https://en.wikipedia.org/wiki/Yellow-bellied_toad
dv said:
https://en.wikipedia.org/wiki/Yellow-bellied_toad
Is there a known advantage?
roughbarked said:
dv said:
https://en.wikipedia.org/wiki/Yellow-bellied_toad
Is there a known advantage?
Most frogs have circular pupils when fully dilated, but when adverse conditions like strong daylight they retract, which is when some species have noticeably horizontal pupils, whilst other vertical. Apparently, the pupal shape can assist with their vision (whether daytime or night) and for measuring distance as required by jumping tree frogs to gauge how far they must jump, whilst ground dwelling species (often burrowing frogs) do not need this level of judgement. Perhaps the heart shaped pupils provide reasonable all-round vision, but not especially good or specific, although good enough for their requirements.
I’ve always liked the cuttlefish pupil myself, but this one is good too..
Arts said:
I’ve always liked the cuttlefish pupil myself, but this one is good too..
Yes it’s trippy as balls
here’s one I prepared earlier
Cymek said:
Arts said:
I’ve always liked the cuttlefish pupil myself, but this one is good too..
Yes it’s trippy as balls
Look at the frog, don’t lick it…
Witty Rejoinder said:
Cymek said:
Arts said:
I’ve always liked the cuttlefish pupil myself, but this one is good too..
Yes it’s trippy as balls
Look at the frog, don’t lick it…
Seems to e a Simpson’s theme in the forum today.
PermeateFree said:
roughbarked said:
dv said:
https://en.wikipedia.org/wiki/Yellow-bellied_toad
Is there a known advantage?
Most frogs have circular pupils when fully dilated, but when adverse conditions like strong daylight they retract, which is when some species have noticeably horizontal pupils, whilst other vertical. Apparently, the pupal shape can assist with their vision (whether daytime or night) and for measuring distance as required by jumping tree frogs to gauge how far they must jump, whilst ground dwelling species (often burrowing frogs) do not need this level of judgement. Perhaps the heart shaped pupils provide reasonable all-round vision, but not especially good or specific, although good enough for their requirements.
I can sort-of see an advantage.
Because human pupils are round, the physical muscle mass means that they can never close tightly or open widely. The tighter the closure the better the resolution. The wider the opening the better the night sight.
Vertical slit pupils don’t suffer from this problem. They can close and open more, allowing better horizontal resolution during the day and better vision at night. The disadvantage is that they have poor vertical resolution at all times. So it’s a trade off between better night sight and poor vertical resolution.
For a cuttlefish pupil, the best resolution would be in the direction that the pupil is facing. Being c—shape lying on its back this would mean better horizontal resolution fore and aft and directly below. With very little vision directly above.
For a heart-shaped frog pupil, it’s complicated. But there are directions in which vision is better and directions in which vision is worse. And implications for night sight.
