History was one of my undergrad majors, and I knew exactly what I was looking for with that--I knew which sources existed, I just needed to find them on the web for the citation. The more technical/medical studies take longer to search for and evaluate just because there's so much material out there.
You're the one who said this in answer to whom we give thanks (emphasis mine):
IIRC, (American) Thanksgiving is holiday held to celebrate the end of the harvest season. According to wikipedia, the "who" is a native american named Squanto.
I was correcting your historical inaccuracy about Thanksgiving being a holiday to give thanks to Squanto, and that was all. I was not making a value statement on what we should give thanks for, nor was I arguing whether or not it's a religious vs. secular holiday. Now, you can try to deflect that with these comments you've made above or go off on a tangent to the purpose of Thanksgiving, but it doesn't change the historical facts.