Giant squid boasts world’s biggest eye (+video)

Te Papa

EYE SPY: The arrow points to the location of the eye – the biggest recorded in the animal kingdon – of the collossal squid being dissected at Te Papa. Bottom: scientists measure the thawing squid.

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The world’s most famous colossal squid was still thawing this afternoon today in a museum laboratory as researchers prepared to measure it, probe its interior, and take samples.
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But two Swedish professors specialising vision in invertebrates, Eric Warrant and Dan Nilsson, of the University of Lund, said they were rapt that the thaw has already revealed the animal kingdom’s biggest eye, 27cm across, with a lens measuring between 10cm and 12cm wide.

Below the eye was a light-emitting organ, a photophore light cell, used by some other squid species for illuminating prey, or for signalling other squid.

“This is the largest eye ever recorded in history and studied,” said Prof Warrant.

“The massive size of the eye indicates the animal is very visual.

“It has a huge lens the size of an orange and captures an awful lot of light in the dark depths in which it hunts.”

One of the eyes was too damaged to preserve, and only minimally invasive investigations would be made of the remaining one.

“They’re larger than dinner plates – they’re truly fantastic eyes,” Dr Steve O’Shea, a squid expert at Auckland’s University of Technology, who is among the scientific team of 10.

Because parts of the body were still thawing when it was shown off to media, the colossal squid’s overall length – expected to be about 8m – had not been measured.

The 495kg carcass of the Mesonychoteuthis hamiltoni specimen caught in February 2007 in the Ross Sea off Antarctica has been defrosting since Monday afternoon at the Museum of New Zealand.

The museum is showing the operation on a live webcast, which attracted 99,000 viewers yesterday.

Little is known about colossal squid and scientists were today hoping the thawing might reveal it as a male, so they could gain insights into its reproduction. One of the first tasks will be determining the creature’s gender.

“If we get ourselves a male it will be the first reported (scientific) description of the male of the species,” Dr O’Shea said.

But he said today that so far the thaw had not disclosed a large penis or special arms for transferring packets of sperm to females, which made it more likely the specimen was a female.

Dr O’Shea said an early estimate of the squid’s beak length at between 43mm and 45mm indicated it was not the biggest of its species.

“We certainly haven’t seen the largest specimen yet,” he said today. “The beak on the 495kg animal is considerably smaller than the largest beak that we have recovered from the stomach contents of sperm whales.

“Another individual may be as large as 750kg.”

Beaks found partly digested in sperm whales’ stomachs have measured up to 49mm. Beak length is related to the overall size of the squid, but scientists will need many specimens to work out the exact size relationship between the beak and body mass.

When the interior of the squid thaws, Dr O’Shea and another AUT researcher, Kat Bolstad, will investigate the colossal squid with Tsunemi Kubodera of Japan’s National Museum of Nature and Science. Their examination is being broadcast on the internet (http://www.r2.co.nz/20080427/rotate-1.asx).

The defrosted squid must be preserved in a formalin solution tonight before it starts to decay. After three or four weeks “fixing” in 7000 litres of formalin, it will be put on display in a purpose-built tank at the end of the year.