Advanced

The giant eyes of giant squid are indeed unexpectedly large, but not if used for spotting sperm whales

Nilsson, Dan-E LU ; Warrant, Eric LU ; Johnsen, Soenke; Hanlon, Roger T. and Shashar, Nadav (2013) In BMC Evolutionary Biology 13.
Abstract
Background: We recently reported (Curr Biol 22:683-688, 2012) that the eyes of giant and colossal squid can grow to three times the diameter of the eyes of any other animal, including large fishes and whales. As an explanation to this extreme absolute eye size, we developed a theory for visual performance in aquatic habitats, leading to the conclusion that the huge eyes of giant and colossal squid are uniquely suited for detection of sperm whales, which are important squid-predators in the depths where these squid live. A paper in this journal by Schmitz et al. (BMC Evol Biol 13:45, 2013) refutes our conclusions on the basis of two claims: (1) using allometric data they argue that the eyes of giant and colossal squid are not unexpectedly... (More)
Background: We recently reported (Curr Biol 22:683-688, 2012) that the eyes of giant and colossal squid can grow to three times the diameter of the eyes of any other animal, including large fishes and whales. As an explanation to this extreme absolute eye size, we developed a theory for visual performance in aquatic habitats, leading to the conclusion that the huge eyes of giant and colossal squid are uniquely suited for detection of sperm whales, which are important squid-predators in the depths where these squid live. A paper in this journal by Schmitz et al. (BMC Evol Biol 13:45, 2013) refutes our conclusions on the basis of two claims: (1) using allometric data they argue that the eyes of giant and colossal squid are not unexpectedly large for the size of the squid, and (2) a revision of the values used for modelling indicates that large eyes are not better for detection of approaching sperm whales than they are for any other task. Results and conclusions: We agree with Schmitz et al. that their revised values for intensity and abundance of planktonic bioluminescence may be more realistic, or at least more appropriately conservative, but argue that their conclusions are incorrect because they have not considered some of the main arguments put forward in our paper. We also present new modelling to demonstrate that our conclusions remain robust, even with the revised input values suggested by Schmitz et al. (Less)
Please use this url to cite or link to this publication:
author
organization
publishing date
type
Contribution to journal
publication status
published
subject
keywords
Vision, Eyes, Giant squid, Sperm whale, Bioluminescence, Mesopelagic
in
BMC Evolutionary Biology
volume
13
publisher
BioMed Central
external identifiers
  • wos:000324296700001
  • scopus:84883547732
ISSN
1471-2148
DOI
10.1186/1471-2148-13-187
language
English
LU publication?
yes
id
85779ce3-e0ba-46c2-9608-d205f0c40f7d (old id 4106547)
date added to LUP
2013-11-13 11:41:55
date last changed
2019-08-07 02:30:28
@article{85779ce3-e0ba-46c2-9608-d205f0c40f7d,
  abstract     = {Background: We recently reported (Curr Biol 22:683-688, 2012) that the eyes of giant and colossal squid can grow to three times the diameter of the eyes of any other animal, including large fishes and whales. As an explanation to this extreme absolute eye size, we developed a theory for visual performance in aquatic habitats, leading to the conclusion that the huge eyes of giant and colossal squid are uniquely suited for detection of sperm whales, which are important squid-predators in the depths where these squid live. A paper in this journal by Schmitz et al. (BMC Evol Biol 13:45, 2013) refutes our conclusions on the basis of two claims: (1) using allometric data they argue that the eyes of giant and colossal squid are not unexpectedly large for the size of the squid, and (2) a revision of the values used for modelling indicates that large eyes are not better for detection of approaching sperm whales than they are for any other task. Results and conclusions: We agree with Schmitz et al. that their revised values for intensity and abundance of planktonic bioluminescence may be more realistic, or at least more appropriately conservative, but argue that their conclusions are incorrect because they have not considered some of the main arguments put forward in our paper. We also present new modelling to demonstrate that our conclusions remain robust, even with the revised input values suggested by Schmitz et al.},
  articleno    = {187},
  author       = {Nilsson, Dan-E and Warrant, Eric and Johnsen, Soenke and Hanlon, Roger T. and Shashar, Nadav},
  issn         = {1471-2148},
  keyword      = {Vision,Eyes,Giant squid,Sperm whale,Bioluminescence,Mesopelagic},
  language     = {eng},
  publisher    = {BioMed Central},
  series       = {BMC Evolutionary Biology},
  title        = {The giant eyes of giant squid are indeed unexpectedly large, but not if used for spotting sperm whales},
  url          = {http://dx.doi.org/10.1186/1471-2148-13-187},
  volume       = {13},
  year         = {2013},
}