How does the northern leopard frog see?
The northern leopard frog (Lithobates pipiens) is a amphibian in the order Anura. Its eyes belong to the vision type Amphibian motion detector: low acuity, dim-light specialists (two rod types), strongest response to moving objects.
Measured in this species: colour, sharpness and night vision. Measured core: measured values on at least 3 of the 6 dials. Every value below carries its evidence level and sources; nothing is typed by hand.


What stands out
- It has two colour receptor classes (a dichromat): reds and greens fall on one axis, as in red-green colour blindness in people.
- Its sharpest vision resolves 2.8 cycles per degree: the finest stripe pattern it can tell apart from grey.
- It stops seeing flicker at 21 Hz, against 60 Hz for people in this dataset, so fast motion looks choppier to it.[10][9]
- Activity pattern: cathemeral.
The six dials
Evidence levels: how the tiers work. "Measured" means a value measured in this species; "Estimated" values come from a close relative or an eye-size formula.
| Dial | Value | Evidence | Sources |
|---|---|---|---|
| Colour | Colour receptors 2 receptor classes: 502 nm (MWS (green)), 562 nm (LWS (long)) measured in this species | Measured (not re-verified) | [1][2] |
| Sharpness | Acuity 2.8 cycles per degree median of 1 behavioural rows (method priority rule) | Measured | [3] |
| Field of view | No value in the catalogue. | ||
| Sharp zones (foveas) | No value in the catalogue. | ||
| Night vision | Activity pattern cathemeral mode of 5 rows (of 5 rows): arrhythmic/cathemeral; cathemeral; diurnal and nocturnal; nocturnal | Measured (not re-verified) | [4][2][5][6][7] |
| Pupil shape horizontal | Measured | [8] | |
| Rods vs cones mixed nocturnal -> rod-dominated; crepuscular / cathemeral / mixed -> mixed; diurnal -> cone-dominated | Derived | [4][2][5][6][7] | |
| Motion (flicker fusion) | Flicker fusion frequency 21 Hz median of 1 relatives in genus Lithobates: Lithobates clamitans | Estimated | [9] |
Related animals
- African clawed frog same vision type
- American bullfrog same vision type
- Asiatic toad same vision type
- Bufo toad same vision type
- Common frog same vision type
- Common toad same vision type
More amphibians: all amphibians with measured vision data.
Sources
- Yovanovich CAM, Koskela SM, Nevala N, Kondrashev SL, Kelber A, Donner K. 2017. The dual rod system of amphibians supports colour discrimination at the absolute visual threshold. Phil Trans R Soc B 372:20160066.. doi.org/10.1098/rstb.2016.0066
- Longcore T. 2023. A compendium of photopigment peak sensitivities and visual spectral response curves of terrestrial wildlife to guide design of outdoor nighttime lighting. Basic Appl Ecol 73:40-50. doi:10.1016/j.baae.2023.09.002. doi.org/10.5281/zenodo.8432720
- Caves EM, Fernandez-Juricic E, Kelley LA (2024) Ecological and morphological correlates of visual acuity in birds. J Exp Biol 227(2): jeb246063. Supplementary Table S1.. doi.org/10.1242/jeb.246063
- Anderson SR, Wiens JJ. 2017. Out of the dark: 350 million years of conservatism and evolution in diel activity patterns in vertebrates. Evolution 71:1944-1959. Dryad doi:10.5061/dryad.fg700. doi.org/10.5061/dryad.fg700
- Schott RK, Fujita MK, Streicher JW, Gower DJ, Thomas KN, Loew ER, et al. (28 authors, last Bell RC). 2024. Diversity and evolution of frog visual opsins: spectral tuning and adaptation to distinct light environments. Mol Biol Evol 41:msae049.. doi.org/10.1093/molbev/msae049
- Moura et al. 2024. A phylogeny-informed characterisation of global tetrapod traits addresses data gaps and biases. PLoS Biol 22:e3002658. TetrapodTraits v3.0.1.. doi.org/10.5281/zenodo.22536349
- Wan YC, Navarrete Mendez MJ, O'Connell LA, Uricchio LH, Roland AB, Maan ME, Ron SR, Betancourth-Cundar M, Pie MR, Howell KA, Richards-Zawacki CL, Cummings ME, Cannatella DC, Santos JC, Tarvin RD. 2023. Selection on visual opsin genes in diurnal Neotropical frogs and loss of the SWS2 opsin in poison frogs. Mol Biol Evol 40:msad206.. doi.org/10.1093/molbev/msad206
- Cervino NG et al. 2021. A closer look at pupil diversity and evolution in frogs and toads. Proc R Soc B 288:20211402. doi.org/10.6084/m9.figshare.15112050.v1
- Inger R, Bennie J, Davies TW, Gaston KJ. 2014. Potential biological and ecological effects of flickering artificial light. PLoS ONE 9(5): e98631. Table 3. doi.org/10.1371/journal.pone.0098631
- Healy K, McNally L, Ruxton GD, Cooper N, Jackson AL. 2013. Metabolic rate and body size are linked with perception of temporal information. Animal Behaviour 86:685-696. Table 1. doi.org/10.1016/j.anbehav.2013.06.018
Every value cites its sources (all sources). Data: catalogue-v1, built 2026-09-29. Accuracy notes: how accurate is this?