How does the African harrier-hawk see?
The African harrier-hawk (Polyboroides typus) is a bird in the order Accipitriformes. Its eyes belong to the vision type Raptor telephoto.
Measured in this species: field of view and night vision. One measured dial: a value other than colour or sharpness is measured in this species; colour and sharpness are not measured here. Every value below carries its evidence level and sources; nothing is typed by hand.
See your photo as the African harrier-hawkThis species is part of the full catalogue in the tool (full unlock). Your photo stays on your device.
What stands out
- It has 4 colour receptor classes; people have 3.
- Its sharpest vision resolves 84 cycles per degree: the finest stripe pattern it can tell apart from grey.
- Its eyes cover about 277.5° around the head, with 27° seen by both eyes at once.
- It stops seeing flicker at 77.7 Hz, against 60 Hz for people in this dataset, so fast motion looks about 1.3 times slower to it.[13][14]
- Activity pattern: diurnal.
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 4 receptor classes: 405 nm (VS/SWS (violet)), 449 nm (SWS (blue)), 504 nm (MWS (green)), 567 nm (LWS (long)) receptor set of nearest measured relative Buteo buteo (same family Accipitridae) | Estimated | [1][2] |
| Sharpness | Acuity 84 cycles per degree median of 8 relatives in family Accipitridae: Aquila audax, Buteo jamaicensis, Gyps fulvus, Gyps indicus, Milvus migrans, Neophron percnopterus | Estimated | [3][4][5] |
| Field of view | Binocular overlap 27° median of 1 rows (eyes-at-rest rows preferred) | Measured (not re-verified) | [6] |
| Total field of view 277.5° median total field (measured, or 360 - blind area) of relatives in family Accipitridae: Accipiter cooperii, Buteo jamaicensis, Circaetus gallicus, Parabuteo unicinctus | Estimated | [7] | |
| Sharp zones (foveas) | Number of foveas 2 median of 14 relatives in family Accipitridae: Gypohierax angolensis, Neophron percnopterus, Circaetus gallicus, Gyps fulvus, Necrosyrtes monachus, Aquila chrysaetos | Estimated | [8] |
| Fovea type deep central + shallow temporal | Estimated | [8] | |
| Night vision | Activity pattern diurnal mode of 3 rows (of 3 rows): diurnal; not_nocturnal | Measured (not re-verified) | [9][10][11] |
| Rods vs cones cone-dominated nocturnal -> rod-dominated; crepuscular / cathemeral / mixed -> mixed; diurnal -> cone-dominated | Derived | [9][10][11] | |
| Motion (flicker fusion) | Flicker fusion frequency 77.7 Hz median of 1 relatives in family Accipitridae: Parabuteo unicinctus | Estimated | [12] |
Related animals
- Harris's hawk same vision type
- Black kite same vision type
- Egyptian vulture same vision type
- Griffon vulture same vision type
- Red-tailed hawk same vision type
- Turkey vulture same vision type
More birds: all birds with measured vision data.
Sources
- Lind O, Mitkus M, Olsson P, Kelber A. 2014. Ultraviolet vision in birds: the importance of transparent eye media. Proc R Soc B 281:20132209. Table 1. doi.org/10.1098/rspb.2013.2209
- 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, Brandley NC, Johnsen S (2018) Visual acuity and the evolution of signals. Trends Ecol Evol 33:358-372. Supplementary Tables S1-S3.. doi.org/10.1016/j.tree.2018.03.001
- 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
- Potier S, Mitkus M, Kelber A (2020) Visual adaptations of diurnal and nocturnal raptors. Semin Cell Dev Biol 106:156-164. Table 1.. doi.org/10.1016/j.semcdb.2020.05.004
- Portugal SJ, Ozturk R, Murn CP, Potier S, Martin GR. 2023. Current Biology 33:R1142-R1143. doi.org/10.1016/j.cub.2023.09.016
- Tyrrell LP, Moore BA, Loftis C, Fernandez-Juricic E 2017 (data 2017). The hawk-eyed songbird: retinal morphology, eye shape, and visual fields of an aerial insectivore. Am Nat 189(6). Dryad doi:10.5061/dryad.n7140.. doi.org/10.1086/691404
- Potier S, Mitkus M, Bonadonna F, Duriez O, Isard P-F, Dulaurent T, Mentek M, Kelber A 2017. Eye size, fovea, and foraging ecology in accipitriform raptors. Brain Behav Evol 90: 232-242. Supplementary material (Tables S1, S2).. doi.org/10.1159/000479783
- Light conditions and the evolution of the visual system in birds (figshare dataset, SupplementaryDataset1). doi.org/10.6084/m9.figshare.22116371.v3
- Wilman H, Belmaker J, Simpson J, de la Rosa C, Rivadeneira MM, Jetz W. 2014. EltonTraits 1.0: species-level foraging attributes of the world's birds and mammals. Ecology 95:2027. BirdFuncDat.txt. doi.org/10.6084/m9.figshare.3559887.v1
- 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
- Lafitte A, Sordello R, Legrand M, Nicolas V, Obein G, Reyjol Y. 2022. A flashing light may not be that flashy: A systematic review on critical fusion frequencies. PLoS ONE 17(12): e0279718. S10 File (CFF database). doi.org/10.1371/journal.pone.0279718
- 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
- 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
Every value cites its sources (all sources). Data: catalogue-v1, built 2026-09-29. Accuracy notes: how accurate is this?