> Pangolins and bats don't usually cohabitate, making this somewhat unlikely in nature.
Horseshoe bats are nocturnal animals that roost in caves during the day but sometimes practice perch feeding at night [1]:
> The other strategy is known as perch feeding: Individuals roost on feeding perches and wait for prey to fly past, then fly out to capture it.
Pangolins [2] and palm civets [3] are nocturnal and arboreal. The bat viral RNA sequences come from anal swabs of netted animals so they are primarily gastrointestinal infections. All of these animals are found in the Lancang/Mekong [4] catch basin. Bat guano seems like a good vector for the virus.
Gain-of-function experiments require two viral isolates that recombine during passage. The lab theory assumes that the RNA sequence of the original viral isolates were never shared. I find this scenario unlikely but I am open to changing my mind based on evidence. SARS-1 is evidence of a very similar zoonotic scenario.
Humans that encounter bat guano in this region also seem like a good host for a recombination event.
[1] https://en.wikipedia.org/wiki/Horseshoe_bat#Diet_and_foragin...
[2] https://en.wikipedia.org/wiki/Pangolin#Behavior
[3] https://en.wikipedia.org/wiki/Asian_palm_civet#Feeding_and_d...
So are you proposing that a pangolin from Lancang was transported more than 2000km to a seafood wetmarket in Wuhan?
At face value, this sounds like a very unlikely scenario for a zoonotic event/origin.
[0] https://www.nationalgeographic.com/animals/2020/04/coronavir...
> Shi’s team used the antibody test to narrow down the list of locations and bat species to pursue in the quest for genomic clues. After roaming mountainous terrain in most of China’s dozens of provinces, the researchers turned their attention to one spot: Shitou Cave, on the outskirts of Kunming, the capital of Yunnan, where they conducted intense sampling during different seasons over five consecutive years.
Distance from Kumming to Wuhan: 1,566 km [2].
Distance from Kumming to Foshan (SARS-1): 1,315 km [3].
I am saying that horseshoe bats, pangolins, palm civets, and humans overlap in Yunnan province and along the Langcang/Mekong. This is the most likely ground zero for a natural recombination event. When and how the first SARS-CoV-2 virus made its way to Wuhan is a separate question; I'd think a human on a train is the most likely vector.
[1] https://www.scientificamerican.com/article/how-chinas-bat-wo...
[2] https://www.google.com/maps/dir/Wuhan,+Hubei,+China/Kunming,...
[3] https://www.google.com/maps/dir/Foshan,+Guangdong+Province,+...