Vertebrates: Fish
While, according to Stephen Jay Gould (1941–2002), there is “no such thing as a fish”, the term ‘fish’ can still be usefully and accurately applied when describing particular groups of aquatic animals. For example, cartilaginous fish (Chondrichthyes) include sharks, rays, sawsharks and chimaeras, which are animals that have inherited a skeleton constructed mostly of cartilage from the ancestor they shared most recently. Ray-finned fish (Actinopterygii) are aquatic animals with mineralised skeletons, with most species in the group having pectoral fins that fan open with the support of thin bones. There are far more species of ray-finned fish living today than there are of cartilaginous fish or any other major group of animals with vertebrae, and we are fortunate to have discovered spectacular examples of both Actinopterygii and Chondrichthyes fossils in Aotearoa New Zealand.
This section introduces some of the cartilaginous and ray-finned fish that are part of the Geology Museum collections. These specimens have been collected from both freshwater and marine depositional environments, and have been recognised from isolated teeth, earbones, or recovered as nearly complete skeletons. Fossil fish are a very important area of vertebrate paleontology which is still relatively understudied in New Zealand. Thus, there are many great opportunities for future researchers to contribute to the fossil record of New Zealand by studying something which famously doesn’t exist.
Gould, SJ. 1983. Hen's Teeth and Horse's Toes: Further Reflections in Natural History. New York: W.W. Norton & Company, Inc.
Page 363: "...Some of our most common and comforting groups no longer exist if classifications must be based on cladograms. With apologies to Mr. Walton and to so many coastal compatriots in New England, I regret to report that there is surely no such thing as a fish. About 20,000 species of vertebrates have scales and fins and live in water, but they do not form a coherent cladistic group. Some—the lungfishes and the coelacanth in particular—are genealogically close to the creatures that crawled out on land to become amphibians, reptiles, birds, and mammals..."
Firm, flexible connective tissue found. One of two major components in the skeleton of all vertebrates (with the other being a calcium phosphate mineral).
Connective tissues with a high proportion of accumulated minerals, generally a calcium phosphate mineral (bone) or a calcium carbonate mineral (shell). Mineralised tissues including bones and teeth are harder and more durable than cartilage-only skeletal tissues.
The pair of fins located on either side of the body near the gills.
The series of bones forming the flexible 'backbone' structure of the animals named for possessing these bones, the vertebrates.
Evidence of life from a past geological age. Remains like bones, shells or wood, or an impression like a footprint, or some other evidence of life, from something that was alive more than 11,700 years ago.
Sometimes called 'earbones', but more correctly termed 'ear stones', these are accumulations of calcium carbonate minerals in the base of the skull of many vertebrates that help to provide a sense of movement and maintain balance.
