A Darwin man thought he'd found a rotting finger on Sunday when his dog dug a digit-like object out of the sand at Lee Point beach. Fearing the worst he called the police who duly treated the find as serious, until a pathologist on Tuesday confirmed that that the finger-like specimen was indeed "dead man's finger"—a common term for the coral Alcyonium Digitatum.
The coral, usually found in the northern hemisphere between Portugal and Norway, had police stumped on any further details. So we stepped in with Auckland based marine biologist, EJ Goldsworthy to learn more.
VICE: Hey EJ, so what is this stuff?
EJ Goldsworthy: Well if it is what the police say, it's a type of soft coral generally found in Western Europe. It only exists in the North Sea and North Atlantic, but it doesn't have a finger nail. The image shows something different, but unfortunately without the specimen we can't come up with a correct identification. It could be a sea squirt, a sponge, or a soft coral that is related to Alcyonium Digitatum.
This one definitely appears to have a nail. Do they all usually look so much like fingers?
Well I haven't seen anything like this one before. Generally I wouldn't say the coral looks like fingers at all. Also soft coral still generally feels hardish and it's unlikely it would have felt like actual flesh. I guess that floating in the water decaying for long enough it might feel fleshy or limp. Either way I certainly haven't heard of it causing a police investigation before.
Would it have smelt like rotting flesh?
Coral can smell pretty revolting when it's decaying so it could have had some similarities with decaying flesh. After all coral is an actual animal so if it is rotting it might have resembled off meat.
Can you tell me more about the creepy name - dead man's finger?
Well that name has been applied to loads of things. Search it on Wikipedia and you'll see its been applied to types of coral, fungi, seaweed, fruit, and even the gills of crabs. Generally I don't think there's too much of a connection, perhaps with the exception of this case.
Okay, how about it's growth? What sort of environment is it naturally found in?
It needs to grow where it has access to light as it contains thousands of zooxanthellae that need light for photosynthesis. It survives best in areas where the water current is strong and can grow to 200mm in height. The larvae attach themselves to rocks or any other hard substrate, even crabs, and grow, forming a colony.
So how did it get from Europe all the way over to here?
It could be a ton of different ways. Ballast water from ships introduce a massive amount of foreign organisms into new countries all the time. Also there have been heaps of storms lately or it could easily have just come here on the currents. Organisms get introduced to foreign places for heaps of different reasons. It all depends on the organisms and the ecosystems they're introduced into as to whether it establishes itself or not. Maybe it was introduced into the waters near Darwin and has been living it up since.
Finally, do you think the rest of us are dumb for thinking this was a finger?
It's hard to say without having felt and seen the actual thing, but the photo looks pretty human-like! Having said that I would have hoped a member of the police department would be able to tell the difference between a piece of coral and a human finger without the need for forensic examination.
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