"Tardigrada is an invertebrate phylum that comprises more than 959 species of micrometozoans, which size is up to 1.2 mm. Tardigrade are interesting by both, their capacity to survive under unfavourable conditions in a latency state called cryptobiosis, and their controversial phylogenetic position within Invertebrata. Tardigrade research has been restricted to the more basic topics (taxonomy and basic ecological patterns), being biased and incomplete. Remainder information continues to be neglected. As a result of this lack of information, the main objective of this proposal is to progress in knowledge on Tardigrada evolution, using all the information we will be able to generate. One of our main objectives will be to include more taxa (families Hypsibiidae, Calohypsibiidae and Macrobiotidae and, if possible, Microhypsibiidae, Necopinatidae, and Apodibius) and different genetic markers (5.8S rRNA, Histone H3, heavy chain of Myosin, elongation factors-1α and 2, RNA polymerase II, and EST sequences) in phylogenetic analyses. On the other hand, we would like to examine specimens from all genera from class Eutardigrada in Tardigrada collection from University of Copenhagen, to update morphological matrix from Guil´s Thesis with direct observations. Once we have a stable phylogeny, we will study the evolution of different characteristics in tardigrades (reproductive modes, their distribution through different habitats, claws and buccopharyngeal apparatus morphology, substances from cryptobiosis and cryptobiosis as a process itself), using the comparative method in phylogenetic analyses. An increase of knowledge within tardigrades will probably solve, or at least will help, to understand Ecdysozoan evolution, since this is, probably, a key taxa in evolutionary understanding. Furthermore, an innovative field such as biomedicine could use this information in its earliest steps, since they need basic evolutionary knowledge to progress."