Is there a canon mention that Kenobi, Windu, Palpatine, the Skywalkers etc. are the same human species as all the other humans in the Skyriver Galaxy like Han Solo?
They look like humans, but we know that they're different in at least one characteristic: midi-chlorian hosting, which I suppose humans can't do as per definition.
Answers only from Canon, please. EU is welcome...
Midi-chlorians are in microorganisms in symbiotic relationship with a living being that hosts them (think Mitochondria; or Chlorophyll in Earth plants; or Kanga Virus mutation in Thuselahs of David Weber's "Apocalypse Troll").
Given that the Force tends to run strong in the families, it's clear that Midi-chlorian affinity/density is heritable; at least somewhat genetic in nature.
However, having a specific genetic trait in no way makes someone a different species.
So, merely being a Force-Sensitive (e.g. having high Midi-chlorian count) does no by itself mean Jedi aren't "human". So, we need to discuss how species is determined in general:
To decide whether the "human" Jedi are the same species as Homo Sapient, we must first look at how "Species" is defined. To misquote from my answer about Superman's species:
The definition of "species" is a bit murky (see "Species Problem" Wikipedia entry in detail).
Let's start with Wikipedia definition of "species (emphasis and ellipses mine - DVK):
In biology, a species is one of the basic units of biological classification and a taxonomic rank. A species is often defined as a group of organisms capable of interbreeding and producing fertile offspring (Note: often, not always. Discussed below).
While in many cases this definition is adequate, the difficulty of defining species is known as the species problem. Differing measures are often used, such as similarity of DNA, morphology, or ecological niche.
In light of those definitions:
Human Jedi clearly can interbreed with human non-Jedi (e.g. Corran Horn's mother was a Muggle, so was Queen Amidala). This makes Human Jedi the same species.
Leaving aside Midi-Chlorian affinity, there is no evidence that Jedi are genetically different from Humans (as a matter of fact, there's canon support for genetic identicalness - they use Midi-Chlorian counters to detect Jedi, whereas they could have used simple genetic tests if that was not the case).
Morphologically, "Human" Jedi are always described 100% human. Both G- and C- canon always stress that 100% of Jedi abilities come from the Force - without the Force they are 100% morphology.
Ecologically, they live in pretty much the same environment as other humans biologically (despite being adapted to wider range of hostile environment, e.g. vacuum, cold or hotness); and fulfill general "LEO/PeaceKeeper" ecological niche as other humans.
Based on all 3 definitions, "Human" Jedi are same species as other "Humans" in TGFFA.
In The Empire Strikes Back, C-3PO says that Luke is "quite clever, you know... for a human being." So at the very least, C-3PO, a protocol droid who would presumably be aware of distinctions between species for diplomatic purposes, considers Luke, a Force-sensitive individual, to be human. (This is in addition to any number of official reference materials that list the species of all human-looking Jedi to be human.)
Of course they are human. They don't "host" midi-chlorians, the midi-chlorians are microscopic organisms that live inside all living things, but are highly attracted to Force-sensitives; the more Force-sensitive a being is, the more midi-chlorians they will attract. George Lucas even stated, way back in 1977; "It is said that certain creatures are born with a higher awareness of the Force than humans. Their brains are different; they have more midi-chlorians in their cells." George Lucas explicitly stated 37 years ago that humans have midi-chlorians in their cells. I don't know what more evidence you could need, but here is a link to Obi-Wan Kenobi's Wookieepedia page, where he is described as a human.
Not sure what its canon-level is, but according to "Star Wars: The Essential Guide to Alien Species", humans are the galaxy's most common sentient species - of which there are thousands of variations & sub-species found throughout Republic/Imperial space. Although it never specifically calls them "Homo Sapiens", it does mention that the human race is believed to have originated on Coruscant, which would therefore make all other human races a subset of that original race.
So, if the intent of your question is "Are they all human, same as us?", then the answer is yes.
If your question means exactly what it says - "Are they Homo sapiens?", as opposed to Homo Starwarsicus or something, then I guess the answer would be No... they're a different kind of human.
Keep in mind, within the context of the lore, everything in Star Wars happened a "long, long time ago in a galaxy far, far away." Within that context, Earth is just one more human 'colony' that hasn't yet discovered (or re-discovered) space travel, and is basically ignorant of the rest of the universe.
They can't be homo sapiens because they are reproductively isolated from all known examples of homo sapiens -- that's the definition of a separate species, regardless of whether or not they have similar DNA.
I see I need to clarify here. It's not that Jedi and Sith specifically aren't homo sapiens. There are no homo sapiens characters at all in Star Wars, because they have no contact with Earth and the homo sapiens species. The characters who look like homo sapiens may have identical DNA to homo sapiens, but they're still a different species, because of the reproductive isolation.
