The Book of Eels, Patrik Svensson [bill gates best books .TXT] 📗

the eel has not, however, proved particularly cooperative. The sensational artificially produced little willow leaves at the University of Hokkaido barely had time to hatch and register the lack of ocean currents in their tank before they died. The leptocephalus larvae simply refused to eat. It didn’t matter what the Japanese researchers tried to tempt the transparent little creatures with. The willow leaves went on hunger strike and invariably perished.

For years after that, and over many generations of artificially created but all equally short-lived leptocephalus larvae, Japanese scientists dedicated themselves to finding out how to keep newly hatched eel larvae alive. What do they eat? No one knew. Their feeding habits had never been observed in the wild. A range of foods were offered. Plankton, roe from other fish, microscopic rotifers, parts of octopuses, jellyfish, shrimp, and clams. The tiny larvae stubbornly refused sustenance in each successive attempt and predictably died soon after hatching.

It took the scientists close to thirty years to come up with a meal the larvae could stomach. It consisted of a powder made of freeze-dried shark eggs; armed with this, they managed to keep a handful of larvae alive for all of eighteen days in 2001. It was a sensational new record, but they were still, of course, very far from finding the answer to how to coax the transparent willow leaves into transforming into fully grown, edible eels in captivity.

Furthermore, the eels continued to be difficult in other ways. Even though the researchers were now able to make them eat—the prescribed diet was refined over time until at least some specimens survived into the glass eel stage—most still died within a few days of hatching. Only 4 percent of the larvae lasted for fifty days, and only 1 percent for a hundred. The number that reached the size necessary to turn into glass eels was almost zero.

Moreover, the laboratory eels behaved differently than their peers in the sea. The captured females produced significantly fewer eggs in captivity than in the wild. It also soon became clear that all the eels hatched in the laboratory were male. No one knew why, but to remedy it, glass eels were injected with estrogen to artificially produce females. In 2010, Japanese scientists succeeded for the first time in completing the life cycle of the eels when they produced eggs, and in time leptocephalus larvae, from eels that had themselves been created in the laboratory. The eels were also given hormones to make them grow faster, which lead to severe deformities in their offspring: willow leaves that didn’t look anything like the ones caught in the sea, their heads strangely misshapen, and the animals themselves unable to swim. It was as though the eel were refusing to let anyone else control its creation. As though its existence was its own business.

As of this writing, scientists are working hard to find the correct methods, if they even exist, to farm eels, which would be important not only to the Japanese eel industry but also, by extension, to the survival of the eel globally. They are nowhere near succeeding. But every year brings new technologies, new scientific insights and innovations, and for anyone interested in understanding the eel, there is—all the obvious problems notwithstanding—reason for hope. Perhaps some kind of tracking device will be developed in the not-too-distant future that’s small and light enough to follow a silver eel all the way to its breeding grounds in the Sargasso Sea. Perhaps that will allow us to pinpoint more precisely where on the map reproduction takes place, and perhaps once enough eels have been tracked, we can confirm or reject the idea of multiple breeding grounds. Perhaps by then, we will also have a better understanding of what stops or impedes the eel on its journey back to its birthplace. Perhaps we can even do something about it. Perhaps European and American researchers will, like their Japanese colleagues, manage to fertilize eggs from European and American eels and hatch them in captivity. Perhaps one day, these cultivated eels will survive and grow big and healthy enough to be eaten. Or, of course, to be released into the wild.

A scientifically minded optimist would say it’s just a matter of time. With a focused will and enough time, science will find a way to solve every riddle. The eel question has endured in various guises over millennia, but experience tells us we will find the answer, sooner or later. We just need enough time.

The problem, though, is that time is about to run out.

16Becoming a Fool

I remember Nana on the lawn. With her head slightly bowed and her arms raised in front of her. She was holding a branch broken off the apple tree next to her. It was the first time I saw a dowsing rod.

She slowly walked across the grass, away from the tree, turned left and then right, searchingly, as though every step was a step into the unknown. Her eyes were vacant, as though she wasn’t even aware that we were standing there watching.

Suddenly, she stopped; her arms twitched and were pulled down toward the grass. The rod seemed to tug at her, hard and violently, as though trying to wrest free of her grasp. And Nana looked up and laughed and said: “I can’t explain it. It’s not me doing it. I’m not even moving.”

Dad shook his head, walked over to her and grabbed the tree branch with one hand. Then they held it together while they slowly walked around, side by side, in a circle on the grass, like a slow, peculiar dance; when they got back to that spot, they stopped, and Nana’s arms were once again pulled violently downward. Dad looked up and laughed, too, while the branch was still moving.

“I can barely hold it,” Dad said.

When he let go, Nana stopped moving. She held the branch up in front of her and looked at it in wonder.

“I can’t explain it. But I can feel