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Pleistocene Big Cats
Freak Felids - A Discussion of History's Largest Felines
Freak Felids - A Discussion of History's Largest Felines
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Freak Felids - A Discussion of History's Largest Felines
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American lion and young African lion
 *This image is copyright of its original author
Cave lion with reddish coat
 *This image is copyright of its original author
@peter @tigerluver @epaiva
The robust form of the Amur tiger compared to its Pleistocene counterpart.  *This image is copyright of its original author  *This image is copyright of its original author
A complete Panthera spelaea from 16.000 discovered in La garma cave in spain:
 *This image is copyright of its original author
(07-21-2017, 02:36 AM)GrizzlyClaws Wrote: Cave lion with reddish coat (08-08-2017, 10:28 PM)GrizzlyClaws Wrote: @peter @tigerluver @epaiva And from what time is that huge Siberian Tiger from? Any measurements for total size, weight, height, etc?? 
Genome-wide signatures of complex introgression and adaptive evolution in the big cats Figueiro et al., 2017
 *This image is copyright of its original author (A) Species tree of the genus Panthera estimated from genome-wide data. All five extant species are represented as follows: lion (Panthera leo), leopard (P. pardus), jaguar (Panthera onca), snow leopard (Panthera uncia), and tiger (Panthera tigris). Numbers above branches indicate the estimated age [in million years ago (Ma)] of the adjacent node, averaged across all genomic windows (100-kb window size, 100-kb steps) that conform to the species tree (95% highest posterior density interval below the respective branch). Colored rectangles on terminal branches indicate phenotypic categories (defined below the tree; see Fig. 3B for more details) affected by species-specific episodes of positive selection. (B) PSMC plot depicting the demographic history of the five Panthera species inferred from genomic data. (C) Genealogical discordance across the genome of Panthera cats, demonstrated by a sliding window analysis (500-kb window size, 100-kb steps) of a full-genome alignment mapped to domestic cat chromosomes (gray lines at the bottom). The y axis indicates the percentage of overlapping windows within a given interval that conform to (blue) or reject (red) the species tree. Photo credits: D. Kantek (jaguar); C. Sperka (others). Abstract: "The great cats of the genus Panthera comprise a recent radiation whose evolutionary history is poorly understood. Their rapid diversification poses challenges to resolving their phylogeny while offering opportunities to investigate the historical dynamics of adaptive divergence. We report the sequence, de novo assembly, and annotation of the jaguar (Panthera onca) genome, a novel genome sequence for the leopard (Panthera pardus), and comparative analyses encompassing all living Panthera species. Demographic reconstructions indicated that all of these species have experienced variable episodes of population decline during the Pleistocene, ultimately leading to small effective sizes in present-day genomes. We observed pervasive genealogical discordance across Panthera genomes, caused by both incomplete lineage sorting and complex patterns of historical interspecific hybridization. We identified multiple signatures of species-specific positive selection, affecting genes involved in craniofacial and limb development, protein metabolism, hypoxia, reproduction, pigmentation, and sensory perception. There was remarkable concordance in pathways enriched in genomic segments implicated in interspecies introgression and in positive selection, suggesting that these processes were connected. We tested this hypothesis by developing exome capture probes targeting ~19,000 Panthera genes and applying them to 30 wild-caught jaguars. We found at least two genes (DOCK3 and COL4A5, both related to optic nerve development) bearing significant signatures of interspecies introgression and within-species positive selection. These findings indicate that post-speciation admixture has contributed genetic material that facilitated the adaptive evolution of big cat lineages." 
Tigers need that increased ocular perception and night vision since they live in a more closed area than lions, same for jaguars. It is easier to track prey in a very open area since it is more distinguishable unlike closed areas, where the nearest branch could also be prey or vice versa, so depth perception is more important here.
Tigers, like leopards and jaguars, also need melanogenesis since they have stripes and spots (and darker coats), and those take more melanin to produce. But I don't know what the "protein metabolism" gene means. (08-10-2017, 07:52 AM)GrizzlyClaws Wrote: @genao87 What the hell? Not the largest...so does this mean that the Siberian Tiger was the largest modern Tiger again? I remember GuateGojira showing that the Bengal Tiger was the larger subspecies. Looking at the fossil of that Siberian, it had to grow just as big as N. Tiger....maybe not as robust....but what the hell do I know. (08-11-2017, 09:23 AM)genao87 Wrote: What the hell? Not the largest...so does this mean that the Siberian Tiger was the largest modern Tiger again? I remember GuateGojira showing that the Bengal Tiger was the larger subspecies. Looking at the fossil of that Siberian, it had to grow just as big as N. Tiger....maybe not as robust....but what the hell do I know. Some largest canine teeth of the Siberian tigers, and if we can figure out their exact size, then the puzzle about the largest Siberian tiger would be solved.  *This image is copyright of its original author  *This image is copyright of its original author
 (08-11-2017, 11:04 AM)GrizzlyClaws Wrote:Incredible upper canine tooth it is huge(08-11-2017, 09:23 AM)genao87 Wrote: What the hell? Not the largest...so does this mean that the Siberian Tiger was the largest modern Tiger again? I remember GuateGojira showing that the Bengal Tiger was the larger subspecies. Looking at the fossil of that Siberian, it had to grow just as big as N. Tiger....maybe not as robust....but what the hell do I know. (08-11-2017, 11:04 AM)GrizzlyClaws Wrote:(08-11-2017, 09:23 AM)genao87 Wrote: What the hell? Not the largest...so does this mean that the Siberian Tiger was the largest modern Tiger again? I remember GuateGojira showing that the Bengal Tiger was the larger subspecies. Looking at the fossil of that Siberian, it had to grow just as big as N. Tiger....maybe not as robust....but what the hell do I know. Then I am assuming that is underworks?? Or is this from some private collectors who refuses to let scientists or anybody touch their collection??? (08-16-2017, 05:19 AM)genao87 Wrote: Then I am assuming that is underworks?? Or is this from some private collectors who refuses to let scientists or anybody touch their collection??? These guys have spent at least $10K or even more to buy those organic jewels, so I don't think they will ever share it with other people, including the scientific community. So the real maximum potential of the Siberian tiger will remain unknown. |
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