|Japanese Eel (Image source:Wikipedia)|
One of the prominent landmarks in Tsukuba Science City is an "Unagi" restaurant on Gakuen-Higashi Odori. The "U" in うなぎ is displayed in a trailing calligraphic brush-stroke to resemble a long, slippery eel that happens to be the speciality of this restaurant.
I had forgotten all about this eatery and its long wood-smoke chimney's until I came across this wonderful article in the New Yorker: The Poetic Life of the Lowly Eel (23 April 2015).
What amazed me the most was that until a few years ago, nobody really knew that the common "fresh water eel" began its life thousands of miles away in the great oceans. Every American and European eel is born in the same place in the middle of the Atlantic Ocean, where, at the end of their lives, they return to reproduce and die: the Sargasso Sea. It took a Danish biologist Johannes Schmidt 20 years of research to discover this by searching for for tinier and tinier eel larvae!
Similarly, the spawning grounds of the Japanese eel were found in 1991, near the Mariana Trench, after six decades of searching. Those for the New Zealand longfin eel have yet to be discovered.
Even today we have no idea why eels travels so far out in the open oceans to lay their eggs, or on the impulse that leads millions of tiny larvae to swim back the entire distance, passing through various stages of life in sea as eggs, leptocephali ("slim head") and glass eels, before heading towards freshwater habitats.
This is the sort of thing that makes us wonder at our own mind-boggling ignorance about life on earth!
New Yorker (23 April 2015): The Poetic Life of the Lowly Eel -- http://www.newyorker.com/tech/elements/the-poetic-life-of-the-lowly-eel