Do Palestinians also have Canaantine ancestry as well ?

Yes, Palestinians do descend from ancient civilizations and groups that inhabited historic Palestine, including pre-Judaic Cannanites. For a comprehensive answer about Palestinian genetics and links to Cannanites, see Drew M answer here:
From my experience, it is irrelevant whether they descended from Cannanites or not. I mean It is true that Palestinians are descendants of ancient civilizations and religions that lived in the region for centuries, including Canaanites. However, the idea that Palestinians are the descendants of only one particular group in a region with mass migrations and dozens of different empires and peoples is not only ahistorical, but this line of thought indirectly legitimises the original argument they are fighting against.
This is because it implies that the only reason Israel’s creation is unjustified is because their Palestinian ancestors were there first. It implies that the problem with the argument lies in the details, not that the argument as a whole is absolute nonsense and shouldn’t even be entertained.
The ethnic cleansing, massacres and colonialism needed to establish Israel can never be justified, regardless of who was there first. It’s a moot point. Even if we follow the argument that Palestinians have only been there for 1300 years, does this suddenly legitimize the expulsion of hundreds of thousands? Of course not. There is no possible scenario where it is excusable to ethnically cleanse a people and colonize their lands. Human rights apply to people universally, regardless of whether they have lived in an area for a year or ten thousand years.
If we reject the “we were there first” argument, and not treat it as a legitimizing factor for Israel’s creation, then we can focus on the real history, without any ideological agendas. We could trace how our pasts intersected throughout the centuries. After all, there is indeed Jewish history in Palestine. This history forms a part of the Palestinian past and heritage, just like every other group, kingdom or empire that settled there does. We must stop viewing Palestinian and Jewish histories as competing, mutually exclusive entities, because for most of history they have not been.
These positions can be maintained while simultaneously rejecting Zionism and its colonialism. After all, this ideologically driven impulse to imagine our ancestors as some closed, well defined, unchanging homogenous group having exclusive ownership over lands corresponding to modern day borders has nothing to do with the actual history of the area, and everything to do with modern notions of ethnic nationalism and colonialism.
Semitic people from Canaan invading Egypt, tomb wall at Beni Hassan, 1700 B.C as depicted by the Egyptians (Top photo). Today, 4000 years later, the Palestinian traditional dress (Thobe) is still almost identical.(Bottom photo)

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