Beavertail cactus at the Mars Desert Research Station (MDRS) (image) Pensoft Publishers Share Print E-Mail Caption Beavertail cactus Opuntia basilaris var. basiliaris at the Mars Desert Research Station (MDRS). Credit Paul C. Sokoloff Usage Restrictions CC-BY 4.0 Share Print E-Mail Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.