Sometimes called a “sand flea” or “beach hopper,” Parhyale hawaiensis (pronounced par-hi-alley) are tiny crustaceans that evolved 240 million years ago—about the same time as the dinosaurs. They live in tropical coastlines around the world and their populations can reach up to 7000 individuals per square meter. Parhyale are detritus feeders, meaning they feed on dead plant or animal matter, and are a vital part of many ecosystems.
Parhyale are considered the most genetically tractable research organism among crustaceans. The Parhyale genome was sequenced in 2016 and was found to be slightly larger than the human genome.
Parhyale are studied extensively by the Patel Lab at the MBL. These crustaceans have been used to explore the evolution of overall body patterning and led to a detailed understanding of how Parhyale are able to produce such a diversity of limb types along the length of their body. They have also been used to investigate the mechanisms of segmentation and an unusual phenomena of germline regeneration. Recent research by MBL scientists revealed that insect wings evolved from a lobe on the legs of their crustacean ancestors. In living crustaceans like Parhayle hawaiensis, these leg lobes form body wall armor, but as insects transitioned to land-dwelling about 300 million years ago, the leg lobe plates evolved into wings. The organisms are easy to rear and offer large broods of embryos amenable to injection, dissection, and live imaging. It is categorized as an emerging model organism as the main biological techniques necessary for the study of an organism have been established.