Well, it's been almost 30 years since I took my last biology course, but one thing I remember my professor said was that in order for a species became a species was that it had to be "reproductively isolated." In other words, Homo Sapiens was reproductively isolated from Homo Erectus et al.
So, let's take this to chile peppers -- we have capsicum annuum, capsicum chinense, capsicum frutescens, and so on. Capsicum being the genus, while the suffix(annuum, chinense, etc) being the species.
Am I correct in my deduction that these are all different SPECIES, and not just different varieties of chiles?
This reasoning leads me to believe that I can have a Jalapeno(annuum) and an Habanero(chinense) next to each other growing in the garden and have no danger of cross-pollination.
Is my thinking on or off here?
Or is there still a possibility of cross-pollination but there's an anomaly in the offspring? Like breeding a horse with a donkey you get a MULE, but it's STERILE(reproductively isolated)?