Water Bears Don’t Care –The Effects of Elevation on Tardigrade Class Distribution

Abstract

Previous studies aimed at elucidating the correlation between elevation and limno-terrestrial tardigrade distribution have been contradictory with positive, negative and no relationships being concluded. In particular, differences in the abundance of the two classes of tardigrades – Eutardigrada and Heterotardigrada – across various elevations has been observed but not studied. If elevation does affect tardigrade class distribution, one class of tardigrades should dominate over the other at different elevations. To better understand and clarify the relationship between tardigrade distribution and elevation, a minimum of three replicate samples of moss at three different elevations between 0m and 1010m were collected in Greater Vancouver for a total of 45 tardigrades identified by class. Data was analyzed by Two-way ANOVA to reveal no correlation between elevation and tardigrade class distribution with eutardigrades being dominant at every tested elevation. These results lend support to the idea that elevation may not be the key factor in determining the distribution of limno-terrestrial tardigrades.