Bony Fish
Evolved at ca. same time as sharks
Freshwater origin (unlike sharks)
Skeleton is ossified: evolutionary origin from shark that started covering the outer layer of cartilage skeleton with bone material
Exoskeleton: bony fish scales are also ossified; different types of fish scales
Evolutionary origin from spiny sharks,which had also bony plates in their skin
Ray-finned fish: internal skeleton of parallel bony rays that support and stiffen fins; no muscles in fins; some fins movable
Bony skeleton is heavier than cartilage skeleton; however, it provided more stability