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orthogenesis

orthogenesis

1 9.9
A theory that animals and plants change in a fixed direction, not by natural selection
  • noun
  • /ˌɔrθəˈdʒɛnɪsɪs/
  • Archaic
: ortogenia
  • The concept of orthogenesis suggests that evolutionary changes follow a fixed direction.

Examples

  • The theory of orthogenesis is fascinating.

  • Many early biologists supported orthogenesis before the modern understanding of evolution emerged.

  • Most scientists today reject orthogenesis in favor of natural selection as the main driver of evolution.

  • Could orthogenesis explain the rapid development of certain species?

  • The concept of orthogenesis suggests that certain species evolve in a specific direction over time, rather than through random changes.

  • Many scientists studied orthogenesis in hopes of finding evidence for a predetermined path in the evolution of mammals.

  • Historically, orthogenesis was believed to explain the linear progression of traits in some species, but it is now largely discredited.

Antonyms

natural selection
  • Specialized
44 3.9

A process in which plants and animals better suited to their home survive and have more young

Surface Forms

orthogenesis singular
orthogeneses plural

Morphology

orthogenesis = genesis (semi-transparent) = ortho + genesis

The components 'ortho-' (straight/correct) and 'genesis' (origin) yield a literal sense of 'straight/oriented origin', but 'ortho-' is a technical combining form unfamiliar to many learners.

Etymology

Orthogenesis comes from Greek parts orthos 'straight' and genesis 'origin' or 'beginning', so you can picture evolution moving in a 'straight' line. That's why orthogenesis names the idea that evolution follows a set, directed path rather than changing only by natural selection.