carcinisation

Carcinisation (or carcinization) is a hypothesised process whereby a crustacean evolves into a crab-like form from a non-crab-like form. The term was introduced by L. A. Borradaile, who described it as "one of the many attempts of Nature to evolve a crab".

Carcinisation is believed to have occurred in at least five groups of decapod crustaceans, independently, most notably king crabs which most scientists believe evolved from hermit crab ancestors (there is still some debate over this point). The other examples are the family Porcellanidae, or porcelain crabs; these are closely related to squat lobsters, Lomis, Birgus latro, and the Brachyura itself (true crabs) [1].

The example of king crabs (family Lithodidae) evolving from hermit crabs has been particularly well studied and, although some doubt this theory, there is considerable evidence in its favour. For example: most hermit crabs are asymmetrical, so that they fit well into spiral snail shells; the abdomens of king crabs, even though they do not use snail shells for shelter, are also asymmetrical.

References

1. ^ Morrison, C L, A W Harvey, S Lavery, K Tieu, Y Huang & C W Cunningham (2001). Mitochondrial gene rearrangements confirm the parallel evolution of the crab-like form. Proc. Roy. Soc. Lond. B 269: 345–350. 
crustaceans (Crustacea) are a large group of arthropods, comprising approximately 52,000 described species [1], and are usually treated as a subphylum [2].
..... Click the link for more information.
Editing of this page by unregistered or newly registered users is currently disabled due to vandalism.
If you are prevented from editing this page, and you wish to make a change, please discuss changes on the talk page, request unprotection, log in, or .
..... Click the link for more information.
Brachyura
Latreille, 1802

Superfamilies
  • Section Dromiacea
  • Homolodromioidea
  • Dromioidea
  • Homoloidea

..... Click the link for more information.
Nature, in the broadest sense, is equivalent to the natural world, physical universe, material world or material universe. "Nature" refers to the phenomena of the physical world, and also to life in general.
..... Click the link for more information.
Decapoda
Latreille, 1802

Suborders

Dendrobranchiata
Pleocyemata
See text for superfamilies.

The decapods or Decapoda are an order of crustaceans within the class Malacostraca, including many familiar groups, such as crayfish,
..... Click the link for more information.
The term king crab is also sometimes used for the horseshoe crab Limulus.

King crabs

Paralithodes californiensis


Scientific classification

Kingdom: Animalia
..... Click the link for more information.

..... Click the link for more information.
Porcellanidae
Haworth, 1825

Genera
See text.

Porcelain crabs are decapod crustaceans in the family Porcellanidae, which superficially resemble true crabs.
..... Click the link for more information.
Galatheidae and Chirostylidae

Families and Genera
See text

Squat lobsters are decapod crustaceans of the families Galatheidae and Chirostylidae, including the common genera Galathea and Munida.
..... Click the link for more information.

..... Click the link for more information.
Birgus

Species: B. latro

Binomial name
Birgus latro
Linnaeus, 1767

Coconut crab distribution

..... Click the link for more information.
Brachyura
Latreille, 1802

Superfamilies
  • Section Dromiacea
  • Homolodromioidea
  • Dromioidea
  • Homoloidea

..... Click the link for more information.
Symmetry in common usage generally conveys two primary meanings. The first is an imprecise sense of harmonious or aesthetically-pleasing proportionality and balance; such that it reflects beauty or perfection.
..... Click the link for more information.
snail is loosely applied to almost all members of the molluscan class Gastropoda which have coiled shells in the adult stage.

The class Gastropoda is the second largest class of invertebrates, second only to the insects.
..... Click the link for more information.
shell is a hard, rigid outer layer, which has evolved in a very wide variety of different animals, including mollusks, sea urchins, crustaceans, turtles and tortoises, armadillos, etc.
..... Click the link for more information.
To comply with Wikipedia's this section of the article needs a complete rewrite.
Please discuss this issue on the talk page and read the layout guide to make sure the section will be inclusive of all essential details. This article has been tagged since September 2007.
..... Click the link for more information.


This article is copied from an article on Wikipedia.org - the free encyclopedia created and edited by online user community. The text was not checked or edited by anyone on our staff. Although the vast majority of the wikipedia encyclopedia articles provide accurate and timely information please do not assume the accuracy of any particular article. This article is distributed under the terms of GNU Free Documentation License.