For 10 points, name this nematode.
One discovery in this organism was small, non-coding regions of RNA that bind to the 3-prime untranslated region of mRNA; that discovery was microRNA, examples of which include let-7 and lin-4. Mutant types of this organism include roller and dumpy. Application of a form of sequence-specific gene silencing, triggered by double-stranded RNA, to this organism won Craig Mello and Andrew Fire a Nobel. In response to harsh environmental conditions, it can undergo dauer arrest, which bypasses the L3 stage. That gene silencing technique is RNA interference. This pseudocoelomate can only be male or hermaphroditic, and Sydney Brenner's work popularized its use as a model organism. For 10 points, name this nematode.
One discovery in this organism was small, non-coding regions of RNA that bind to the 3-prime untranslated region of mRNA; that discovery was microRNA, examples of which include let-7 and lin-4.
Caenorhabditis elegans