I wondered the same thing. Certainly, available materials impose limits on both designer and builder. I would also expect that designs that proved successful (and, just returning from a hunting expedition out in the ocean has to qualify as a success), would have a strong vote. I’ve never built a boat out of sticks and bones that I first had to collect. So, availability, length, and strength of these sticks and bones.presents both opportunity and limits. Another influence may have been local style, or tradition?
Whatever all of the influences were, the final products were basically interchangeable. And, canoes followed a fairly similar pattern of similarity. And, frankly, our modern boats follow the parade pretty well too.
The modern Greenland style kayak paddle looks like it has evolved from ancient paddles made of scrap wood.