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The sea urchin Diadema africanum uses low resolution vision to find shelter and deter enemies

Research output: Contribution to journalArticle

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The sea urchin Diadema africanum uses low resolution vision to find shelter and deter enemies. / Kirwan, John D.; Bok, Michael J.; Smolka, Jochen; Foster, James J.; Hernández, José Carlos; Nilsson, Dan Eric.

In: Journal of Experimental Biology, Vol. 221, No. 14, jeb176271, 07.2018.

Research output: Contribution to journalArticle

Harvard

Kirwan, JD, Bok, MJ, Smolka, J, Foster, JJ, Hernández, JC & Nilsson, DE 2018, 'The sea urchin Diadema africanum uses low resolution vision to find shelter and deter enemies', Journal of Experimental Biology, vol. 221, no. 14, jeb176271. https://doi.org/10.1242/jeb.176271

APA

Kirwan, J. D., Bok, M. J., Smolka, J., Foster, J. J., Hernández, J. C., & Nilsson, D. E. (2018). The sea urchin Diadema africanum uses low resolution vision to find shelter and deter enemies. Journal of Experimental Biology, 221(14), [jeb176271]. https://doi.org/10.1242/jeb.176271

Vancouver

Kirwan JD, Bok MJ, Smolka J, Foster JJ, Hernández JC, Nilsson DE. The sea urchin Diadema africanum uses low resolution vision to find shelter and deter enemies. Journal of Experimental Biology. 2018 Jul;221(14). jeb176271. https://doi.org/10.1242/jeb.176271

Author

Kirwan, John D. ; Bok, Michael J. ; Smolka, Jochen ; Foster, James J. ; Hernández, José Carlos ; Nilsson, Dan Eric. / The sea urchin Diadema africanum uses low resolution vision to find shelter and deter enemies. In: Journal of Experimental Biology. 2018 ; Vol. 221, No. 14.

Bibtex

@article{2a3beb4815bf40948bd630937e742eff,
title = "The sea urchin Diadema africanum uses low resolution vision to find shelter and deter enemies",
abstract = "Many sea urchins can detect light on their body surface and some species are reported to possess image-resolving vision. Here, we measure the spatial resolution of vision in the long-spined sea urchin Diadema africanum, using two different visual responses: a taxis towards dark objects and an alarm response of spine-pointing towards looming stimuli. For the taxis response we used visual stimuli, which were isoluminant to the background, to discriminate spatial vision from phototaxis. Individual animals were placed in the centre of a cylindrical arena under bright down-welling light, with stimuli of varying angular width placed on the arena wall at alternating directions from the centre. We tracked the direction of movement of individual animals in relation to the stimuli to determine whether the animals oriented towards the stimulus. We found that D. africanum responds by taxis towards isoluminant stimuli with a spatial resolution in the range of 29–69 deg. This corresponds to a theoretical acceptance angle of 38–89 deg, assuming a contrast threshold of 10{\%}. The visual acuity of the alarm response of D. africanum was tested by exposing animals to different sized dark looming and appearing stimuli on a monitor. We found that D. africanum displays a spine-pointing response to appearing black circles of 13–25 deg angular width, corresponding to an acceptance angle of 60–116 deg, assuming the same contrast threshold as above.",
keywords = "Echinoidea, Photoreception, Sea urchin, Visual acuity, Visual response, Visually guided behaviour",
author = "Kirwan, {John D.} and Bok, {Michael J.} and Jochen Smolka and Foster, {James J.} and Hern{\'a}ndez, {Jos{\'e} Carlos} and Nilsson, {Dan Eric}",
note = "{\circledC} 2018. Published by The Company of Biologists Ltd.",
year = "2018",
month = "7",
doi = "10.1242/jeb.176271",
language = "English",
volume = "221",
journal = "Journal of Experimental Biology",
issn = "0022-0949",
publisher = "Company of Biologists Ltd",
number = "14",

}

RIS - suitable for import to EndNote

TY - JOUR

T1 - The sea urchin Diadema africanum uses low resolution vision to find shelter and deter enemies

AU - Kirwan, John D.

AU - Bok, Michael J.

AU - Smolka, Jochen

AU - Foster, James J.

AU - Hernández, José Carlos

AU - Nilsson, Dan Eric

N1 - © 2018. Published by The Company of Biologists Ltd.

PY - 2018/7

Y1 - 2018/7

N2 - Many sea urchins can detect light on their body surface and some species are reported to possess image-resolving vision. Here, we measure the spatial resolution of vision in the long-spined sea urchin Diadema africanum, using two different visual responses: a taxis towards dark objects and an alarm response of spine-pointing towards looming stimuli. For the taxis response we used visual stimuli, which were isoluminant to the background, to discriminate spatial vision from phototaxis. Individual animals were placed in the centre of a cylindrical arena under bright down-welling light, with stimuli of varying angular width placed on the arena wall at alternating directions from the centre. We tracked the direction of movement of individual animals in relation to the stimuli to determine whether the animals oriented towards the stimulus. We found that D. africanum responds by taxis towards isoluminant stimuli with a spatial resolution in the range of 29–69 deg. This corresponds to a theoretical acceptance angle of 38–89 deg, assuming a contrast threshold of 10%. The visual acuity of the alarm response of D. africanum was tested by exposing animals to different sized dark looming and appearing stimuli on a monitor. We found that D. africanum displays a spine-pointing response to appearing black circles of 13–25 deg angular width, corresponding to an acceptance angle of 60–116 deg, assuming the same contrast threshold as above.

AB - Many sea urchins can detect light on their body surface and some species are reported to possess image-resolving vision. Here, we measure the spatial resolution of vision in the long-spined sea urchin Diadema africanum, using two different visual responses: a taxis towards dark objects and an alarm response of spine-pointing towards looming stimuli. For the taxis response we used visual stimuli, which were isoluminant to the background, to discriminate spatial vision from phototaxis. Individual animals were placed in the centre of a cylindrical arena under bright down-welling light, with stimuli of varying angular width placed on the arena wall at alternating directions from the centre. We tracked the direction of movement of individual animals in relation to the stimuli to determine whether the animals oriented towards the stimulus. We found that D. africanum responds by taxis towards isoluminant stimuli with a spatial resolution in the range of 29–69 deg. This corresponds to a theoretical acceptance angle of 38–89 deg, assuming a contrast threshold of 10%. The visual acuity of the alarm response of D. africanum was tested by exposing animals to different sized dark looming and appearing stimuli on a monitor. We found that D. africanum displays a spine-pointing response to appearing black circles of 13–25 deg angular width, corresponding to an acceptance angle of 60–116 deg, assuming the same contrast threshold as above.

KW - Echinoidea

KW - Photoreception

KW - Sea urchin

KW - Visual acuity

KW - Visual response

KW - Visually guided behaviour

UR - http://www.scopus.com/inward/record.url?scp=85050333215&partnerID=8YFLogxK

U2 - 10.1242/jeb.176271

DO - 10.1242/jeb.176271

M3 - Article

C2 - 29739834

VL - 221

JO - Journal of Experimental Biology

JF - Journal of Experimental Biology

SN - 0022-0949

IS - 14

M1 - jeb176271

ER -