Quantification of ontogenetic discontinuities in three species of oegopsid squids using model II piecewise linear regression

  title={Quantification of ontogenetic discontinuities in three species of oegopsid squids using model II piecewise linear regression},
  author={Elizabeth K. Shea and Michael Vecchione},
  journal={Marine Biology},
Abstract. Growth trajectories of morphological characters may change during ontogeny, but this change is often overlooked or, at best, is estimated visually. An objective method was developed for determining discontinuities in morphological measurements of three species of oceanic squids: Chtenopteryxsicula (Vérany, 1851), Mastigoteuthismagna Joubin, 1913, and Brachioteuthis sp. 3. The specimens were collected on the Amsterdam Mid North Atlantic Plankton Expeditions (1980–1983) along a transect… 

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