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Scott Gilbert proposes that the morphogenetic field is a middle ground between genes and evolution.[3] That is, genes act upon fields, which then act upon the developing organism.[3] Jessica Bolker describes morphogenetic fields not merely as incipient structures or organs, but as dynamic entities with their own localized development processes, which are central to the emerging field of evolutionary development ("evo-devo").[8]
By the 1930s, however, the work of geneticists, especially ontogeny.[3] With the discovery and mapping of master control genes, such as the homeobox genes the pre-eminence of genes seemed assured. But in the late twentieth century the field concept was "rediscovered" as a useful part of developmental biology. It was found, for example, that different mutations could cause the same malformations, suggesting that the mutations were affecting a complex of structures as a unit, a unit that might correspond to the field of early 20th century embryology.
Harrison was able to identify "fields" of cells producing organs such as limbs, tail and gills and to show that these fields could be fragmented or have undifferentiated cells added and a complete normal final structure would still result. It was thus considered that it was the "field" of cells, rather than individual cells, that were patterned for subsequent development of particular organs. The field concept was developed further by Harrison's friend Hans Spemann, and then by Paul Weiss and others.[3]
The concept of the morphogenetic field, fundamental in the early twentieth century to the study of embryological development, was first introduced in 1910 by Alexander G. Gurwitsch.[6] Experimental support was provided by Ross Granville Harrison's experiments transplanting fragments of a newt embryo into different locations.[7]
[5] are examples of morphogenetic fields.larvae in insect Imaginal discs [4] Importantly, however, the specific cellular programming of individual cells in a field is flexible: an individual cell in a cardiac field can be redirected via cell-to-cell signaling to replace specific damaged or missing cells.[4] will become heart tissue.cardiac field will become a limb tissue, those in a limb field As a group, the cells within a given morphogenetic field are constrained — i.e. cells in a [3]
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