|Three-spined stickleback, Gasterosteus aculeatus|
The Gasterosteidae are a family of fish including the sticklebacks. FishBase currently recognises sixteen species in the family, grouped in five genera. However several of the species have a number of recognised subspecies, and the taxonomy of the family is thought to be in need of revision. Although some authorities give the common name of the family as "sticklebacks and tube-snouts", the tube-snouts are currently classified in the related family Aulorhynchidae.
Stickleback are most commonly found in the ocean, but can be found in some freshwater lakes. The freshwater species were trapped in freshwater lakes in Europe, Asia and North America after the ice age, and have evolved different features from the ocean variety. They feed on small crustaceans and fish larvae.
Sticklebacks are distinguished by the presence of strong and clearly isolated spines in the dorsal fin. Their maximum length is about 4 inches, but few of them are more than 3 inches long. They mature sexually at a length of about 2 inches. All species show a similar mating behaviour, which is also unusual among fish. The males construct a nest from vegetation held together by secretions from their kidneys. The males then attract females to the nest. The female will lay their eggs inside the nest where the male can fertilise them. The male then guards the eggs until they hatch.
Three-spined stickleback 
The family includes the three-spined stickleback Gasterosteus aculeatus, common in northern temperate climates around the world including Europe, most of northern North America and Japan and colloquially known in the United Kingdom as the "tiddler", or "sprick". In the Republic of Ireland they are commonly known as "pinkeens" due to the reddish colour of the male three spined stickleback's throat during breeding season. Niko Tinbergen's studies of the behaviour of this fish were important in the early development of ethology as an example of a fixed action pattern. More recently, the fish have become a favorite system for studying the molecular genetics of evolutionary change in wild populations and a powerful "supermodel" for combining evolutionary studies at molecular, developmental, population genetic, and ecological levels. The nearly complete genome sequence of a reference freshwater stickleback was described in 2012, along with set of genetic variants commonly found in 21 marine and freshwater populations around the world. Some variants, and several chromosome inversions, consistently distinguish marine and freshwater populations, helping identify a genome-wide set of changes contributing to repeated adaptation of sticklebacks to marine and freshwater environments. 
Stickleback trap 
||This section contains instructions, advice, or how-to content. (September 2012)|
The common freshwater three-spined stickleback of Europe, Asia and North America may easily be caught in a simple trap made from a two-litre PET plastic soda bottle (capped) and the tapered top part of a one-litre PET plastic soda bottle (uncapped), glued or taped together as shown, weighted with a small piece of metal (a few inches of rebar is ideal) and left on the bottom of a pond or stream, or suspended horizontally in mid-water by two pieces of string, for an hour or two—the sticklebacks enter through the wide (but narrowing) entrance and cannot find their way back out. Bait is not necessary.
- The Repeater - NYTimes.com
- Orr, James W. & Pietsch, T.W. (1998). Paxton, J.R. & Eschmeyer, W.N., ed. Encyclopedia of Fishes. San Diego: Academic Press. pp. 171–172. ISBN 0-12-547665-5.
- "Three-spined stickleback". Gma.org. Retrieved 2012-08-31.
- "Irish poetry Ulster Scots". Webcitation.org. Retrieved 2012-08-31.
- Kingsley, D.M. and Peichel, C.L. (2007) The molecular genetics of evolutionary change in sticklebacks. in Biology of the three-spinestickleback. Ostlund-Nillson, S., Mayer, I. and Huntingford, F.A.(eds). CRC Press. pp. 41-81
- "The synthesis and evolution of a supermodel". Sciencemag.org. 2005-03-25. Retrieved 2012-08-31.
- "The genomic basis of adaptive evolution in threespine sticklebacks.". Nature.com. 2012-04-04.
- Froese, Rainer, and Daniel Pauly, eds. (2012). "Gasterosteidae" in FishBase. October 2012 version.
- Widespread Parallel Evolution in Sticklebacks by Repeated Fixation of Ectodysplasin Alleles by sciencemag.org
|Wikimedia Commons has media related to: Gasterosteidae|
- Chisholm, Hugh, ed. (1911). "stickleback". Encyclopædia Britannica (11th ed.). Cambridge University Press.
- 1930 Newsreel of Stickleback Building Nest by British Pathé