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The stickleback family, Gasterosteidae, was first proposed as a family by the French zoologist Charles Lucien Bonaparte in 1831. [1] It was long thought that the sticklebacks and their relatives made up a suborder, the Gasterosteoidei, of the order Gasterostiformes with the sea horses and pipefishes making up the suborder Syngnathoidei.
The species occurs in freshwater systems draining into the Arctic Ocean and the Atlantic across Canada, Alaska, and south to New Jersey. It is present on the North American Pacific coast of Alaska and in the Great Lakes basin. It can also be found throughout most of Eurasia, including the United Kingdom, Greenland, Turkey and the Far East. [1]
Most species inhabit shallow, coastal waters, but a few are known from the open ocean, especially in association with sargassum mats. They are characterised by their elongated snouts, fused jaws, the absence of pelvic fins , and by thick plates of bony armour covering their bodies.
Under this classification system, Osteichthyes was considered paraphyletic with regard to land vertebrates, as the common ancestor of all osteichthyans includes tetrapods amongst its descendants. While the largest subclass, Actinopterygii (ray-finned fish), is monophyletic, with the inclusion of the smaller sub-class Sarcopterygii, Osteichthyes ...
Fishes are a paraphyletic group and for this reason, the class Pisces seen in older reference works is no longer used in formal taxonomy.Traditional classification divides fish into three extant classes (Agnatha, Chondrichthyes, and Osteichthyes), and with extinct forms sometimes classified within those groups, sometimes as their own classes: [1]
The three-spined stickleback appears to be a rather old species that has remained morphologically unchanged for more than 10 million years. The oldest record of the species is from the Alta Mira Shale of the Monterey Formation of California, which preserves an articulated skeleton that appears essentially identical to the modern G. aculeatus ...
Most species live on the sea floor, in a variety of geographical regions – mainly in coastal waters, although some live in deep waters to at least 3,000 metres (9,800 ft). Most batoids have a cosmopolitan distribution , preferring tropical and subtropical marine environments, although there are temperate and cold-water species.
This current formed 25–22 million years ago, and thermally isolated the Southern Ocean by separating it from the warm subtropical gyres to the north. During the mid-Tertiary period, a species crash in the Southern Ocean opened up wide range of empty niches to colonize. Despite the hemoglobin-less mutants being less fit, the lack of ...