There are several examples of cross-species breeding resulting in viable offspring that can reproduce. You mentioned two breeds of domestic dog but domestic dogs can also breed with grey wolves. The domestic dog is considered a sub-species of the grey wolf. Coyotes can also breed with the grey wolf. Dingoes and jackals also fall in with domestics dogs, wolves, and coyotes. It isn't just canines either. The Savannah cat is a cross breed between African servals and domestic cats and that is not the only example for felines. Beefalo and Żubroń are examples of cattle/bison crossbreeding. Sumatran and Borenean orangutans are different species that are able to crossbreed.
Hmm very interesting, I was unaware of some of your example such as the Orangutan. Upon further research, at the Genus level "Two organisms from one genus might or might not produce an offspring with sexual fertility, but it is very certain that organisms from two different genera (plural of genus) can never produce a fertile offspring." While species has the same number of chromosomes and will produce fertile offspring. I guess my question, or perplexion, is why every verbally articulate human being on the earth now are solely the same species. Questions 1) Either by selection. 2) Even though genetic diversity. Maybe all our classifications are semantic, I'm still processing this. (Quote source: https://www.differencebetween.com/difference-between-genus-a...)
