overcome the effects of a stressful or toxic environment so that certain
genes do not become activated? We may not be able to control all the
conditions in our external environment, but we certainly have a choice in
controlling our inner environment.
Genes: Memories of the Past Environment
To explain how we can control our inner environment, I need to talk a bit
about the nature of genes, which are expressed in the body when cells
manufacture specific proteins, the building blocks of life.
The body is a protein-producing factory. Muscle cells make muscle
proteins that are called actin and myosin, skin cells make skin proteins
called collagen and elastin, and stomach cells make stomach proteins called
enzymes. Most of the cells of the body make proteins, and genes are the
way we make them. We express particular genes via certain cells making
particular proteins.
The way most organisms adapt to conditions in their environment is
through gradual genetic modifications. For example, when an organism is
faced with tough environmental conditions such as temperature extremes,
dangerous predators, fast prey, destructive winds, strong currents, and so
on, it is forced to overcome the adverse aspects of its world in order to
survive. As organisms record those experiences, in the wiring in their brains
and the emotions in their bodies, they will change over time. If lions are
chasing prey that can outrun them, then by actively engaging the same
experiences for generations, they will develop longer legs, sharper teeth, or
bigger hearts. All of these changes are the result of genes making proteins
that modify the body to adapt to its environment.
Let’s stay with the animal world to look at how this works in terms of
adaptation or evolution. A hypothetical group of mammals migrated to an
environment in which the temperature ranged from -15 to 40 degrees
Fahrenheit. The genes in those mammals, over many generations of living
under extremely cold conditions, would eventually be triggered to produce
a new protein, which would produce thicker and greater amounts of fur
(hair and fur are proteins).