Yes, it means that there is one subspecies of Homo sapiens, and that all extant humans are members of that one subspecies.
The other subspecies are often lumped together as “Archaic Homo sapiens”. This would mean Homo sapiens neantheralensis,* Homo sapiens heidelbergensis*, Homo sapiens rhodesiensis, and so on.
Or, these could be considered separate species. There’s no objective way to determine whether these were subspecies or species, and even the ability to interbreed doesn’t mean they were definitely subspecies. Coyotes can interbreed with wolves and create fertile offspring, but Canis lupus and Canis latrans are separate species, because even when coyotes and wolves share the same range they almost never actually interbreed.
And there’s really no concept of sub-sub-species. Instead you’d use “population”.
Not only is it better to stick to the term population, but it is also necessary to not switch/mix the word population and race. The concept of ‘population’ has a clear and useful biological definition (An interbreeding group that live in the same place/time); the concept of race is socially determined and isn’t even stable through time/culture.
Not only that, but it also implies: group genetic homogeneity and a shared common line of decent. Neither of which is true for “the races” (people grouped together based largely on 18th century physical morphology or other cultural standards).
In biology, “morph” (or “phase”) has a technical meaning, referring to specific distinct forms found within a population of a species. An example is the “black panther,” which is just a melanistic color morph of the leopard. Humans don’t show this kind of discrete variation, however, so morph would not be appropriate.
“Type” has no formal biological meaning, except with reference to the type specimen on which a species definition is based. (Homo sapiens, incidentally, has no type specimen defined) or other taxonomic types.
Humans are simply a geographically variable species. There is no simple biological term for this kind of variation besides describing individual populations.
Some humans are a cross between Homo Sapiens Sapiens and Homo Sapiens Neantheralensis, as shown in recent studies cited above. What would a non-human mix be called? I know there are Ligers and Tions that are 50-50 mixes, but if some non-humans animal is 3% another species (or subspecies) what would be the term for this?
Only slightly off topic, but I just can’t think of a good Portmanteau for a baby half Neantheral and half Sapien.
Some modern humans have some neanderthal genes. I wouldn’t necessarily call this a “cross,” which implies a much more recent hybridization.
Hybrids take the name of both parents. A hybrid between a lion and a tiger would formally be considered Panthera leo x Panthera tigris.
In the case that hybrids were fertile, you would still refer to any hybrid offspring or backcrosses by the name of the two parent species, but specify the type of cross (F1 = first generation hybrid; F2 = second generation hybrid; you could also specify a backcross to a parental species). But there is no formal system. For an organism with only a little admixture, you would probably just say there was some introgression of genes from another species.
If there were some sort of true genetic marker, it would stand to reason that it would be consistent (or at least mathematically predictable) whenever members of different groups mated. That’s clearly not the case, as any random look at children of interracial couples will quickly show.
I’ve read recently (maybe two months ago) a short article relating the discovery, if I’m not mistaken in Russia, of remains that might be those of another homo sapiens subspecie. If anybody has a link related to this discovery, I’d be interested.