Scientists surveying the deep seafloor of the Chilean Margin, in the southeastern Pacific, report observing tiny amphipod crustaceans clinging to giant sea spiders as the larger animals move along the ocean floor. The amphipods were seen on the spiders’ appendages at depths exceeding 3,000 meters.
The interaction is described as phoresis, where one organism uses another for transportation without being a parasite. Researchers say the arrangement allows weak-swimming amphipods to potentially travel farther than they could alone, which may help them encounter mates in a vast, sparsely populated deep-sea environment. The findings are presented as evidence of a previously underestimated behavior in deep-sea ecology, based on in situ observations collected during deep-water exploration.
Across the reports, the central point is consistent: amphipods are repeatedly found attached to the legs or other body parts of giant sea spiders in very deep waters, suggesting a deliberate ecological relationship. While one outlet emphasizes the transportation and mate-finding implications, both frame the observation as a form of hitchhiking rather than a direct feeding relationship.
