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death. She offers a carnivore the options of dying by starvation or of
killing for a meal.
Nature is like a sculptor continually improving upon her work,
but to do it she chisels away at living flesh. What's worse, she has built
her morally reprehensible modus operandi into our physiology. If you
occasionally feel that you are of several minds on one subject, you are
probably right. In reality, you have several brains. And those brains
don't always agree. Dr. Paul D. MacLean was the researcher who first
posited the concept of "the triune brain." According to MacLean, near
the base of your skull you'll find the stem of the brain, poking up from
the spinal column like the unadorned end of a walking stick. Sitting
atop that rudimentary stump is a mass of cerebral tissue bequeathed us
by our earliest totally land-dwelling ancestors--the reptiles.8 When
these beasts turned their backs on the sea roughly 300 million years ago
and hobbled inland, their primary focus was simple survival. The new
landlubbers needed to hunt, to find a mate, to carve out territory and
to fight in that territory's defense. The neural machinery they evolved
took care of these elementary functions. MacLean calls it the reptile
brain. The reptile brain still sits inside our skull like the pit at the
center of a peach. It is a vigorous participant in our mental affairs,
pumping its primitive, instinctual orders to us at all hours of the day
and night.
Eons after the first reptiles ambled away from the beach, their
great, great grandchildren many times removed evolved a few
dramatic product improvements. These upgrades included fur, warm
blood, the ability to nurture eggs inside their own bodies, and the
portable supply of baby food we know as milk. The remodeled
creatures were no longer reptiles. They had become mammals.
Mammals' innovative features gave them the ability to leave the lush
tropics and make their way into the chilly north. Their warm blood
allowed them, in fact, to survive the rigors of the occasional ice age.
But warm blood exacted its costs. It demanded that mammal parents
not simply lay an egg and wander off. It forced mammal mothers to
brood over their children for years. And it required a tighter social
iverse. She presents her children with a choice between death and
<< < GO > >>
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4
un
death. She offers a carnivore the options of dying by starvation or of
killing for a meal.
Nature is like a sculptor continually improving upon her work,
but to do it she chisels away at living flesh. What's worse, she has built
her morally reprehensible modus operandi into our physiology. If you
occasionally feel that you are of several minds on one subject, you are
probably right. In reality, you have several brains. And those brains
don't always agree. Dr. Paul D. MacLean was the researcher who first
posited the concept of "the triune brain." According to MacLean, near
the base of your skull you'll find the stem of the brain, poking up from
the spinal column like the unadorned end of a walking stick. Sitting
atop that rudimentary stump is a mass of cerebral tissue bequeathed us
by our earliest totally land-dwelling ancestors--the reptiles.8 When
these beasts turned their backs on the sea roughly 300 million years ago
and hobbled inland, their primary focus was simple survival. The new
landlubbers needed to hunt, to find a mate, to carve out territory and
to fight in that territory's defense. The neural machinery they evolved
took care of these elementary functions. MacLean calls it the reptile
brain. The reptile brain still sits inside our skull like the pit at the
center of a peach. It is a vigorous participant in our mental affairs,
pumping its primitive, instinctual orders to us at all hours of the day
and night.
Eons after the first reptiles ambled away from the beach, their
great, great grandchildren many times removed evolved a few
dramatic product improvements. These upgrades included fur, warm
blood, the ability to nurture eggs inside their own bodies, and the
portable supply of baby food we know as milk. The remodeled
creatures were no longer reptiles. They had become mammals.
Mammals' innovative features gave them the ability to leave the lush
tropics and make their way into the chilly north. Their warm blood
allowed them, in fact, to survive the rigors of the occasional ice age.
But warm blood exacted its costs. It demanded that mammal parents
not simply lay an egg and wander off. It forced mammal mothers to
brood over their children for years. And it required a tighter social
iverse. She presents her children with a choice between death and
<< < GO > >>