Definition: Living in the fluid medium (water or air) but unable to maintain their position or distribution independently of the movement of the water/air mass (adapted from Lincoln et al., 1998).
Definition: an animal that excavates holes or tunnels into soil or benthic sediment to create a space suitable for habitation, temporary refuge, or as a byproduct of locomotion. Inhabited burrows function as a refuge, protecting the inhabitants from predation and environmental extremes. They provide physical support for the digging and feeding activities of the burrow inhabitants. The harsh chemical environment deep in aquatic burrows must be counteracted by active or passive irrigation of burrow water.
Definition: an animal that excavates holes or tunnels into soil or benthic sediment to create a space suitable for habitation, temporary refuge, or as a byproduct of locomotion. Inhabited burrows function as a refuge, protecting the inhabitants from predation and environmental extremes. They provide physical support for the digging and feeding activities of the burrow inhabitants. The harsh chemical environment deep in aquatic burrows must be counteracted by active or passive irrigation of burrow water.
Definition: The marine benthic biome (benthic meaning 'bottom') encompasses the seafloor and includes such areas as shores, littoral or intertidal areas, marine coral reefs, and the deep seabed.
Definition: Eye-spots which may be set into a pit to reduce the angles of light that enters, to allow the organism to deduce the angle of incoming light. Lens-like structures may be present, but stemmata, unlike lens eyes, cannot form an image, either for lack of refractive power or retinal resolution.
