Two Hypotheses about Hierarchies

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  • Date/Time:
    • Tuesday January 28, 2003 - Monday January 27, 2003
      12:00 pm - 11:00 pm
  • Location: MaRC auditorium
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Barbara Christopher
Industrial and Systems Engineering
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Summary Sentence: Two Hypotheses about Hierarchies

Full Summary: Two Hypotheses about Hierarchies

The aggregation of lower-level units into higher-level wholes seems to be correlated, in evolution, with two effects: 1) The loss of internal structure or complexity in the lower-level units; and 2) the emergence of complexity at an intermediate level. In effect, structural complexity is transferred from a lower level to a higher one. Thus, for example, cells in multicellular organisms seem to have fewer parts than free-living cells (protists), but multicellular organisms have intermediate-level parts, i.e., tissues and organs. At a higher level, the individuals in animal colonies seem to have fewer parts than their more solitary relatives, but individuals in colonies often collaborate to perform functions, again producing intermediate-level parts. These patterns have had little empirical support, so far, because operationalizing the key variable i.e., parts has been difficult. In this talk, I show how operationalization was achieved in a recent effort to document a part of the pattern, specifically the loss of parts in cell. Finally, this transfer of complexity across levels may be explained by a simple and fairly general logic, based on natural selection. If the explanation is right, the possibility arises that the pattern may be widespread, occurring in non-biological systems subject to similar constraints.

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H. Milton Stewart School of Industrial and Systems Engineering (ISYE)

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  • Created By: Barbara Christopher
  • Workflow Status: Published
  • Created On: Oct 8, 2010 - 7:42am
  • Last Updated: Oct 7, 2016 - 9:52pm