Negative phototaxis in crustacean larvae: Possible functional significance

Published

Journal Article

Phototaxis of stage I larvae of the crab Rhithropanopeus harrisi (Gould) was quantitatively monitored by a microscope-television system. After dark-adaptation there is negative phototaxis only at the highest stimulus intensity, whereas the animals respond positively to intensities between 1.0 and 0.0006 W m-2. After light-adaptation there is positive phototaxis at intensities above 0.005 W m-2 while a negative response is observed to a lower range of intensities. Mean swimming speed during positive phototaxis does not vary with dark or light-adaptation or with stimulus intensity; however, during the negative response after light-adaptation speeds are intensity-dependent and are significantly faster at the highest response-initiating intensities than during a positive response. Arguments are presented to show that this negative response 1) may act as a shadow reflex, and 2) might be important in vertical movements. © 1974.

Full Text

Duke Authors

Cited Authors

  • Forward, RB

Published Date

  • January 1, 1974

Published In

Volume / Issue

  • 16 / 1

Start / End Page

  • 11 - 17

International Standard Serial Number (ISSN)

  • 0022-0981

Digital Object Identifier (DOI)

  • 10.1016/0022-0981(74)90069-0

Citation Source

  • Scopus