Premium
A PERSISTENT DIURNAL RHYTHM IN CHAOBORUS LARVAE. II. ECOLOGICAL SIGNIFICANCE 1
Author(s) -
LaRow Edward J.
Publication year - 1969
Publication title -
limnology and oceanography
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.7
H-Index - 197
eISSN - 1939-5590
pISSN - 0024-3590
DOI - 10.4319/lo.1969.14.2.0213
Subject(s) - sunset , larva , light intensity , rhythm , intensity (physics) , plankton , stratum , sediment , biology , ecology , environmental science , atmospheric sciences , geology , physics , paleontology , optics , acoustics
When Chaoborus larvae (Diptera:Culicidae) were kept under constant light conditions within sediment cores their distribution exhibited a 24‐hr periodicity. There was a gradual upward movement of larvae in the sediments; the greatest percentage ( x̄ = 90%) was consistently found in the 0–1‐cm stratum at solar sunset. The data indicate the larvae “test” the light conditions at the mud‐water interface at solar sunset. When the light intensity was below some critical threshold value, the larvae emerged and became planktonic. When the light intensity was above this value, the larvae reentered the sediments. The depth to which they burrowed was a function of the light intensity to which they were exposed. A method of resetting the endogenous rhythm in nature is proposed.