Record Details
Field | Value |
---|---|
Title | Endogenous activity rhythms of the vertically migrating ocean shrimp |
Names |
Frey, John Richard
(creator) Pearcy, William G. (advisor) |
Date Issued | 1973-05-11 (iso8601) |
Note | Graduation date: 1974 |
Abstract | This study is an investigation of the endogenous, or internal, rhythms of activity in the ocean shrimp, Pandalus jordani, Groups of shrimp were kept in constant light and temperature conditions in the laboratory, and activity was monitored visually and with infrared photography. Other groups of animals were exposed to 24-hour light-. dark cycles of blue-green light; the activity of these animals was recorded with infrared photography after the light cycle was terminated. It was found that shrimp not exposed to a light-dark cycle did not display any rhythms of activity in constant conditions in the laboratory. After exposure to the light cycle, some shrimp swam significantly more during the 'night" hours in constant conditions. These shrimp 'entrained" to the light cycle; they synchronized their activity with the periodicity of the light cycle, and retained the periodicity in the absence of the rhythmical light cues. The relationship of these results to the nocturnal vertical migration of ocean shrimp in the field is discussed. It is suggested that shrimp possess a biological clock which synchronizes with rhythmical light cues and mediates vertical swimming, and that the rhythmicity of the vertical migration in the field is endogenous, with internal and external factors interracting with the internal rhythm. Conclusions are summarized and areas for further research are suggested. |
Genre | Thesis/Dissertation |
Topic | Shrimps |
Identifier | http://hdl.handle.net/1957/28425 |