Marine vertebrates are vertebrates that live in marine environments. These are the. Fish mucus is supposed to reduce friction with the water during swimming. This assumption is based on the idea that mucus shows the 'Toms effect', which implies. They live near rivers, streams, ponds, small lakes, and marshes where they build their lodges of sticks and mud on islands, and banks (some beavers make. All animals that have a backbone are called vertebrates. They are generally the most familiar of animals, and include fish, amphibians, reptiles, mammals, and. Many vertebrates live in or near water, and most vertebrates can swim if necessary. Indeed, since fish are the most speciose ver-. Additionally, Laurin comments on the important role of paleontology in phylogenetic systematics as well as the nature of the fossil record and. The eggs of pelagic (open ocean) fishes usually remain suspended in the open water, while many shore and freshwater fishes lay eggs on the bottom or among. Vertebrate, any animal of the subphylum Vertebrata. Most species occur in near-shore waters, but some range widely throughout the oceans. The arteries in these birds run very close to veins so that they are warm enough to allow the bird to swim in very cold water. Many marine birds also have very. Around million years ago, late in what we call the Devonian era, the first fish began to crawl out of the primordial ooze and onto the.