How stomatopods judge distance

Gonodactylus · 01/14/2008, 06:35 PM

Ever wonder how how a stomatopd knows how far away an object is that it is trying to spear? This image of a juvenile Lysiosquillina sulcata looking out of its burrow provides some of the answers. Each eye is made up of hundreds of indivdiual optical units called ommatidia. Each ommatidium is like a telescope looking out at a small piece of the world. When light enters an ommatidium "on axis" (straight down the barrel), the light is absorbed and is not reflected back. The ommatidium appears black. This is analogous to looking into the pupil of a human eye, No light is being reflected back and the pupil appears black. Hence, we call these black spots on the surface of a stomatopod eye "pseudopupils".

The pattern of pseudopupils in a stomatopod eye can tell us where the various ommatida are aimed. When I took this picture, the eye on the left was pointed in the direction of the camera lens. You can see a cluster of dark spots in the center of the upper and lower hemispheres of the eye as well as another group of dark spots in the center. This means that some of the ommatidia in the mid-band of the eye as well as as groups in the upper and lower part of the eye are pointing right at the camera.

The eye on the right is looking to the right. Only a few ommatidia on the extreme periphery are pointing towards the camera. Notice that the surface of the eye near the center is concave. The ommatidia (in spearers) generally point outward perpendicular to the surface. That means that objects located directly in front, but close to the eye will be seen by ommatidia close to the midband; objects further away but in the same direction will be seen by ommatidia further from the midband. Alternatively, if I moved my camera closer to the eye, the pseudopupils would be seen closer the the midband. The ommatida of the midband (made up of six rows of ommatidia) all look out on the same equatorial plane.

Just as you tell how far objects are away by using binocular vision analyzing how much your eyes are pointing toward the mid-line, the stomatopod can judge distanceby comparing which ommatidia are focused on the same spot. The difference is that when the stomatopod is looking intently at an object using both eyes, it has six regions of the eyes brought to bare on the target giving it hexnocular vision.

Roy

lifemalfunction · 01/14/2008, 08:20 PM

Awesome write up, Roy. I often wondered how they judged distance and how their eyes worked in general. I had noticed the Ommitidia before, but had no idea what they are.

Very interesting.

Feclar · 01/14/2008, 11:40 PM

excellent read!

Thank you for the all the info you provide, always look forward to it

jdieck · 01/15/2008, 12:04 AM

justinl · 01/15/2008, 12:29 AM

that is a gorgeous eye ball shot! amazing detail. I love reading these stomato-info-posts of yours. I learn something new in every single one.

Agu · 01/15/2008, 10:20 PM

Hope you don't mind that I stuck this.

JokerGirl · 01/18/2008, 06:17 AM

Very interesting read Dr. Roy. Thanks so much for posting this as I've wondered for a while how their eyes actually work.

Altpers0na · 01/18/2008, 11:48 AM

im glad you stuck this.

MTV · 01/23/2008, 04:40 PM

Thanks for this Dr Roy, this explains their vision in a much simpler way than in other places I've read. Very interesting!

Grym · 05/21/2008, 09:19 PM

I'm new to the forum but I had a mantis show up 10 years ago after 10 fish disappeared one by one over a month. I had to remove all the live rock to get him out of the tank. Got interested in them after that and read a lot. I believe I have read that the mantis shrimp has 21, and later in another read 23 types of sensors in their eyes. Like we have rods to see black and white and cones to see color the mantis have at least 21 types in their eyes. They see way into the infrared and ultraviolet and who knows what else. I also believe they use these to identify their mates in the deep darkness. Am I remembering that all right?
Len

Gonodactylus · 05/21/2008, 11:50 PM

Len,

There are up to 16 visual pigments that respond from 300 to 700 nm. That is not into the infrared, but it is the broadest spectral sensivity of any known animal.

Roy

hidnReefAquatic · 03/07/2009, 10:56 AM

stardrop · 05/03/2009, 03:40 PM

Would you mind posting the picture again? The link appears to be broken.

Gonodactylus · 05/04/2009, 10:50 AM

O.K., it's fixed. Don't know what happened.

Roy

wschang812 · 06/25/2009, 10:39 PM

heard they have the most complex eyes in the animal kingdom

Thurge · 08/23/2009, 10:35 AM

Quote:

Originally posted by Gonodactylus
Len,

There are up to 16 visual pigments that respond from 300 to 700 nm. That is not into the infrared, but it is the broadest spectral sensivity of any known animal.

Roy

Does that mean that where the human eye sees the three primary colors Red, Blue and Green, and makes all the other colors we see from the combination of these three colors, that Mantis shrimp see in 16 "primary colors"?

Thanks
David

Gonodactylus · 08/23/2009, 11:03 AM

Basically, correct including 4 in the uv (300-400 nm). This probably allows for much more color constancy.

Roy

JoeCreature · 09/11/2009, 12:21 PM

Roy, do you think they could detect the changes in UV radiation striking the Earth as the sunspot cycle changes the blackbody radiation? I.e. Do you think they can tell it is "brighter"?

Gonodactylus · 09/11/2009, 12:35 PM

If it were an instantaneous change from minimum to maximum, perhaps, but not if the change is gradual over even minutes let alone years.

Roy

Koshmar · 09/11/2009, 01:59 PM

Dr. Roy, what would be the average distance a stomatopod could see outside its tank? I'm just looking for a general answer, say the thickness of a ten gallon glass tank with clean glass out and inside. I always wonder if my stomatopods can see me before I enter the room.
What about in the ocean?

Thurge · 09/13/2009, 10:25 AM

If called to testify I would say that my G>chiagra could see all the way into another room. Not only that but he would do it using the glass as mirrors. I can't count the number of times I found him in his burrow facing out but with his eyes turned to the side as if he had been watching a reflection of the family in the kitchen.

voigtstr · 09/23/2009, 07:43 AM

For anyone that has seen the movie "Watchmen" do people think that mantis' eyes look like Rorschach's mask?

Aqua_boy · 12/23/2009, 06:51 AM

Very interesting.........

brako · 02/04/2010, 07:06 AM

they look like a pair of slippers lol

NanoReefWanabe · 01/24/2011, 08:13 PM

Quote:

Originally Posted by Thurge

Does that mean that where the human eye sees the three primary colors Red, Blue and Green, and makes all the other colors we see from the combination of these three colors, that Mantis shrimp see in 16 "primary colors"?

Thanks
David

not to get off topic but the three primary colours are red blue and yellow not green..

the eye of this animal is fascinating...i was just at Aquatic Kingdom in Mississauga and they had 2 5" peacock mantis' and i stood there and watched them for about an hour, very interesting and inquisitive animal...i would have to say they can certainly see out of the tank...cause both of these two where intently watching the tanks beside them full of cleaner shrimp and sally light foots and snails...it almost looked as though they were licking their chops..LOL

01/14/2008, 06:35 PM	#1
Gonodactylus Premium Member Join Date: Aug 2001 Location: Berkeley, CA, USA Posts: 5,024	How stomatopods judge distance Ever wonder how how a stomatopd knows how far away an object is that it is trying to spear? This image of a juvenile Lysiosquillina sulcata looking out of its burrow provides some of the answers. Each eye is made up of hundreds of indivdiual optical units called ommatidia. Each ommatidium is like a telescope looking out at a small piece of the world. When light enters an ommatidium "on axis" (straight down the barrel), the light is absorbed and is not reflected back. The ommatidium appears black. This is analogous to looking into the pupil of a human eye, No light is being reflected back and the pupil appears black. Hence, we call these black spots on the surface of a stomatopod eye "pseudopupils". The pattern of pseudopupils in a stomatopod eye can tell us where the various ommatida are aimed. When I took this picture, the eye on the left was pointed in the direction of the camera lens. You can see a cluster of dark spots in the center of the upper and lower hemispheres of the eye as well as another group of dark spots in the center. This means that some of the ommatidia in the mid-band of the eye as well as as groups in the upper and lower part of the eye are pointing right at the camera. The eye on the right is looking to the right. Only a few ommatidia on the extreme periphery are pointing towards the camera. Notice that the surface of the eye near the center is concave. The ommatidia (in spearers) generally point outward perpendicular to the surface. That means that objects located directly in front, but close to the eye will be seen by ommatidia close to the midband; objects further away but in the same direction will be seen by ommatidia further from the midband. Alternatively, if I moved my camera closer to the eye, the pseudopupils would be seen closer the the midband. The ommatida of the midband (made up of six rows of ommatidia) all look out on the same equatorial plane. Just as you tell how far objects are away by using binocular vision analyzing how much your eyes are pointing toward the mid-line, the stomatopod can judge distanceby comparing which ommatidia are focused on the same spot. The difference is that when the stomatopod is looking intently at an object using both eyes, it has six regions of the eyes brought to bare on the target giving it hexnocular vision. Roy

01/15/2008, 12:04 AM	#4
jdieck Registered Member Join Date: Dec 2002 Location: Maumee, OH Posts: 15,673	__________________ Did I write what I wrote? What the heck am I talking about! Well..... Nevermind. Current Tank Info: 225 gal reef, DSB, 40 g sump w/ LRT100 return, 37 g pre-sump, 3 MH 250 W 15K, 4 96 W PC dual actinic,ETS 1500 Skim.w/LRT70, 20 lb Ca R., 40 W UV, 1/3 HP chiller, two 350 W Htrs, Neptune II Cont., 330 P LR/ 330 P LS. 55 gal Refugium

01/15/2008, 10:20 PM	#6
Agu Registered Member Join Date: Oct 1999 Location: Sarasota, Florida Posts: 30,279	Hope you don't mind that I stuck this. __________________ Less technology , more biology . Current Tank Info: 30 gallon half cube and 5.5, both reef tanks

01/18/2008, 06:17 AM	#7
JokerGirl Whistler's Mother Join Date: Nov 2006 Location: That place Posts: 1,345	Very interesting read Dr. Roy. Thanks so much for posting this as I've wondered for a while how their eyes actually work. __________________ 01000001 01101110 01111001 01101111 01101110 01100101 00111111 Current Tank Info: 120g Reef Tank, 60g Cube Mantis/Reef Tank, Want more info, ask me.

01/18/2008, 11:48 AM	#8
Altpers0na ARS Caesar Join Date: Feb 2006 Location: Western PA Posts: 1,235	im glad you stuck this. __________________ We are not descended from fearful men. The Final Countdown is now stuck in your head. I use "..." excessively Current Tank Info: tankless

01/14/2008, 08:20 PM	#2
lifemalfunction Registered Member Join Date: Aug 2007 Location: Bellingham, WA Posts: 41	Awesome write up, Roy. I often wondered how they judged distance and how their eyes worked in general. I had noticed the Ommitidia before, but had no idea what they are. Very interesting.

01/14/2008, 11:40 PM	#3
Feclar Premium Member Join Date: Dec 2007 Location: Reno, NV Posts: 170	excellent read! Thank you for the all the info you provide, always look forward to it

01/15/2008, 12:29 AM	#5
justinl Registered Member Join Date: Jan 2007 Posts: 2,118	that is a gorgeous eye ball shot! amazing detail. I love reading these stomato-info-posts of yours. I learn something new in every single one.

01/23/2008, 04:40 PM	#9
MTV Registered Member Join Date: Nov 2007 Location: Sydney, Australia Posts: 19	Thanks for this Dr Roy, this explains their vision in a much simpler way than in other places I've read. Very interesting!

05/21/2008, 09:19 PM	#10
Grym Registered Member Join Date: May 2008 Posts: 34	I'm new to the forum but I had a mantis show up 10 years ago after 10 fish disappeared one by one over a month. I had to remove all the live rock to get him out of the tank. Got interested in them after that and read a lot. I believe I have read that the mantis shrimp has 21, and later in another read 23 types of sensors in their eyes. Like we have rods to see black and white and cones to see color the mantis have at least 21 types in their eyes. They see way into the infrared and ultraviolet and who knows what else. I also believe they use these to identify their mates in the deep darkness. Am I remembering that all right? Len

05/21/2008, 11:50 PM	#11
Gonodactylus Premium Member Join Date: Aug 2001 Location: Berkeley, CA, USA Posts: 5,024	Len, There are up to 16 visual pigments that respond from 300 to 700 nm. That is not into the infrared, but it is the broadest spectral sensivity of any known animal. Roy

03/07/2009, 10:56 AM	#12
hidnReefAquatic Registered Member. Join Date: Feb 2008 Location: Peoria,IL Posts: 60

05/03/2009, 03:40 PM	#13
stardrop Registered Member Join Date: Dec 2008 Location: Ottawa, On Posts: 22	Would you mind posting the picture again? The link appears to be broken.

05/04/2009, 10:50 AM	#14
Gonodactylus Premium Member Join Date: Aug 2001 Location: Berkeley, CA, USA Posts: 5,024	O.K., it's fixed. Don't know what happened. Roy

06/25/2009, 10:39 PM	#15
wschang812 Registered Member Join Date: Jan 2009 Location: great neck, ny Posts: 64	heard they have the most complex eyes in the animal kingdom

08/23/2009, 11:03 AM	#17
Gonodactylus Premium Member Join Date: Aug 2001 Location: Berkeley, CA, USA Posts: 5,024	Basically, correct including 4 in the uv (300-400 nm). This probably allows for much more color constancy. Roy

09/11/2009, 12:21 PM	#18
JoeCreature Registered Member Join Date: Sep 2009 Location: Wilmington NC Posts: 58	Roy, do you think they could detect the changes in UV radiation striking the Earth as the sunspot cycle changes the blackbody radiation? I.e. Do you think they can tell it is "brighter"?

09/11/2009, 12:35 PM	#19
Gonodactylus Premium Member Join Date: Aug 2001 Location: Berkeley, CA, USA Posts: 5,024	If it were an instantaneous change from minimum to maximum, perhaps, but not if the change is gradual over even minutes let alone years. Roy

09/11/2009, 01:59 PM	#20
Koshmar The Hardy Mongolian Pony Join Date: Nov 2008 Location: Dallas, Texas Posts: 1,372	Dr. Roy, what would be the average distance a stomatopod could see outside its tank? I'm just looking for a general answer, say the thickness of a ten gallon glass tank with clean glass out and inside. I always wonder if my stomatopods can see me before I enter the room. What about in the ocean? __________________ All Day I Dream About Stomatopods

09/13/2009, 10:25 AM	#21
Thurge Registered Member Join Date: Jun 2003 Location: Colorado Springs Posts: 2,707	If called to testify I would say that my G>chiagra could see all the way into another room. Not only that but he would do it using the glass as mirrors. I can't count the number of times I found him in his burrow facing out but with his eyes turned to the side as if he had been watching a reflection of the family in the kitchen. __________________ What have you done with my Illudium Q-36 Explosive Space Modulator Earthling? The memories of a man in his old age, Are the deeds of a man in his prime. Pink Floyd

09/23/2009, 07:43 AM	#22
voigtstr Registered Member Join Date: Oct 2003 Location: Hobart Australia Posts: 6	For anyone that has seen the movie "Watchmen" do people think that mantis' eyes look like Rorschach's mask?

12/23/2009, 06:51 AM	#23
Aqua_boy Registered Member Join Date: Nov 2009 Location: New York Posts: 85	Very interesting.........

02/04/2010, 07:06 AM	#24
brako Registered Member Join Date: Jan 2010 Location: walsall Posts: 17	they look like a pair of slippers lol