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ON THE EDGE OF EXTINCTION - A - THE TIGER (Panthera tigris)
ON THE EDGE OF EXTINCTION - A - THE TIGER (Panthera tigris)
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ON THE EDGE OF EXTINCTION - A - THE TIGER (Panthera tigris)
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@GuateGojira are you willing to include comparison with lions in this topic (name of the thread will depend on that)?
In that case i plan on writing a follow-up post on how the lion subspecies being grouped into two could be a comparable case... (03-22-2019, 10:10 AM)sanjay Wrote: I confirm. After a name is decided you create the thread & how about you move the post there with in the blog-style you have in mind. One example from you will make future ones easier.  (03-22-2019, 09:59 AM)Rishi Wrote:(03-22-2019, 09:09 AM)GuateGojira Wrote: By the way, did somebody have this document of 2018 in PDF? I can't found it in the web by free. First things first. I'm waiting for a response on the questions asked in post 2,135, that is. 
@GrizzlyClaws
From which subspecies "sondaica" (formerly, balica; sondaica and sumatrae) subspecies evolved? modern south china/Pleistocene sunda spp/both spp through hybridisation? I think, after Toba eruption South China Tigers (ancestor of remaining subspecies and most ancient of all along with indochinese "corbetti") from Wanhsien tiger (antique tiger or acutidens) remaining small founder population, the only population of tigers left spread across mainland and sunda (when it is together with asia during ice age glacial maximum). *This image is copyright of its original author *This image is copyright of its original author But, I read some where in forum and wiki of oxygnatha that Ngandong (oxygnatha or trinil?) tiger is also the ancestor of sunda tigers? HOW? Through hybridization with south china?? I strongly believe in 2 subspecies (tigris and sondaica) modern tiger spp idea. They may have local traits and adaptation particular to regions (could be due to disruption in connectivity of their sub populations due to humans since 1,00,000 yrs could be also a reason for some differences in formerly wrongly alleged spps as "9") but little local traits and characteristics differences are not enough to consider as spps. and I also support Amur Reintroduction to Hyrcan region. (03-22-2019, 04:05 PM)Sanju Wrote: I strongly believe in 2 subspecies (tigris and sondaica) modern tiger spp idea. They may have local traits and adaptation particular to regions (could be due to disruption in connectivity of their sub populations due to humans since 1,00,000 yrs could be also a reason for some differences in formerly wrongly alleged spps as "9") Please don't... Men (& women) of science mustn't "believe". Quote:...but little traits and characteristics differences are not enough to consider as spps. How so? The new study, isn't made free for public! https://www.researchgate.net/publication...d's_Tigers (03-22-2019, 05:41 PM)Rishi Wrote: Please don't... Men (& women) of science mustn't "believe".Actually, I agree and "support" that taxonomical (classification) haplotype cladistics and phylogeny systematics of Cat Classification Task Force (CCTF) of IUCN Cat Specialist Group. (03-22-2019, 05:41 PM)Rishi Wrote: How so?I'll stick to this and sounds more realistic and scientifical: https://repository.si.edu/bitstream/hand...sAllowed=y And I agree more with classification which is given more importance (relatively) genotypical or molecular mtDNA comparative analysis and microsatellite diversity based (genetical) than phenotypical based (morphological) which deals with anatomical and structural aspects and features as well as behavioral characteristics. Subspecies differentiation in the tiger would have resulted from geographical isolation, genetic drift and local adaptation associated with repeated restriction and expansion of habitats in the last 100,000 years "only", Climate and humans can be some of the reasons behind. In this short time, evolution of 9 subspecies and coining them as spp according to geographical names or adaptations and modifications is pretty far fetched. Since, 2 million years to 0.1 million yrs of true tiger evolution only, only about 4 Pleistocene tigris spp are occurred at maximum but now from single ancestor, evolution of 9 spp clades in just 1,00,000 yrs is ambiguous. And I agree with 2 spp classification of lion too. (03-22-2019, 05:41 PM)Rishi Wrote: The new study, isn't made free for public! I hope and expect @tigerluver to help. 
 (03-22-2019, 04:05 PM)Sanju Wrote: @GrizzlyClaws Javan tiger: pure biological descendant of the Ngandong tiger, but exposed to the insular dwarfism Bali tige: pure biological descendant of the Ngandong tiger, but also exposed to the insular dwarfism Sumatran tiger: mixed descendant of the Ngandong tiger and the post-eruption mainland tiger (Wanhsien tiger) population That's the likely theory for the evolutionary lineage for the modern Sunda tiger. However, the genetic study that is quite certain that the modern Sunda tiger also shared a common ancestor with the modern Mainland tiger as recent as 75 kya, then the aforementioned graphs were likely accurate about the whole context. (03-22-2019, 07:03 PM)Sanju Wrote:(03-22-2019, 05:41 PM)Rishi Wrote: The new study, isn't made free for public! tigerluver's fossil was only 20,000 years old, but these tigers were still giants that comparable to the largest Cave lion. Not sure if they were already the modern Mainland tigers or the Wanhsien tigers in its late stage, or maybe a transitional phase in between, like the "P. tigris sp" mentioned in the chart. 
No time to catch up on the conversation just yet but here is that paper (I think I've posted it before).
The new paper has demonstrated that the Amur tiger being autosomally closer to the South China tiger, but also emphasizing its genetic affinity with the Caspian tiger.
Maybe the back migrated Caspian tiger used to procreate with the remaining Wanhsien tiger population. The more robust Amur tigers from Manchuria might have leaning more toward the parental side of the Wanhsien tiger, while other populations inherited more from the Caspian tiger. (03-23-2019, 01:53 AM)GrizzlyClaws Wrote: The more robust Amur tigers from Manchuria might have leaning more toward the parental side of the Wanhsien tiger, while other populations inherited more from the Caspian tiger. I think, independent of the amur subpopulation region, the reason might be selective demolishing of large tiger specimen genes from population through trophy hunting or poaching and natural selection pressure towards smaller tigers (even it is colder climate) because of low concentration and less diversity prey items and inability of smaller prey to sustain big tigers metabolism like in early holocene. But now, as through conservation prey base are boosting in some areas, there the robust specimens are making a comeback again as it is important for mass and volume to be more in cool boreal forests for better survival and this more prey is becoming adequate to large tigers unlike before. and Yeah, there, wanhsien genes are revealing like in Manchuria.  *This image is copyright of its original author *This image is copyright of its original author (He is most widespread and successful spp than conspecies and evolutionary equivalent or sympatric one in sunda i.e.., "trinil tiger") Thanks! @tigerluver (03-23-2019, 12:29 AM)GrizzlyClaws Wrote: However, the genetic study that is quite certain that the modern Sunda tiger also shared a common ancestor with the modern Mainland tiger as recent as 75 kya, then the aforementioned graphs were likely accurate about the whole context. If, Java and Bali islands were connected with sumatra in glacial maximum, then this founder wanhsien population might have again colonised and bred with ngandong to form bali and javan tigers. So, that there is mainland tiger shared ancestry still existed in all sunda tigers still in 75 kya. (03-23-2019, 12:29 AM)GrizzlyClaws Wrote: Javan tiger: pure biological descendant of the Ngandong tiger, but exposed to the insular dwarfism Oh ! if this is true, then I find 2 spp classification inaccurate. There must be "3" spp with sumatran in one clade and bali and javan together in one clade. Can you please give me PDF about that phylogeny which you referred? But the big question: After Toba super volcanic activity, wanhsien radiation supposed to be the only one to survive and expand, how come ngandong tiger survived that catastrophe to result in 3 spp of sunda tigers? If they survived to do that, Ngandong tiger who formed by insular gigantism undergone insular dwarfism may be because of extinction of mega fauanal prey which maintained large ngandong tigers but adaptive direction shifted as soon as large prey extinct after eruption and left this tigers to lower their body mass according to prey. So, I think climate and geography or habitat didn't play much role as they are unchanged after and before. But, the biggest natural cat of all time becoming smallest true tiger like bali is so pathetic. so sad. Of course it's what evolution is though. |
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