Two possible depths of foveal pit

Range shallow 80-120 or deep 190-240 µm
Organism Birds
Reference Bringmann A. Structure and function of the bird fovea. Anat Histol Embryol. 2019 May48(3):177-200. doi: 10.1111/ahe.12432 abstract & p.189 left columnPubMed ID30734347
Method Abstract: "This review gives an overview of the cellular composition of the bird fovea, with special regard to Müller glial cells that provide the mechanical stability of the foveal tissue. A survey of previous data shows that the visual acuity of different bird groups (with the exception of owls) depends on the eye size, while the shape of the foveal pit does not correlate with the visual acuity."
Comments Abstract: "Among various bird groups, the foveal pit may have two depths, shallow (80-120 µm) or deep (190-240 µm)." P.189 left column: "Among different bird groups, there are two ranges of foveal depths: the central foveas of accipitriform, falconiform, coraciiform and passeriform birds have mean depths between 190 and 240 µm (in the mean, 218.6 ± 52.0 µm: n = 50), whereas the central foveas of psittaciform birds and domestic pigeons, as well as the temporal foveas of accipitriform, falconiform, coraciiform and strigiform birds, have mean depths between 80 and 120 µm (92.2 ± 51.0 µm: n = 36: p < 0.001: Figure 5b,c). The data suggest that the depth of the foveal pit does not explain the differences between the visual acuities of different bird groups."
Entered by Uri M
ID 117189