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Re: Extinction and other...
ah but don't look at humans, WE didn't survive the KT....our ancestor 65
million years ago did. WE are derived.
As I've been trying to nail down details, the pineal gland seems to keep
track of the light vs dark periods, so dimmer light vs brighter light is
not as appplicable to it's function as day length vs night length.
Unless the earth's been knocked off it's orbit to screw up the seasons,
and out of normal rotation to screw up day/night, these periods would
not have changed.
Matt Wedel wrote:
> > So far in my lax investigations, late Cretaceous dinosaurs did not seem
> > to have the conformation of the skull that would allow light in to be
> > measured by the pineal gland.
> Neither do we. The pineal gland is deep in our heads; the only light it
> "measures" is that which comes in through our eyes. Melatonin release by
> the pineal gland appears to be correlated with seasonal variations in light,
> but the pineal gland does not receive light directly. Same for crocs,
> birds, and most dinos, AFAIK.
> Furthermore, if the dust cloud was dense enough to supress or suspend
> photosynthesis, the pineal glands in all of these organisms would not be
> picking up normal amounts of light. I suspect that, based on the reduced
> light, most organisms' pineal glands would think it was midwinter, or dusk,
> or whatever, all the time, and alter their melatonin release accordingly,
> for the duration.
> Seasonal Affective Disorder killed the dinosaurs.
Flying Goat Graphics
(Society of Vertebrate Paleontology member)