In a great many of the contexts in which groups of cilia or flagella are found they exhibit synchronized behavior . This includes phase-locking , as seen in Chlamydomonas flagella {\it  , and metachronal wave formation in the ciliary arrays of Paramecium or in the respiratory cilia of URLanisms. Since the observations by Gray and Rothschild of phase synchrony of nearby swimming spermatozoa, it has been a working hypothesis that synchrony arises from hydrodynamic interactions between beating filaments. Recent work on the dynamics of physically separated pairs of flagella isolated from the multicellular alga Volvox {\it  has shown that hydrodynamic coupling alone is sufficient to produce synchrony. Moreover, when the flagellar power strokes are oriented in the same direction they synchronize in-phase, but when opposed they synchronize in antiphase. The situation is more complex when considering multiple flagellaon a single cell. Specifically, the unicellular biflagellate Chlamydomonasswims with opposing power strokes, yet synchronizes in phase in the familiar breaststroke. This indicates{\it   that a mechanism, internal to the cell, provides an additional flagellar coupling. Here we show that in comparison to the wildtype, markedly different synchronization states are found in Chlamydomonas mutants deficient in filamentary connections between basal bodies. Quantitative studies of complex flagellar coordination strategies found in quadri-, octo- and hexadecaflagellates reveal further evidence that intracellular couplings between flagellar basal bodies compete with hydrodynamic interactions to determine the precise form of flagellar synchronization in unicellular algae.
Cilia and flagella often exhibit synchronized behavior ; this includes phase locking , as seen in {\it Chlamydomonas , and metachronal wave formation in the respiratory cilia of URLanisms. Since the observations by Gray and Rothschild of phase synchrony of nearby swimming spermatozoa, it has been a working hypothesis that synchrony arises from hydrodynamic interactions between beating filaments. Recent work on the dynamics of physically separated pairs of flagella isolated from the multicellular alga {\it Volvox has shown that hydrodynamic coupling alone is sufficient to produce synchrony. However, the situation is more complex in URLanisms bearing few flagella. We show that flagella of{\it Chlamydomonas mutants deficient in filamentary connections between basal bodies display markedly different synchronization from the wild type. We perform micromanipulation on configurations of flagella and conclude that a mechanism, internal to the cell, must provide an additional flagellar coupling. In naturally occurring species with 4, 8, or even 16 flagella, we find diverse symmetries of basal body positioning and of the flagellar apparatus that are coincident with specific gaits of flagellar actuation, suggesting that it is a competition between intracellular coupling and hydrodynamic interactions that ultimately determines the precise form of flagellar coordination in unicellular algae.
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In a great many of the contexts in which groups of cilia or flagella are found they
Cilia and flagella often
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. This includes phase-locking
; this includes phase locking
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Chlamydomonas flagella
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Chlamydomonas
D
ciliary arrays of Paramecium or in the
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Volvox
A
Volvox
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Moreover, when the flagellar power strokes are oriented in the same direction they synchronize in-phase, but when opposed they synchronize in antiphase. The
However, the
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when considering multiple flagellaon a single cell. Specifically, the unicellular biflagellate Chlamydomonasswims with opposing power strokes, yet synchronizes in phase in the familiar breaststroke. This indicates
in URLanisms bearing few flagella. We show that flagella of
A
Chlamydomonas
A
mutants deficient in filamentary connections between basal bodies display markedly different synchronization from the wild type. We perform micromanipulation on configurations of flagella and conclude
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provides
must provide
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Here we show that in comparison to the wildtype, markedly different synchronization states are found in Chlamydomonas mutants deficient in filamentary connections between basal bodies. Quantitative studies of complex flagellar coordination strategies found in quadri-, octo- and hexadecaflagellates reveal further evidence that intracellular couplings between flagellar basal bodies compete with hydrodynamic interactions to determine
In naturally occurring species with 4, 8, or even 16 flagella, we find diverse symmetries of basal body positioning and of the flagellar apparatus that are coincident with specific gaits of flagellar actuation, suggesting that it is a competition between intracellular coupling and hydrodynamic interactions that ultimately determines
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synchronization
coordination