Honey possum vision: the science and the numbers
Tarsipes rostratus · order Diprotodontia · Mammals: all the numbers
The honey possum has 3 colour receptor classes (363, 502 and 538 nm), one of them in the ultraviolet.[1][2][3] Its sharpest vision resolves 0.615 cycles per degree, against 63.75 for people in this dataset.[6][7]
- 3colour receptor classesMeasured
- 0.615cycles per degree (sharpness)Measured
The honey possum (Tarsipes rostratus) is a mammal in the order Diprotodontia. Its eyes belong to the vision type Small prey mammal (UV): two or three cone types, often including ultraviolet, low sharpness and a near-panoramic field. Measured in this species: colour, sharpness and night vision. Measured core: measured values on at least 3 of the 6 dials.
This is a simulation built from published eye measurements, not what the animal experiences.
What the honey possum sees: colour receptors
What stands out
- It has three colour receptor classes, like most people, but one of them sees ultraviolet.
- Its sharpest vision resolves 0.615 cycles per degree: the finest stripe pattern it can tell apart from grey.
- Activity pattern: nocturnal.
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. The last column gives the values for people from the same catalogue.
| Dial | Value | Evidence | Sources | People |
|---|---|---|---|---|
| Colour | Colour receptors 3 receptor classes: 363 nm (UVS), 502 nm (MWS (green)), 538 nm (MWS (green)) measured in this species | Measured | [1][2][3] | Colour receptors: 3 receptor classes: 421.5 nm (VS/SWS (violet)), 532 nm (MWS (green)), 558.4 nm (LWS (long)) Measured (not re-verified)[2][4][1][5] |
| Ultraviolet yes: at least one receptor peaks in the ultraviolet | Measured | |||
| Sharpness | Acuity 0.615 cycles per degree median of 2 behavioural rows (method priority rule) | Measured | [6][7] | Acuity: 63.75 cycles per degree Measured[7][8] |
| Field of view | Binocular overlap 92.5° median of 2 relatives in order Diprotodontia: Trichosurus vulpecula, Macropus eugenii | Group default | [9] | Binocular overlap: 122.5° Measured[9][10] Total field of view: 200° Measured (not re-verified)[11] Blind area behind the head: 160° Derived[11] Eye placement: frontal Derived[9][10] |
| Sharp zones (foveas) | Number of foveas 0 median of 80 relatives in class Mammalia: Canis lupus, Vulpes lagopus, Acinonyx jubatus, Felis catus, Crocuta crocuta, Enhydra lutris | Group default | [12] | Number of foveas: 1 Measured[12] Fovea type: fovea Measured[12] |
| Fovea type area centralis | Group default | [12] | ||
| Night vision | Activity pattern nocturnal mode of 8 rows (of 9 rows): cathemeral; crepuscular; mixed (nocturnal/crepuscular, cathemeral, crepuscular or diurnal/crepuscular); nocturnal | Measured (not re-verified) | [13][14][15][16][17][18][8] | Activity pattern: diurnal Measured (not re-verified)[13][14][15][2][16][17][19][18] Pupil shape: vertical Group default[20][21] Reflective layer (tapetum): no Measured[22] Rods vs cones: cone-dominated Derived[13][14][15][2][16][17][19][18] |
| Rods vs cones rod-dominated nocturnal -> rod-dominated; crepuscular / cathemeral / mixed -> mixed; diurnal -> cone-dominated | Derived | [13][14][15][16][17][18][8] | ||
| Motion (flicker fusion) | Flicker fusion frequency 22.4 Hz median of 1 relatives in order Diprotodontia: Trichosurus vulpecula | Group default | [23] | Flicker fusion frequency: 60 Hz Measured[24][25] |
All mammals side by side: Mammals: every measurement. Method: how we know what animals see.
Sources
- Müller et al. 2009
- Longcore 2023
- VPOD in-vivo (MSP / single-cell) lambda… 2025
- Kirwan
- Thermal Activation and Photoactivation of Visual… 2004
- Caves et al. 2024
- Kirk et al. 2004
- Veilleux et al. 2014
- Heesy 2004
- Heffner et al. 1992
- Campbell & Green 1965
- Kopania et al. 2025
- Anderson et al. 2017
- Borges et al. 2018
- Wilman et al. 2014
- Maor et al. 2017
- Jones et al. 2009
- Moura et al. 2024
- Schmitz et al. 2011
- Banks et al. 2015
- Cervino et al. 2021
- Guareschi et al. 2025
- Haarlem et al. 2026
- Healy et al. 2013
- Inger et al. 2014
Every value cites its sources (all sources). Values were extracted from these works and converted (units, medians, derived values); changes are ours, and the listed sources do not endorse this site. Data: catalogue-v1, built 2026-09-29. Accuracy notes: how accurate is this? Method: how we know.