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

[tigerluver]

And as a followup, a quick discussion of the vegetation shifts of the Russian Fear  Primor'ye region. These are vegetation studies (1 and 2). Please also refer to the sea level diagram in my last post. Lower sea levels are associated with colder and dryer conditions which cause open landscapes, and warmer and more humid times make forests.

The study region:

*This image is copyright of its original author

Next, the vegetations shifts. We see that prior the Holocene, the region was more open and a scrubland which would limit the presence of the forest-dwelling tigers. As we enter the Holocene (warming), forests take over. This will allow the entry of the tiger. Here is their table:

*This image is copyright of its original author

Now to get to the Primor-ye, the tiger would have to pass through the northeast China corridor. It cannot use any pathway further west as those landscapes are open as in this map:

*This image is copyright of its original author

So we look at the vegetation shifts in northeast China. Per this study, we learn the following:

1. Steppe extended as far as the Songnen plain at the last glacial maximum (LGM) and only the far coastal regions had some forest. The green area is the Songnen plain:

*This image is copyright of its original author

So at this point, the presence of the tiger in this region and further north is unlikely or at least less so. Then as in the study mentioned in my last post, forests finally appeared in the region around 14 kya. However, the denseness of the forest probably took longer to increase as climate had to warm more first. This again would limit the presence of the tiger. 

So what we can put together is that the tiger did not have much of a chance to enter what classify as the Amur tiger's range until the end of the Pleistocene. After that, there does not seem to be a clear moment of separation of the population. However, Chlachula et al. (2016) do note that there was "a broadening of open landscapes and mosaic parklands in the main river valleys during the mid Holocene is linked with the expansion of the Far Eastern Neolithic cultures based on a herding pastoralist economy and who practiced forest clearance for pastures as is well-documented in the nearby Iman Valley between ca. 5,000-4,000 cal yrs BP."

The location of the Iman Valley sites:

*This image is copyright of its original author

The increase in open landscapes due to human presence probably began fragmenting the forests at this point, giving us a geographic barrier between the Amur population and the rest as tigers stick to forest boundaries. The collection of these findings coincides very well with the divergence range of the Amur tiger (3.25 kya-8.12 kya). Reply