Number and distribution of neurons in the retinal ganglion cell layer in relation to foraging behaviors of tyrant flycatchers.

The tyrant flycatchers represent a monophyletic radiation of predominantly insectivorous passerine birds that exhibit a plethora of stereotyped prey capture techniques. However, little is known about their retinal organization. Using retinal wholemounts, we estimated the total number and topography of neurons in the ganglion cell layer in the generalist yellow-bellied elaenia (Elaenia flavogaster) and the up-hover-gleaner mouse-colored tyrannulet (Phaeomyias murina) with the optical fractionator method.

The retina of tyrant flycatchers: topographic organization of neuronal density and size in the ganglion cell layer of the great kiskadee Pitangus sulphuratus and the rusty margined flycatcher Myiozetetes cayanensis (Aves: Tyrannidae).

Tyrant flycatchers comprise the largest group of passerine birds of the Neotropical region but their retinal organization is unknown. The great kiskadee, Pitangus sulphuratus, is categorized as a supreme generalist and utilizes a variety of foraging strategies. The rusty margined flycatcher, Myiozetetes cayanensis, is partially frugivorous and captures insects in the air.