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                                       Details for article 1 of 12 found articles
 
 
  Analysis and comparison of circadian rhythms of subarctic and central European beetles of the Carabid species Pterostichus nigrita Paykull (Coleoptera, Carabidae)
 
 
Title: Analysis and comparison of circadian rhythms of subarctic and central European beetles of the Carabid species Pterostichus nigrita Paykull (Coleoptera, Carabidae)
Author: Leyk, Gisela
Appeared in: Biological rhythm research
Paging: Volume 12 (1981) nr. 2 pages 117-128
Year: 1981-05
Contents: The entrainment of the circadian locomotor activity of subarctic and Central European beetles of the Carabid species Pterostichus nigrita to different Zeitgeber conditions was studied. Various light-dark cycles such as artificial light, Central European natural light illumination in Cologne, and simulated subarctic light conditions during midsummer were used. A time series analysis of the data was performed with the computer program system “Timesdia”;. In various 24-h LD cycles with artificial light as well as under natural Central European light illumination the Central European beetles are generally stably entrained to the Zeitgeber with activity during the dark phase. In contrast to this behaviour subarctic beetles show: larger and more frequent changes of phase and amplitude, different phase relations and a higher amount of activity during the light phase. Under simulated subarctic midsummer light conditions the entrainment of the activity rhythms of the subarctic beetles is even less stable than in all other 24-h LD cycles. The Central European beetles show also more variations in phase and amplitude but most of the time one can still observe synchronization. Hence, one may conclude that in comparison with the “Central European”; Zeitgeber the “subarctic”; one is more weak. The less rhythmic behaviour and the higher amount of activity during the light phase as observed for the subarctic beetles in all experiments are regarded as adaptations to the subarctic photoperiodic conditions during midsummer with its continuous illumination. Zeitgeber conditions with other periods (12 h and 8 h) revealed definite differences between the populations as well. Whereas the typical behaviour of the Central European beetles was frequency-demultiplication (in LD 6:6) and relative coordination (in LD 4:4), the subarctic animals showed various reactions. Hence, one may conclude that there are definite differences between the populations and within the subarctic stock concerning the underlying control system.
Publisher: Taylor & Francis
Source file: Elektronische Wetenschappelijke Tijdschriften
 
 

                             Details for article 1 of 12 found articles
 
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