By day, mantis eyes are green (or some other camouflage color) because light is reflected away from pigment cells that surround each facet of the eye. Light can only enter their eye facets by going straight down a narrow tunnel, and this tight control of light entering the eyes gives them better visual acuity. An effect of all this is the 'pseudopupil' -- the dark spot on each compound eye where the viewer is looking straight down the small group of eye facets that happen to be aimed right at the viewer. This is why this hungry lady seems to be looking at you.
At night, mantises adapt their eyes for night vision by moving the reflective pigment cells away from the surface of the compound eyes. This allows in more light for 'night vision', but it also makes them look like bug-eyed aliens.
Preying mantis eyes during the day, and during the night
Moderators: rjlittlefield, ChrisR, Chris S., Pau
- MarkSturtevant
- Posts: 1946
- Joined: Sat Nov 21, 2015 6:52 pm
- Location: Michigan, U.S.A.
- Contact:
Preying mantis eyes during the day, and during the night
Mark Sturtevant
Dept. of Still Waters
Dept. of Still Waters
- rjlittlefield
- Site Admin
- Posts: 23564
- Joined: Tue Aug 01, 2006 8:34 am
- Location: Richland, Washington State, USA
- Contact:
Mark, excellent photographs!
I've observed this effect before and found it very interesting, as documented at http://www.photomacrography.net/forum/v ... php?t=3074 .
So now I am again curious: do all mantis do this?
--Rik
I've observed this effect before and found it very interesting, as documented at http://www.photomacrography.net/forum/v ... php?t=3074 .
So now I am again curious: do all mantis do this?
--Rik
I did some research work on moths (nocturnal) at UK Uni. Different species of moths came to a light trap at different times of night and are active for different periods. This was not known previously.
That inferred to my supervisor different diurnal rhythms. But there is always the possibility (I said) that very small variations in lux over the night (there are these even with a cloudless night - tested) might also have an influence on the diurnal rhythms or physical changes in the ommatidia.
Other previous research had shown physical evidence in certain species of moth that the pigment migrated in the ommatidia for light and dark adapted.
The suggestion was that in light adapted mode moths would be inactive.
I did not get further funding so the question is still open.
Regards
John
That inferred to my supervisor different diurnal rhythms. But there is always the possibility (I said) that very small variations in lux over the night (there are these even with a cloudless night - tested) might also have an influence on the diurnal rhythms or physical changes in the ommatidia.
Other previous research had shown physical evidence in certain species of moth that the pigment migrated in the ommatidia for light and dark adapted.
The suggestion was that in light adapted mode moths would be inactive.
I did not get further funding so the question is still open.
Regards
John
- MarkSturtevant
- Posts: 1946
- Joined: Sat Nov 21, 2015 6:52 pm
- Location: Michigan, U.S.A.
- Contact:
I don't know. I can only add that the color change happens on schedule even when they are in captivity & kept in a well lit room. So to me that means it is a circadian cycle rather than being induced by light or dark.rjlittlefield wrote: So now I am again curious: do all mantis do this?
--Rik
Mark Sturtevant
Dept. of Still Waters
Dept. of Still Waters
- rjlittlefield
- Site Admin
- Posts: 23564
- Joined: Tue Aug 01, 2006 8:34 am
- Location: Richland, Washington State, USA
- Contact:
Very interesting! I did not notice that with my subject. I have vague memories that I tried putting the beast in a dark closet in the middle of the day and saw at least partial darkening then. But the memories could be wrong, and I do not have notes to check. Perhaps another mantis will turn up this next summer so I can look specifically for that effect.MarkSturtevant wrote:I can only add that the color change happens on schedule even when they are in captivity & kept in a well lit room. So to me that means it is a circadian cycle rather than being induced by light or dark.
--Rik
- MarkSturtevant
- Posts: 1946
- Joined: Sat Nov 21, 2015 6:52 pm
- Location: Michigan, U.S.A.
- Contact:
I know a few people who had encountered this phenomenon when they find a well-fed mantis in the morning at their porch light or window, where it had spent the night feeding on insects. The eyes are still dark early in the morning.Lou Jost wrote:Mark, that's a fascinating observation! Probably common across many insect groups. It is the kind of thing no one would notice except for someone like you who raises insects and observes them closely. It shows how ignorant most of us are about even the most common things on this planet.
Mark Sturtevant
Dept. of Still Waters
Dept. of Still Waters