Circadian advantage
A circadian advantage is an advantage gained when an organism's biological cycles are in tune with its surroundings. It is not a well studied phenomenon, but it is known to occur in certain types of cyanobacteria, whose endogenous cycles, or circadian rhythm, "resonates" or aligns with their environment. It is known to occur in plants also, suggesting that any organism which is able to attune its natural growth cycles with its environment will have a competitive advantage over those that do not. Circadian advantage may also refer to sporting teams gaining an advantage by acclimatizing to the time zone where a match is played.
In organisms
In the context of
Competition studies in plants provide another example of circadian advantage. These studies have shown that an endogenous clock that resonates with environmental cycles leads to a competitive advantage in Arabidopsis thaliana. [2] Experiments with wild type, short circadian period mutants, and long circadian period mutants demonstrated that plants with a circadian period that is optimally synchronized to the environment grew fastest. The same study also showed that photosynthetic carbon fixation was directly correlated to “circadian resonance”. A different study discovered that genes involved in photosynthetic reactions of A. thaliana are under clock control. mRNAs that encode chlorophyll binding proteins and the enzyme protoporphyrin IX magnesium chelatase involved in chlorophyll synthesis were cycling.[3] The “circadian resonance” increase in productivity may arise from appropriate anticipation of sunrise and sunset, allowing for timely synthesis of light-harvesting complex proteins and chlorophyll. Therefore, the competitive advantage in A. thaliana further supports the idea that anticipation of environmental changes leads to enhanced fitness.
Rhodopseudomonas palustris is another example of the advantage in having a biological timing system that interacts with the environmental cycles. While the only prokaryotic group with a well-known circadian timekeeping mechanism is the cyanobacteria, recent discoveries involving R. palustris have suggested alternative timekeeping mechanisms among the prokaryotes.[4] R. palustris is a purple non-sulfur bacterium that has KaiB and KaiC genes and exhibit adaptive kaiC-dependent growth in 24h cyclic environments. However, R. palustris was reported to show a poorly self-sustained intrinsic rhythm, and kaiC-dependent growth enhancement was not present under constant conditions. The R. palustris system was proposed as a “proto” circadian timekeeper that exhibit some parts of circadian systems (kaiB and kaiC homologs), but not all.
Likewise, research on the endogenous circadian timekeeping mechanisms in mice further supports that “circadian resonance” is evolutionarily adaptive. One study in particular compared the fitness of wild-type mice with mutant mice which had a short free-running circadian cycle.[5] These mice had a mutation in the casein kinase 1Ɛ gene, which encodes an enzyme that is integral in controlling circadian cycle length. A mixed group of wild-type and mutant mice were then released in an outdoor experimental enclosure and, following a fourteen month timespan, the mice were monitored. The wild-type mice both survived longer and reproduced at a greater rate than the mutant mice. In fact, the mutant genotype was strongly selected against, thereby suggesting natural selection towards those genotypes that are resonant with the natural LD cycle.
It is possible that circadian clocks play a role in the gut microbiota behavior.[6] These microorganisms experience daily changes correlated with daily light/dark and temperature cycles. This occurs through behaviors such as eating rhythms on a daily routine (consumption in the day for diurnal animals and in the night for nocturnal animals). The presence of a daily timekeeper might give those bacteria a competitive advantage over others. By allowing the bacteria to sense resources coming from the host in order to prepare and metabolize them faster. There are bacteria that have daily timekeepers, and it may be possible that the microbiota have endogenous clocks which communicate with biological clocks of the host.[6] For instance, if there are some time-keeping qualities of the microorganisms within the intestines, it might be possible that they can affect the circadian system of the host. An endogenous clock may be present in some microbial species, and the presence of such an intrinsic timekeeper could be beneficial both in the gut (which experiences daily changes in nutrient availability) and the environment outside of the host (which experiences daily cycles of light and temperature).[6]
In sport
In
Using the convention that for every time zone crossed, synchronization to that time zone requires one day, teams can be analyzed during a season to see where they are in terms of being acclimated to their time zone of play. For example, consider the Washington Nationals. If they have been competing at home for the last 3 days or more, they would be completely acclimated to Eastern Standard Time (EST). If they were to travel to Los Angeles, upon arrival they would be 3 hours off, because they traveled 3 time zones west. Every 24 hours spent on the west coast, would bring them 1 hour closer to acclimation.[11] So after 24 hours in Los Angeles, they would be 2 hours off. After 48 hours, they would be 1 hour off, and after 72 hours, they would be acclimated to west coast time and would stay that way until they left their time zone.
Unlike
Circadian advantage is most significant when a team holds a 3-hour advantage (or more) over another. This matchup is only encountered after very long flights where the traveling team plays soon after arrival, most commonly coast-to-coast flights in major North American and Australian leagues. As the magnitude of time zone differences between two teams becomes smaller, so too does circadian advantage.
In 2018, pilot data collected by Walter Reed Army Institute of Research, was presented at the American Academy of Sleep Medicine's annual SLEEP meeting suggested National Football League teams perform better at night versus the day as a result of circadian advantage. It also indicated that teams had fewer turnovers at night.[12]
References
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- ^ Winter WC, Hammond WR, Vaughn BV (2005). "Tracking 'Circadian Time' as a Statistic During the 2004 Major League Baseball Season: A Pilot Study". Sleep. 28: 64–5.
- PMID 19953826.
- ^ Arendt J, Stone B, Skene D (2000). "Jet Lag and Sleep Disruption.". In Kryger MH, Roth T, Dement WC (eds.). Principles And Practice of Sleep Medicine (3rd ed.). W.B. Saunders. p. 591.
- .
Further reading
- Nikhil Swaminathan (2008-06-10). "Out of the Zone: Jet-Lagged Baseball Teams Suffer Disadvantage". Scientific American. Retrieved 2008-06-17.
- "The Circadian Advantage". Science Friday. National Public Radio. 2008-06-13. Archived from the original on 2008-09-08. Retrieved 2008-06-17.
- Randy Dotinga (2008-06-11). "Baseball Teams Strike Out When Jet-Lagged". ABC News (also seen on Forbes.com and WashingtonPost.com). Retrieved 2008-06-17.
- Shari Roan (2008-06-10). "Can A Good Night's Sleep Save The Lakers?". LA Times. Retrieved 2008-06-17.
- Nicholas Bakalar (2008-06-29). "Traveling Through Time Zones Can Take Toll on Teams". The New York Times. Retrieved 2008-06-28.
- Lloyd, Robert (2008-06-17). "Study explains Cubs' fall in '84". The Chicago Tribune. Retrieved 2008-08-27.
- Austin Kelley (2009-07-17). "Baseball Veers Into Left Field". The Wall Street Journal. Retrieved 2009-07-17.
- Tina Hesman Saey (2008-06-10). "Time On Their Side". Science News. Retrieved 2008-06-17.
- Jennifer Cutraro (2008-06-20). "For Kids: Hey Batter, Wake Up!". Science News. Retrieved 2008-06-20.
- Michael Smith (2008-06-10). "APSS: Time Zones Can Offer a Major League Edge (w/video interview)". MedPage Today. Retrieved 2008-06-17.
- "Major League Baseball Teams With Greater Circadian Advantage Are More Likely To Succeed". Science Daily. 2008-06-10. Retrieved 2008-06-17.
- Scott Soshnick (2008-07-02). "Sport Business Battle is Being Won By Business". Bloomberg News. Retrieved 2008-07-02.
- Matt Ford (2008-06-13). "The importance of sleep in sports and school". ars technica. Retrieved 2008-06-17.
- Jennifer Black (2008-06-30). "Major League Baseball Funds Local Doctor's Study". CBS 19 Charlottesville. Archived from the original on 2013-04-19. Retrieved 2008-06-30.
- "NFL teams play better during night games thanks to circadian advantages". American Academy of Sleep Medicine. 2018-06-04. Retrieved 2018-06-04.