The Darkest Hour…

“…The Darkest Hour is Just Before Dawn…”   Thomas Fuller

For those of us “late-risers,” getting up to measure how ‘dark it is before dawn,’ isn’t going to happen.  In actuality, this phrase first appeared in print during the late 1700s and is attributed to the English theologian and historian, Thomas Fuller.  It has been used more as a teaching proverb meaning, ‘There is hope, even in the worst of circumstances’, not the gradation of the night sky.  Whether it is day or night, most animals have daily cycles of activity known as circadian rhythms. For example, roosters have a very vocal way of expressing the coming of a new day – crowing.

Roosters anticipate sunrise to get a head start on their daily hunt for food and defense of territory. Now, a new study shows that roosters don’t need the light of a new day to know when it’s dawn—rather, their internal clocks alert them to the time.  Like all birds, roosters sing – or crow – in a daily cycle. But if one rooster in the neighborhood has an internal clock that’s set a little early, he can stimulate other roosters to crow early, too. Humans have a similar clock.  This time of year it is the neighbor revving up their lawnmower at the crack of dawn. Which causes all the night owls to take part in this territorial fight. The early bird might get the worm or shorter grass, but not for long.

A new brain-scan study has shown that early birds might be singing loud and clear first thing in the morning, but mentally wear out faster.  On the flip side of the pillow, night owls stay alert longer than their early bird friends.  As part of the study, scientists measured levels of melatonin, a hormone thought to help naturally regulate sleep cycles in night owls and early risers.  It was discovered an hour and a half after waking, both subject groups scored the same on tasks involving attention to detail.  It gets interesting as the day wears on.  The morning group showed reduced activity in the brain areas linked to attention compared to the night group.  Results found that people tend to favor mornings or nights based at least in part on how they react to a kind of competition in the brain. Circadian hormones, which keep us alert while awake, can get overridden by sleep pressure, a physiological pull that causes us to get sleepier the longer we’re awake. So, whether you’re up at first light to seize the day or wait for the day to begin at last light, it’s only time and we all get the same 24 hours.