"The entire issue of the November 29 Philosophical Transactions: Biological Sciences of the Royal Society of London is devoted to “Complex Clocks.”
Some statements from Fred Kippert’s introduction indicate that molecular biologists, “reductionist by vocation,” have their hands full trying to understand the multiple interacting systems that resist simplistic models.
The central theme of both special issues is ‘complexity’ – apparently nothing new for biological systems.
-We can now emphasize the complexity of circadian systems as we have recently gained enough knowledge to free ourselves from the inheritance of a past of looking for simple loops and cycles.
-As with any other sensory function, circadian systems need to discriminate between signal and noise. One way of doing so is to ‘probe’ actively for signals, modulating the strength of a given physical or chemical stimulus according to circadian time rather than passively responding to them. This creates ‘zeitnehmer’ (time taker) loops that are both input and output of the clock (an unimaginable complexity for the simple sequential model) which have the
interesting consequence of increasing the robustness of the system.
-Another aspect of complexity is the presence of several oscillators in the same organism. Circadian clocks are not confined to the central nervous system but are also present in peripheral organs: examples have been found in invertebrates, like fruit flies and moths, and in vertebrates, like zebra fish and mouse.
-We can now emphasize the complexity of circadian systems as we have recently gained enough knowledge to free ourselves from the inheritance of a past of looking for simple loops and cycles.
-As with any other sensory function, circadian systems need to discriminate between signal and noise. One way of doing so is to ‘probe’ actively for signals, modulating the strength of a given physical or chemical stimulus according to circadian time rather than passively responding to them. This creates ‘zeitnehmer’ (time taker) loops that are both input and output of the clock (an unimaginable complexity for the simple sequential model) which have the
-Another aspect of complexity is the presence of several oscillators in the same organism. Circadian clocks are not confined to the central nervous system but are also present in peripheral organs: examples have been found in invertebrates, like fruit flies and moths, and in vertebrates, like zebra fish and mouse.
Peripheral oscillators are self-sustained, as evinced by in vitro studies, but show a great deal of variation in their robustness and responsiveness to external (i.e. light) and/or internal (i.e. hormonal and neuronal) stimuli.
The physiological implications of relying upon a multi-oscillator system are particularly evident in birds. The avian time-keeping system is the product of the dynamic interplay between anatomically distinct pace-maker components. The flexibility in the interaction is particularly important in helping the circadian system cope with extreme environmental conditions such as those experienced by high-Arctic (low-amplitude light variations in midsummer) or migratory (travel between time zones) birds.
----the conferees were not “surprised to also find complexity in biological timing mechanisms, considering that they have evolved in response to a complex environment (which we fail to reproduce in our simple artificial laboratory conditions) …. Their contribution brings into focus once again the notion, held all along by the honouree of the conference, that complex environments will necessarily breed complex timing mechanisms.”
He thus falls into his own reductionist trap. The environment no more produces complex systems than horse hair and cat gut produce string concertos.
The physiological implications of relying upon a multi-oscillator system are particularly evident in birds. The avian time-keeping system is the product of the dynamic interplay between anatomically distinct pace-maker components. The flexibility in the interaction is particularly important in helping the circadian system cope with extreme environmental conditions such as those experienced by high-Arctic (low-amplitude light variations in midsummer) or migratory (travel between time zones) birds.
----the conferees were not “surprised to also find complexity in biological timing mechanisms, considering that they have evolved in response to a complex environment (which we fail to reproduce in our simple artificial laboratory conditions) …. Their contribution brings into focus once again the notion, held all along by the honouree of the conference, that complex environments will necessarily breed complex timing mechanisms.”
He thus falls into his own reductionist trap. The environment no more produces complex systems than horse hair and cat gut produce string concertos.
Q: How could rocks, air and sunlight produce complex biological clocks?
Q: How could they invent timing mechanisms that allow birds to migrate by the stars and the earth’s magnetic field, and to compensate for solar angle and changing seasonal light, and find their breeding grounds unerringly after thousands of miles of flight? The complex parts of the biological clocks reside in multiple organs and genes, which communicate with each other through feedback loops and compensation techniques.
The systems baffle the researchers who try to study them, yet we are.jpg)
told to believe that time, chance and aimless processes of natural selection produced these wonders.
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Q: Which is more amazing: the clocks, or the evolutionists who attribute them to a blind watchmaker?"
CEH
