The Nikon MicroscopyU confocal microscopy image gallery was created with a PCM-2000 confocal scanning system interfaced to a Nikon Eclipse E600 upright microscope. Images were recorded in successive z-axis serial sections with C-Imaging Systems software with excitation illumination provided by an argon-ion and/or a helium-neon laser.

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Back to the first confocal sequence of lichen thallus.

Lichens are comprised of a species of fungus that forms an intimate survival arrangement with a species of algae. Fungus and algae will sometimes form beneficial relationships in order to endure environments where neither partner is likely to survive alone. Some lichens are thought to be among the oldest living organisms on earth and habitats range from the Arctic to Antarctic and include all regions in between. Various combinations may be found on bare rock, desert sand, dead wood, animal bones, rusty metal, and living bark. In the most barren parts of the world, lichens grow almost completely underground and obtain light and moisture through small cracks along the desert floor. Lichens are often the only plant to grow on bare rock where it collects moisture and very gradually breaks down stone to absorb tiny amounts of mineral matter. Over long periods of time (even centuries) the successful partnership gathers an extremely thin layer of soil which can eventually create a foundation in which other plants can take hold.

The shape and size of the lichen is primarily determined by the species of fungus and is manifested in as many different sizes, shapes, and colors. The organism grows in rosettes on trees, as crust atop rocks, in tangled threads from branches, and in tiny goblets on the ground. Lichens are a favorite food of reindeer and caribou, and during the winter months they sometimes dig craters in the snow to reach these morsels. More than fifty species of birds employ lichens as nest building materials. Vegetal dyes are often derived from lichens, the most scientifically renown being the dye referred to as litmus. Papers dyed with litmus change to red when exposed to acid and blue when exposed to alkali. A few varieties of lichen are poisonous.