A paper by Romina S. Petrigh et al, Ancient parasitic DNA reveals Toxascaris leonina presence in Final Pleistocene of South America, (Parasitology, 2019. DOI: 10.1017/S0031182019000787) reported the discovery of a parasitic roundworm in a coprolite (fossilized feces) from a puma (Felis concolor) in Northern Argentina's Puna region. The fossil stool was dated at 16,573–17,002 calibrated years BP.
The finding is indeed remarkable because "Ancient mitochondrial DNA analysis confirmed the zoological origin of the coprolite as Puma concolor and that of parasite eggs as Toxascaris leonina. This is the oldest molecular parasite record worldwide".
Mental constraints
The age is a key factor here because, based on it, the authors dismiss that the parasite that infected the puma was transmitted by domesticated dogs (or cats) as other authors postulate; the paper states this several times:
"This allowed confirming the presence of T. leonina in prehistoric times, presumably even before that of humans in the region...Therefore, the common interpretation that the presence of T. leonina in modern American wild carnivores is a consequence of their contact with domestic dogs or cats (Okulewicz et al., 2012) should no longer be assumed as the only possible explanation".
The date is supposedly older than the currently accepted arrival date of humans in the region hence no domestic dogs could have transmitted the parasite to pumas ("The first human explorers who ventured into the area ca. 11 000 years ago")
So, the authors cannot avoid the current time frame for human presence in America. But, what if there were humans here 100,000 years ago, would that have affected the puma parasites? They wouldn't of had dogs with them -domestication date of dogs is much earlier anyway. The point is that human presence is irrelevant to their finding.
I mention this because scientists cannot escape from their mental straitjackets and thes authors mention the 11 Ky date as important-it isn't. But, let's go back to the paper:
A natural origin is suggested, and I fully agree with it: "Canids and felids are infected by ingesting rodents and paratenic hosts and also directly by contact with feces with eggs containing infective larvae. "
Regarding its identity as a Toxascaris leonina the paper indicates that "The BLASTN analysis showed an identity range of 96–93% between cox1 fragment of T. leonina European and Asia isolates from different hosts (canids including dog, wolf and European fox, and felids including Eurasian lynx and South China tiger). Pairwise analysis among available T. leonina sequences showed a wide range of identity percentages, from 98 to 93%. A maximum of 1% intra-specific divergence within Iranian isolates has been reported (Mikaeili et al., 2015). Thus, this 4% divergence with ancient T. leonina could be attributed to different temporal and geographic origins."
So American T. leonina are distinct from Asian ones due to "different temporal and geographic origins", which makes sense, after all the puma belongs to a lineage that originated 6.7 Mya. Nowadays it consists of three species: puma, and on a contiguous branch the American jaguarundi (Herpailurus yagouaroundi)). The third species is the cheetah (Acinonyx jubatus) which 100,000 years ago migrated across Beringia into Eurasia and finally into Africa (this is a real "Out of America and Into Africa" event).
Puma surely got the roundworm from some non-human agent (I mean that domesticated dogs had no role in it), yet the authors had to point it out: "At a regional level, these aDNA studies have also allowed confirming the presence of pumas in the southern Puna at the end of the Pleistocene. This has significant implications for the natural history of the region, as well as for inferring the ecological context immediately previous – as far as is known so far – to the first human explorers who ventured into the area ca. 11 000 years ago".
But, as I said further up, humans could have been here in America for one million years and this would have no impact whatsoever on the fact that this team of scientists found ancient roundworm in fossil puma poo.
Patagonian Monsters - Cryptozoology, Myths & legends in Patagonia Copyright 2009-2014 by Austin Whittall ©
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