orthogenesis

[ awr-thuh-jen-uh-sis ]

noun

1. Biology.
   1. Also called orthoselection. evolution of a species proceeding by continuous structural changes in a single lineage without presenting a branching pattern of descent.
   2. a theory that the evolution of a species in a continuous, nonbranching manner is due to a predetermined series of alterations intrinsic to the species and not subject to natural selection.
2. Sociology. a hypothetical parallelism between the stages through which every culture necessarily passes, in spite of secondary conditioning factors.

orthogenesis

/ ˌɔːθəʊˈdʒɛnɪsɪs; ˌɔːθəʊdʒɪˈnɛtɪk /

noun

1. biology
   1. evolution of a group of organisms predetermined to occur in a particular direction
   2. the theory that proposes such a development
2. the theory that there is a series of stages through which all cultures pass in the same order

Derived Forms

• orthogenetic, adjective
• ˌorthogeˈnetically, adverb

Word History and Origins

Origin of orthogenesis¹

From New Latin, dating back to 1890–95; ortho-, genesis

Example Sentences

The various models proposed for the mechanism of evolution, such as Lamarckian evolution, orthogenesis, and use-disuse, all implied some level of teleology, that there was a directionality inherent in the process.

From Scientific American

His goal was to study behavior, evolution, and genetics, and by working with such a wide variety of subjects he hoped to buttress his support of orthogenesis, a view that holds evolution to be “a directed and progressive process” determined by the characteristics of the species rather than the more random effects imposed by environment.

From Slate

On this basis Weismann attempts to reach explanations of the phenomena of variation, of many apparently Lamarckian phenomena, and of recognised cases of “orthogenesis,” and seeks to complete and deepen Roux's theory of the “struggle of parts,” which was just another attempt to carry Darwinism within the organism.

From Project Gutenberg

And thus we understand how it is that interpretations from the point of view of an inward law of development, of orthogenesis, or of teleology, notwithstanding their inherent validity, have à priori always had a relatively difficult position as compared with the Darwinian view.

From Project Gutenberg

They are usually associated with a denial of the theory of natural selection, and with theories of “Orthogenesis,” “Heterogenesis,” and “Epigenesis.”

From Project Gutenberg