Feeds

Mega squid use HUMONGOUS eyes to spot ravenous sperm whales

Boffins float theory on colossal creatures' eyesight

Beginner's guide to SSL certificates

Ocean-researching boffins reckon they have figured out why giant and colossal deep sea-dwelling squid need the largest eyes in the animal kingdom: to spot huge predators like sperm whales.

Fresh head of a giant squid caught in 1981

Fresh head of a giant squid caught in 1981 by fisherman Henry Olsen.

Picture by Ernie Choy at the pier, reproduced in the study.

The gargantuan many-legged creatures can have eyes the size of basketballs, which has puzzled many marine biologists.

"It doesn't make sense. A giant squid and swordfish are similar in size but the squid's eyes are proportionally much larger, three times the diameter and 27 times the volume," Duke University biologist Dr Sonke Johnsen said in a statement. "The question is why. Why do giant squid need such large eyes?"

Johnsen and the other marine experts in the study have found that the size and design of the squid's eyes could be used for spotting whales approaching from up to 120m away at depths below 600m.

The researchers first measured giant and colossal squid eyes using photos and captured animals, which was not as easy as it sounds because once the immense cephalopods die, their eyes become distorted.

Putting this together with data about the water clarity and quantity of light at the ocean depth where the humungous squid live, the boffins theorise that their eyes collect more light than other giant animals with smaller optical orbs.

This extra light-gathering ability allows the sea-creatures to spot faint bioluminescence from metres away. That bioluminescence is given off by plankton when they're disturbed by a whale's sonar, alerting the monstrous squids to the approach of something big enough to chow down on them.

The keen eyesight is of particular importance because the giant squids are deaf to the sonar that whales produce.

"It's the predation by large, toothed whales that has driven the evolution of gigantism in the eyes of these squid," Johnsen said.

Johnsen et al also think that the theory could provide insight into the vision of the Mesozoic ichthyosaurs, a type of swimming reptile that had unusually large eyeballs.

However, the paper, published in the journal Current Biology, is still a hypothesis.

"I like the idea. The paper is speculative, however," said Michael Land, a University of Sussex zoologist who was not involved in the study. "Big eyes are always better, and the laws of growth that tend to make large vertebrates have relatively smaller eyes may not apply to cephalopods. Maybe they just grow that big."

The boffin team plans to publish a compete theory on underwater vision later this year. ®

Secure remote control for conventional and virtual desktops

More from The Register

next story
Antarctic ice THICKER than first feared – penguin-bot boffins
Robo-sub scans freezing waters, rocks warming models
Your PHONE is slowly KILLING YOU
Doctors find new Digitillnesses - 'text neck' and 'telepressure'
SEX BEAST SEALS may be egging each other on to ATTACK PENGUINS
Boffin: 'I think the behaviour is increasing in frequency'
Reuse the Force, Luke: SpaceX's Elon Musk reveals X-WING designs
And a floating carrier for recyclable rockets
The next big thing in medical science: POO TRANSPLANTS
Your brother's gonna die, kid, unless we can give him your, well ...
NASA launches new climate model at SC14
75 days of supercomputing later ...
Britain's HUMAN DNA-strewing Moon mission rakes in £200k
3 days, and Kickstarter moves lander 37% nearer takeoff
prev story

Whitepapers

Seattle children’s accelerates Citrix login times by 500% with cross-tier insight
Seattle Children’s is a leading research hospital with a large and growing Citrix XenDesktop deployment. See how they used ExtraHop to accelerate launch times.
Why CIOs should rethink endpoint data protection in the age of mobility
Assessing trends in data protection, specifically with respect to mobile devices, BYOD, and remote employees.
A strategic approach to identity relationship management
ForgeRock commissioned Forrester to evaluate companies’ IAM practices and requirements when it comes to customer-facing scenarios versus employee-facing ones.
High Performance for All
While HPC is not new, it has traditionally been seen as a specialist area – is it now geared up to meet more mainstream requirements?
Protecting against web application threats using SSL
SSL encryption can protect server‐to‐server communications, client devices, cloud resources, and other endpoints in order to help prevent the risk of data loss and losing customer trust.