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How do microvilli form the light-sensitive rhabdoms of many invertebrates?

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details of the mammalian eye — Photoreception The mammalian eye has a cornea and a lens and functions as a dioptric system, in which light rays are refracted to focus on the retina.

In many invertebrates, the light-sensitive rhabdom is formed by the interdigitation of fingerlike processes known as microvilli. These microvilli are contributed by a small number of photoreceptor cells, with eight being the typical number found in many insects.12

Structurally, these microvilli are microscopic, bristlelike protrusions supported by bundles of actin filaments, which help maintain their unique, highly curved form. Within the rhabdom, these microvilli are regularly arranged and serve as the site for photopigment molecules. Unlike the disks found in vertebrate photoreceptors, the photopigment molecules in invertebrate microvilli are often constrained to align with the axes of the microvilli. This specific organization allows many invertebrates, such as bees, to detect the plane of polarization of light, a capability that aids in navigation and environmental detection.231