Body plan
A body plan, Bauplan (pl. German: Baupläne), or ground plan is a set of morphological features common to many members of a phylum of animals.[1] The vertebrates share one body plan, while invertebrates have many.
This term, usually applied to animals, envisages a "blueprint" encompassing aspects such as
Body plans have historically been considered to have evolved in a flash in the
History
Among the pioneering
Linnaeus, 1735
In his 1735 book
Cuvier, 1817
In his 1817 work, Le Règne Animal, French zoologist
Grouping animals with these body plans resulted in four branches:
Haeckel, 1866
Gould, 1979
Origin
20 out of the 36 body plans originated in the
The current range of body plans is far from exhaustive of the possible patterns for life: the
Genetic basis
Genes, embryos and development together determine the form of an adult organism's body, through the complex switching processes involved in morphogenesis.
Developmental biologists seek to understand how genes control the development of structural features through a cascade of processes in which key genes produce morphogens, chemicals that diffuse through the body to produce a gradient that acts as a position indicator for cells, turning on other genes, some of which in turn produce other morphogens. A key discovery was the existence of groups of homeobox genes, which function as switches responsible for laying down the basic body plan in animals. The homeobox genes are remarkably conserved between species as diverse as the fruit fly and humans, the basic segmented pattern of the worm or fruit fly being the origin of the segmented spine in humans. The field of animal evolutionary developmental biology ('Evo Devo'), which studies the genetics of morphology in detail, is rapidly expanding[11] with many of the developmental genetic cascades, particularly in the fruit fly Drosophila, catalogued in considerable detail.[12]
See also
- Anatomical terms of location – Standard terms for unambiguous description of relative placement of body parts
- Arthropod head problem – Dispute concerning the evolution of arthropods
- Deep homology – Control of growth and differentiation by deeply conserved genetic mechanisms
- Evolutionary developmental biology – Comparison of organism developmental processes
- Definition of Phylum based on body plan – High level taxonomic rank for organisms sharing a similar body plan
- Ediacaran biota – All organisms of the Ediacaran Period (c. 635–538.8 million years ago)
- Macroevolution – Evolution on a scale at or above the level of species
- Precambrian body plans – Structure and development of early multicellular organisms
- Sean B. Carroll – American evolutionary developmental biologist
- Segmentation (biology) – Division of some animal and plant body plans into a series of segments
- Supernumerary body part – Growth of an additional part of the body and a deviation from the body plan
- Symmetry in biology – Geometric symmetry in living beings
References
- ^ ISBN 978-0226845487.
- ^ Linnaeus, Carolus (1735). Systema naturae, sive regna tria naturae systematice proposita per classes, ordines, genera, & species. Leiden: Haak. pp. 1–12.
- ISBN 978-0-520-94440-4.
- ^ ISBN 2-88074-264-1
- ^ Haeckel, Ernst. Generelle Morphologie der Organismen : allgemeine Grundzüge der organischen Formen-Wissenschaft, mechanisch begründet durch die von Charles Darwin reformirte Descendenz-Theorie. (1866) Berlin
- ^ Bowler, Peter J. (2009). Evolution: the History of an Idea. California, p. 364.
- ^ a b Erwin, Douglas; Valentine, James; Jablonski, David (1997). "The origin of animal body plans". American Scientist (March–April).
- .
- S2CID 39772232.
- S2CID 130602154.
- . Retrieved 13 September 2014.
- ISBN 0-521-77928-6.
External links
- Videos