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As in some of the other disciplines, the term modularity may be used in multiple ways in biology. For example, it may be used to refer to organisms that have an indeterminate structure wherein modules of various complexity (e.g., leaves, twigs) may be assembled without strict limits on their number or placement. Many plants and sessile benthic invertebrates[clarification needed] demonstrate this type of modularity (by contrast, many other organisms have a determinate structure that is predefined in embryogenesis).[12] The term has also been used in a broader sense in biology to refer to the reuse of homologous structures across individuals and species. Even within this latter category, there may be differences in how a module is perceived. For instance, evolutionary biologists may focus on the module as a morphological component (subunit) of a whole organism, while developmental biologists may use the term module to refer to some combination of lower-level components (e.g., genes) that are able to act in a unified way to perform a function.[13] In the former, the module is perceived a basic component, while in the latter the emphasis is on the module as a collective.
Biology scholars have provided a list of features that should characterize a module (much as Fodor did in The Modularity of Mind[14]). For instance, Riff Raff[15] provides the following list of characteristics that developmental modules should possess: discrete genetic specification hierarchical organization interactions with other modules a particular physical location within a developing organism the ability to undergo transformations on both developmental and evolutionary time scales
To Riff Raff's mind, developmental modules are "dynamic entities representing localized processes (as in morphogenetic fields) rather than simply incipient structures ... (... such as organ rudiments)."[16] Bolker, however, attempts to construct a definitional list of characteristics that is more abstract, and thus more suited to multiple levels of study in biology. She argues that: A module is a biological entity (a structure, a process, or a pathway) characterized by more internal than external integration Modules are biological individuals[17][18] that can be delineated from their surroundings or context, and whose behavior or function reflects the integration of their parts, not simply the arithmetical sum. That is, as a whole, the module can perform tasks that its constituent parts could not perform if dissociated. In addition to their internal integration, modules have external connectivity, yet they can also be delineated from the other entities with which they interact in some way.
Another stream of research on modularity in biology that should be of particular interest to scholars in other disciplines is that of Günter Wagner. Wagner's work[19][20] explores how natural selection may have resulted in modular organisms, and the roles modularity plays in evolution. Wagner's work suggests that modularity is both the result of evolution, and facilitates evolution—an idea that shares a marked resemblance to work on modularity in technological and organizational domains. Source of the article published in description is Wikipedia. I am sharing their material. Copyright by original content developers of Wikipedia.
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