I could see how a bird can pick seeds of a cactus and fly between continents, releasing a seed. The other similar, and bigger in my view, evolutionary puzzle

I could see how a bird can pick seeds of a cactus and fly between continents, releasing a seed. The other similar, and bigger in my view, evolutionary puzzle is fresh water seals of Lake Baikal in Russia. Thousands of miles away from the sea shore, they are the only fresh water seals in the world. How they got there is a mystery. https://en.m.wikipedia.org/wiki/Baikal_seal https://en.m.wikipedia.org/wiki/Baikal_seal