WHO draft report says animals likely source of Covid-19
apnews.com
apnews.com
Here is one [1] that includes a member of the WHO talking about this. And these folks are biologists [2] that have had many discussions about this topic. Their podcasts are a little long winded for me, but they dive into the various hypothesis. If you want to delve into the more fringe theories, there is Fauci himself from 2017. [3]
[1] - https://www.youtube.com/watch?v=XIXKJXsiBFc