Suma Harikumar R

Abstract Naturally occurring fluorescence has been observed in multiple species ranging from bacteria to birds. In macroscopic animals such as birds, fluorescence provides a visual communication signal. However, the functional significance of this phenomenon is unknown in most cases. Though photoprotection is attributed to fluorescence under ultraviolet (UV) light in some organisms, it lacks direct experimental evidence.

1. Background Tardigrades are microscopic (0.5 to 1 mm in length) animals with four pairs of legs. About 1300 species have been reported worldwide from various habitats [1–4]. The phylum Tardigrada is included in the superphylum Ecdysozoa along with its sister phyla: Arthropoda, Onychophora and Cycloneuralia [5].