Rays
Rays are cartilaginous fish belonging to the superorder Batoidea, establishing them as close relatives of sharks and chimaeras. Like their shark counterparts, rays possess skeletons composed entirely of cartilage rather than bone. This shared anatomical trait reflects a common ancestry within the larger group of cartilaginous fishes, highlighting the evolutionary success of this body plan which has persisted for over 450 million years.
The group is distinguished by a flattened body shape and expansive, wing-like pectoral fins that are fused to the head. This dorsoventrally compressed morphology allows rays to glide efficiently through the water and bury themselves in sediment for camouflage or hunting. Their eyes and spiracles are typically located on the dorsal surface, while their gill slits and mouth are positioned ventrally, an adaptation suited for life near the sea floor.
During the Golden Age of Sharks, rays underwent significant diversification and adaptation. This period saw the emergence of various specialized forms, ranging from pelagic species to those adapted to benthic environments. Their evolutionary trajectory demonstrates a successful strategy for exploiting diverse ecological niches within marine ecosystems, complementing the broader narrative of cartilaginous fish evolution.
Source Notes
- 2026-04-07: How Sharks Lost Their Buzzsaws, Anvils, and Spikes
- 2026-04-08: The Golden Age of Shark Evolution and Bizarre Adaptations · ▶ source