I’ve been meaning to cover in depth that paper on the replication of a speciation event in the laboratory, centred upon Heliconius butterflies, and I’ve now finished the document. Once again, here’s the link:
I supsect several here will enjoy this latest addition to the documents. 
There are witnessed speciation events in nature.
Lake Taal in the Phillipines is a fresh water lake that used to be a salt water bay until a volcanic eruption closed it off from the sea in 1754, and this salt water bay gradually turned into a fresh water lake . . . and venomous sea snakes trapped by the eruption evolved with the lake into a fresh water species, and the lake also hosts the only fresh water sardines in the world (the locals call them “tawilis”).
So, we have at least 2 new species that have evolved within a human framework. Below, see photo of Hydrophis semperi:
