Amur tigers seldom exceed 130 cm. in chest girth, but also reach that mark quite often (in captivity). Maybe total length is a better indicator for weight, at least in tigers. The reason isn't a long body, but age. Adult tigers keep on growing for quite a long time. They add a few inches, but the real reason they are heavier could be density. This is what I saw in skulls. The difference is quite significant. I agree with the conclusion: your exploration definitely produced something of interest. I'll get back to you on chests RE: Estimating Male size based off the Female - parvez - 05-19-2016 Nice topic pckts. I remember wagdoh and Saturn with their female mates. But seeing other ones too is great. It is very interesting to compare male size based on females size. A clear indicative of sexual dimorphism. |