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They met by chance 30 years ago: the PhD student exploring a deep-sea canyon off Newfoundland, and the underwater life he suddenly encountered hundreds of metres deep.
It was love at first dive.
Jean-Marc Gagnon had discovered the giant file clam, never before seen in Canada, and he wouldn’t forget that moment.
Today Gagnon and Fisheries and Oceans Canada have news about the 15-centimetre-long clam. It’s a distinct North American animal, not (as they thought) the same as a clam that looks just like it in Europe.
But beyond the news of a clam’s newly proclaimed identity is the story of a long relationship.
We caught up with Gagnon at the Canadian Museum of Nature where he is curator of invertebrates.
Their first meeting
Gagnon was 800 metres deep in a submersible, exploring Newfoundland’s Bay d’Espoir.
“You’re looking at a rock wall, an underwater cliff, and they are in some places almost covering that rock. These are images that you can’t forget: The colour, the diversity, the beauty of those dives. And I still have the video. You don’t forget that.”
When another scientist sent him modern video of the same clam and asked what it was, his response was “There it is again! It’s been a long process, so I guess — and my wife may not like that — but it’s like a marriage.”
An ongoing relationship
Gagnon didn’t keep DNA samples 30 years ago, and there was no way to test it then anyway.
But he kept thinking about the clam, and in 2003 he identified it as belonging to a well-known European species. However DNA analysis now shows they are different — it’s unique and it’s Canadian.
Although the European and Canadian clam probably had the same ancestors long ago, the Canadian clam shares genes most closely with its lookalikes in the Gulf of Mexico and the Pacific. This suggests a slow movement over millions of years across the Pacific and into the Atlantic.
On eating the newly discovered Canadian clam
“They have a reasonably large muscle in the middle, a little bit like a scallop,” says Gagnon. “They are distant cousins. But it would be very expensive to collect them for that purpose.” When asked if he was tempted to try just one that he collected, Gagnon explained, “It turns out that I can’t digest scallops and lobsters and crabs, even though these are things I’m working on.”
Quick facts about Canada’s giant file clam:
• Its name comes from the sharp ridges on its shell, and is “giant” because there is also a smaller file clam.
• It lives in water 400 to 1,200 metres deep. This include a canyon 200 kilometres east of Nova Scotia called the Gully Marine Protected Area.
• It is likely related to clams that look the same along the United States Atlantic coast. It is “fairly abundant” in the canyons of deep water, Gagnon says.
The new identify of the clam is published in a research journal called Zootaxa.
tspears@ottawacitizen.com
twitter.com/TomSpears1
查看原文...
It was love at first dive.
Jean-Marc Gagnon had discovered the giant file clam, never before seen in Canada, and he wouldn’t forget that moment.
Today Gagnon and Fisheries and Oceans Canada have news about the 15-centimetre-long clam. It’s a distinct North American animal, not (as they thought) the same as a clam that looks just like it in Europe.
But beyond the news of a clam’s newly proclaimed identity is the story of a long relationship.
We caught up with Gagnon at the Canadian Museum of Nature where he is curator of invertebrates.
Their first meeting
Gagnon was 800 metres deep in a submersible, exploring Newfoundland’s Bay d’Espoir.
“You’re looking at a rock wall, an underwater cliff, and they are in some places almost covering that rock. These are images that you can’t forget: The colour, the diversity, the beauty of those dives. And I still have the video. You don’t forget that.”
When another scientist sent him modern video of the same clam and asked what it was, his response was “There it is again! It’s been a long process, so I guess — and my wife may not like that — but it’s like a marriage.”
An ongoing relationship
Gagnon didn’t keep DNA samples 30 years ago, and there was no way to test it then anyway.
But he kept thinking about the clam, and in 2003 he identified it as belonging to a well-known European species. However DNA analysis now shows they are different — it’s unique and it’s Canadian.
Although the European and Canadian clam probably had the same ancestors long ago, the Canadian clam shares genes most closely with its lookalikes in the Gulf of Mexico and the Pacific. This suggests a slow movement over millions of years across the Pacific and into the Atlantic.
On eating the newly discovered Canadian clam
“They have a reasonably large muscle in the middle, a little bit like a scallop,” says Gagnon. “They are distant cousins. But it would be very expensive to collect them for that purpose.” When asked if he was tempted to try just one that he collected, Gagnon explained, “It turns out that I can’t digest scallops and lobsters and crabs, even though these are things I’m working on.”
Quick facts about Canada’s giant file clam:
• Its name comes from the sharp ridges on its shell, and is “giant” because there is also a smaller file clam.
• It lives in water 400 to 1,200 metres deep. This include a canyon 200 kilometres east of Nova Scotia called the Gully Marine Protected Area.
• It is likely related to clams that look the same along the United States Atlantic coast. It is “fairly abundant” in the canyons of deep water, Gagnon says.
The new identify of the clam is published in a research journal called Zootaxa.
tspears@ottawacitizen.com
twitter.com/TomSpears1
查看原文...
