For 33 years, Peter A. Rona has pursued an ancient, elusive animal, repeatedly plunging down more than two miles to the muddy seabed of the North Atlantic to search out, and if possible, pry loose his quarry.

Like Ahab, he has failed time and again. Despite access to the world’s best equipment for deep exploration, he has always come back empty-handed, the creature eluding his grip.
The animal is no white whale. And Dr. Rona is no unhinged Captain Ahab, but rather a distinguished oceanographer at Rutgers University. And he has now succeeded in making an intellectual splash with a new research report, written with a team of a dozen colleagues.
They have gathered enough evidence to prove that his scientific prey — an organism a bit larger than a poker chip — represents one of the world’s oldest living fossils, perhaps the oldest. The ancestors of the creature, Paleodictyon nodosum, go back to the dawn of complex life. And the creature itself, known from fossils, was once thought to have gone extinct some 50 million years ago.
Has the long pursuit frustrated him? “No,” Dr. Rona replied as he displayed traces of the animal in sedimentary rocks some 50 million years old. “It’s science. It’s detective work. It’s about racking up one clue after another.”
Still, in an interview at Rutgers, Dr. Rona said he looked forward to eventually capturing one of the creatures alive. “I think it’s likely,” he said, “if we can do the dives.” Dr. Rona, an authority on the deep sea, likes nothing better than to cram himself into a tiny submersible and fall into the abyss.
It takes more than two hours to descend to the creature’s abode, which lies more than two miles down. The environmental stability of that world — including its crushing pressures and icy darkness — means that some of its most famous inhabitants have survived for eons as evolutionary throwbacks, their bodies undergoing little change. For instance, sea lilies, marine animals with feathery arms, date back more than 400 million years.
Dr. Rona has found that P. nodosum thrives in restricted areas of Atlantic seabed. Its only visible feature consists of tiny holes arranged in six-sided patterns that look curiously like the hearts of Chinese checkers boards. He has photographed thousands of the hexagons and found that large ones have 200 or 300 holes.
Dr. Rona’s inability to catch the creature itself means that even though scientists have given it the fossil’s name, they still vigorously debate what it is. The main question is whether the hexagonal patterns are burrows or body parts, vacant residences or animal remains.
Other deep sea sleuths who share Dr. Rona’s fascination with P. nodosum can be found at Yale and the Woods Hole Oceanographic Institution on Cape Cod, as well as institutions in France, Canada and the United Kingdom.
“He’s got the drive of curiosity,” said Adolf Seilacher, a paleontologist at Yale and co-author of the new paper who first contacted Dr. Rona three decades ago to discuss the creature. “Real scientists, naturalists, are extremely curious.”
Dr. Seilacher added that P. nodosum was a most unusual animal, especially because the many holes at the surface of its abode link up below in a labyrinth of subsurface tunnels.
“It’s not just any fossil but a demonstration of a very complex way of life,” he said in an interview. “It’s a building plan, a behavior that makes this animal erect this gallery system. It’s a lifestyle that is very, very old.”
Dr. Seilacher said the earliest forms of Paleodictyon dated to the explosion of complex life in the Cambrian period some 500 million years ago. The animals began existence in shallow waters, he added, and gradually expanded into the dark habitats of the deep sea.
(Source: The NYT)