Title text:
The inflection point was probably in late 1966 or 1967, so when Neil Armstrong flew to space on Gemini 8, plate tectonics was not widely accepted, but when he landed on the Moon three years later it was the mainstream consensus.
Transcript:
Transcript will show once it’s been added to explainxkcd.com
Source: https://xkcd.com/3159/
Yes, plate tectonics is recent. But it explains how continents move. The comics says that before 1967, no thought they moved at all. Which is false.