Related Experiment Video
Updated: Jul 10, 2026
10:38
Monitoring Cell-autonomous Circadian Clock Rhythms of Gene Expression Using Luciferase Bioluminescence Reporters
Published on: September 27, 2012
Illuminating the circadian clock in monarch butterfly migration
Oren Froy1, Anthony L Gotter, Amy L Casselman
1Department of Neurobiology, University of Massachusetts Medical School, LRB-728, 364 Plantation Street, Worcester, MA 01605, USA.
Science (New York, N.Y.)
|May 24, 2003
Summary
Migratory monarch butterflies rely on a time-compensated Sun compass for navigation. Constant light disrupts this compass, impacting flight navigation, while ultraviolet light is crucial for navigation but not circadian rhythm entrainment.
Area of Science:
- Animal behavior
- Chronobiology
- Neuroethology
Background:
- Monarch butterflies navigate using a time-compensated Sun compass.
- Circadian clock function is essential for this navigation.
- Light cues play a critical role in both circadian rhythms and navigation.
Purpose of the Study:
- To investigate the effect of constant light on monarch butterfly navigation.
- To determine the role of ultraviolet light in monarch flight navigation and circadian entrainment.
- To elucidate the distinct light-input pathways for clock-compass mechanisms.
Main Methods:
- Constant light exposure experiments on monarch butterflies.
- Behavioral assays to assess flight navigation accuracy.
- Molecular analysis of circadian clock function.
- Photoperiod manipulation experiments focusing on ultraviolet light.
Main Results:
- Constant light disrupts the time-compensated Sun compass in monarchs.
- Disruption of circadian clock function by constant light impairs navigation.
- Ultraviolet light is essential for flight navigation.
- Ultraviolet light is not required for photic entrainment of circadian rhythms.
Conclusions:
- Disrupting circadian clock function with constant light impairs monarch butterfly navigation.
- Distinct neural pathways likely process light for circadian rhythms and Sun compass navigation.
- Understanding these pathways is key to deciphering monarch migration mechanisms.
Related Concept Videos
00:53Migration
Migration is long-range, seasonal movement from one region or habitat to another. This common strategy, carried out by many different organisms around the world, is an adaptive response that typically corresponds to changes in an organism’s environment, like resource availability or climate. Migrations can involve huge groups of thousands of animals as well as single individuals traveling alone and can range from thousands of kilometers to just a few hundred meters.
02:45Biological Clocks and Seasonal Responses
The circadian—or biological—clock is an intrinsic, timekeeping, molecular mechanism that allows plants to coordinate physiological activities over 24-hour cycles called circadian rhythms. Photoperiodism is a collective term for the biological responses of plants to variations in the relative lengths of dark and light periods. The period of light-exposure is called the photoperiod.
02:19Circadian Rhythms and Gene Regulation
The biological clock is involved in many aspects of regulating complex physiology in all animals. It was in 1935 when German zoologists, Hans Kalmus and Erwin Bünning, discovered the existence of circadian rhythm in Drosophila melanogaster. However, the internal molecular mechanisms behind the circadian clock remained a mystery until 1984, when Jeffrey C. Hall, Michael Rosbash, and Michael W. Young discovered the expression of the Per gene oscillating over a 24-hour cycle. In subsequent years,...
01:12Setting Time of Cement
The setting time of cement refers to the process of cement paste transitioning from a plastic state to a solid state. This process is crucial in construction as it dictates the timeframe for concrete placement, compaction, and finishing. The onset of this solidification is termed the initial set, indicating when the paste becomes unworkable. The final set is when the paste has solidified completely, and further handling or manipulation can no longer affect its shape. The cement strength is...
01:28Meridians
In surveying, meridians are vital reference lines to measure directions and establish accurate land orientations. Meridians run from the north to the south poles, providing a stable framework for angular measurements and mapping. Meridians are fundamental in survey design, with the primary types being astronomic, magnetic, and assumed meridians. Each type offers distinct benefits and limitations, selected based on the project's scale and precision needs.The astronomic meridian is aligned with...
01:19Magnetic Declination
Magnetic declination is the angle between true north, which aligns with the Earth's rotational axis, and magnetic north, which follows the direction of the Earth's magnetic field. This discrepancy exists because the magnetic poles do not coincide with the geographic poles. The value of magnetic declination depends on the observer's location on Earth and is subject to changes over time due to the dynamic nature of the Earth's magnetic field.The declination is called eastern when magnetic north...