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

[GrizzlyClaws]

(04-06-2022, 12:38 AM)tigerluver Wrote:

(04-06-2022, 12:29 AM)GuateGojira Wrote:

(04-02-2022, 07:54 PM)GreenGrolar Wrote: here is another interesting account:

*This image is copyright of its original author

*This image is copyright of its original author

https://www.dailymail.co.uk/news/article...dents.html

Out of topic, but in the line with tigers. It is stated that the maximum distance known to be travelled by a tiger is 1,000 km (Nowell & Jackson, 1993). With this in mind and with this type of records of huge travels from Russia and India, is used to prove that there is no natural barriers in Asia (appart from deserts or high mountains) that can stop a tiger for moving from one part to another one, not even the large rivers. Knowing this, there is no reason why a young male Amur tiger could not travel to South China and mate with the females there, or a Bengal tiger traveling to the Myanmar and make its home there. Based in this, and the fact that the differences between "subspecies" are based in very few specimens, that is why modern scientists believe that there are not "subspecies" per se, but just populations with clinal variations or particular adaptations. The genetic evidence will only suggest modern separations caused by humans, and will support the idea that the modern "subspecies" are just artificial populations created by the intervention of humans.

I think that the subspecies issue is a very interesting theme, with real discussions in the academic groups between the "spliters" and the "lumpers". I will like to go deeper in these topic too, and this shows how interesting is to study tigers without the need to constantly put it in irracional conflicts with other animals (like lions, for example).

I wonder if the movement of Pleistocene tigers was similar, more, or less. Without human barriers and better prey base, do tigers move more or less. It also makes the fossil record of P. spelaea and P. tigris in that northern zone more interesting. 

Here is a vegetation map from the LGM.

There is forest all throughout south Asia. The only barriers happen in China and further north as it is steppe tundra. Any tigers who snuck through corridors probably then got isolated.

When we look at morphology of skull, there is a lot of overlap between the southern populations. Just in the occiput itself, southern forms often have a narrow occiput and the fossil record from even China shows similar. It is only Amur and Caspian tigers that seem to lack this so they must have had some significant separation event.

*This image is copyright of its original author

*This image is copyright of its original author

Tagging @GrizzlyClaws here as we have discussed this topic together in depth for quite a while now and he is well-versed on the fossil record.

Sorry for the late reply, so preoccupied in the last several months.

As @tigerluver is not back yet, kindly request @peter to share his expert observation about those newly discovered tiger fossils of the late Pleistocene from the Southwest region of China which was considered as the cradle of the tiger species after the biotic crisis of the Toba eruption.

Probably discovered from some caverns, that's why these fossils were not black colored like those discovered in the muddy peatland.


Here is two P4 premolars, and the larger one is 42 mm.

*This image is copyright of its original author

*This image is copyright of its original author

Here is a fragment of the canine crown, and the AP diameter is already 32 mm, and could likely attain 50 mm in the skull insertion part.

*This image is copyright of its original author

*This image is copyright of its original author

In summary, the late Pleistocene tigers from China were depicted with super massive dentition as expected, and certainly the progenitor for the modern tiger subspecies in the Asian mainland.

Those giant Pleistocene tigers started to re-colonize the rest of Asia millennia after the Toba eruption when the ecosystem in Asia started to recover from that biotic crisis.

However, only the modern Amur tiger looks like an exact replica of their forefather; because they had the similar adaptation in a similar landmass of East Asia.

The Bengal tiger is just as their biological offspring as the Amur tiger, but they coped themselves in a different landmass of South Asia; therefore they became morphologically more shifted from their late Pleistocene ancestors.

The giant Bornean tiger was technically a giant Malayan/Sumatran tiger, and morphologically they were indistinguishable from the modern southern tiger subspecies. The modern Sumatran tiger is now confirmed to be a Mainland/Sunda tiger hybrid. So in case for the giant Bornean tiger, they were result of the re-expansion of the Mainland tiger population after the Toba eruption and hybridized themselves with some remaining population of the Ngandong tiger.

The modern Javan/Bali tigers were belonged to the same Sunda tiger lineage of the Ngandong tiger. So this proves that the Ngandong tiger didn't get completely wiped out during the Toba eruption, and their remaining population mostly got absorbed during the re-expansion of the giant tigers from the Mainland Asia, while some others got isolated and evolved into the smaller Javan/Bali tigers.

From the 1000 pounds giant Bornean tiger to the 250 pounds modern Sumatran tiger, and this only shows how resourceful tiger as a whole species which can strongly cope themselves in different adaptation that ranging from Cave lion-sized to almost leopard-sized. Reply