Amazing stuff! Was the saber-toothed tiger unfit for life and evolution eliminated this species?
Cancer is not a modern disease!
"With its fearsome, fast-growing fangs and burly forelimbs, the saber-toothed cat (Smilodon fatalis) was built to kill. According to new research, however, there was one foe these prehistoric predators couldn’t overpower.
P.S. There appears to be some controversy as what to call this extinct animal, but to call it a cat as done by AAAS and the authors of the research article is also wrong since it was much bigger than today's cats!
During the Pleistocene, many saber-toothed cats met their doom in California’s sticky La Brea Tar Pits, likely lured there by the distress calls of trapped prey.
In a new study, scientists analyzed these animals’ fossilized spines, ultimately identifying 3722 vertebrae representing at least 849 adult cats.
The team found numerous abnormalities, including dozens of incompletely developed or fused vertebrae and hundreds that had formed incorrectly. Three vertebrae retrieved from three different pits also showed evidence of spinal nerve tumors, which would have caused severe pain and reduced limb function, likely impairing the animals’ ability to hunt.
Carcasses stuck in the tar pits would have been especially tempting. “ A trapped prey animal is very attractive for a predator in pain,” ..."
From the abstract:
"Tracing the health of extinct populations is important. Documenting this in deep time is challenging, but skeletal markers of disease can be preserved in fossils.
Notably, a high incidence of spinal malformations has been recorded among specimens found in the La Brea Tar Pits, possibly because of an accumulation of expressed deleterious alleles that caused disturbances in developmental processes. The exceptional preservation of hundreds of specimens of the La Brea saber-toothed cat Smilodon fatalis allows us to examine pathologies within and across populations, with dire wolves from the same site and extant large-bodied felids serving as a basis for comparison.
We identified three vertebral specimens from S. fatalis with changes indicating a possible spinal nerve tumor (SNT). The prevalence-like estimate was 353 per 100,000 individuals. The observed prevalence of foraminal widening compatible with presumed SNT among the La Brea S. fatalis sample appears high relative to reported human incidence estimates of 0.22–0.38 per 100,000 individuals, although these values are not directly comparable because the fossil estimate reflects skeletal occurrence in a taphonomically biased assemblage rather than clinical incidence.
The reason for this high incidence in Smilodon fatalis is unclear, but in humans, many SNTs are associated with genetic mutations. Due to the presumed inbreeding toward the end of the species’ existence, a similar mutation could have contributed to the development of the presumed SNTs in S. fatalis."
Saber-toothed cats became inbred—and struggled to move—before they went extinct "Population declines led to spike in spinal deformities and rare tumors, fossil study suggest"
Fig. 1 Photograph of the cranial L7 of HC 12233 showing a smoothly outlined left-sided foraminal widening and bone remodeling forming a ‘cast’-like indentation (arrow) of a presumed SNT (black space-occupying lesion in the drawing) at the level of the foramen.
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