One commonly asked question is what is the evidence for a natural versus a laboratory origin of Covid-19?
After spending 2 years looking into the available evidence, I have written a book and given a few talks on this topic. The top points are summarized here, with much more detail and backstory available in the paperback of VIRAL: The Search for the Origin of Covid-19.
At the moment, there is still no definitive evidence for any origin scenario. Therefore, experts and investigators (including expert panels convened by the World Health Organization and the Lancet Covid-19 Commission) agree that both natural and lab origin hypotheses remain plausible and must each be rigorously investigated.
What are the plausible scenarios by which the pandemic virus, SARS-CoV-2, might have emerged in Wuhan in 2019? The fact that an ancestral version of the virus must have existed in bats at some point in history is not controversial.