A mule is a hybrid. It's bigger and stronger than either a donkey or a horse. It is infertile. It's the same with your garden variety hybrid corn or tomatoes. Big easily stotable and shippable product (but without flavour or desirable texture), but is infertile or doesn't breed true.
Not all hybrids are infertile. Maize corn was developed from its wild progenitors through centuries of genetic modification through selective hybridization -- it is not a plant found in nature -- and that required viable offspring. The same goes for other major crops developed by scientists in the past few centuries, like potatoes, tomatoes, and peppers (interesting pattern there, they all originated in the same part of the world).
It's incorrect to conflate hybridization with modern direct gene manipulation (GMO). They both have the same goal, and effectively do the same thing, but are completely different approaches. Hybridization requires the cross-breeding of unrelated varieties or species, and involves both genetic and epigenetic selection. GMO is directly splicing genes of a single organism to produce altered offspring. Don;t confuse the two.
Not all hybrids are infertile. Maize corn was developed from its wild progenitors through centuries of genetic modification through selective hybridization -- it is not a plant found in nature -- and that required viable offspring. The same goes for other major crops developed by scientists in the past few centuries, like potatoes, tomatoes, and peppers (interesting pattern there, they all originated in the same part of the world).
It's incorrect to conflate hybridization with modern direct gene manipulation (GMO). They both have the same goal, and effectively do the same thing, but are completely different approaches. Hybridization requires the cross-breeding of unrelated varieties or species, and involves both genetic and epigenetic selection. GMO is directly splicing genes of a single organism to produce altered offspring. Don;t confuse the two.