In Exodus chapter eight, God brought upon the
Egyptians "swarms of flies" to convince Pharaoh to release
the children of Israel. The huge number of flies must have been
an amazing thing to see. Yet, in the flight of a single fly, scientists
discover amazing abilities built into the muscles of the fly by
the Great Designer when He created it. Let us look at what they
have discovered and see how we might understand better how our
own bodies might work.
The ability of flying insects to beat their wings
at amazing speeds to produce flight leaves engineers and scientists
wondering how signals can be sent from the brain to the muscles
fast enough to control flight. As Tom Irving of the Illinois Institute
of Technology says, "For an insect, it is too difficult to
have an electrical signal go from the brain to the muscle 200
times per second." This is the speed of the nerve signals
if each beat of the wing of a fly were to be controlled separately.
Instead, they have found in the muscles of the fly a mechanism
that prevents the need for separate signals to control the muscle
contractions. It is called "stretch activation" and
involves one set of muscles automatically firing a contraction
when its opposing set of muscles causes it to stretch. This contraction
of one muscle after its opposite has contracted allows the muscles
of the wings of the fly to move without a nerve signal from the
brain. This is called an "internal feedback loop" and
presents at least one problem. How does it turn off? Well, that
is a good question and, as quoted by Live Science writer
Michael Schirber in the Animal Domain section of the Live Science
website, Tom Irvine says, "I'm not sure how it turns off."
When we are talking about these kinds of incredible
speeds, it is truly amazing that insect flight happens at all!
The common honeybee beats its wings at about 240 times per second;
the fruit fly is a little slower at 200 times per second; but
they cannot hold a candle to the male mosquito who beats its wings
at 450 to 600 times per second. Still, that is almost a snails'
pace when compared to the world's record holder, the "no-see-ums"
or midges, which beat their hairy wings at more than 1,040 beats
per second!
Besides the flight muscles which are housed in
the thorax that produce lift, the insects also have at least 13
smaller muscles that are used to control all of the other aspects
of flight. These muscles include those that control the basic
principles of flight, like roll, pitch, and yaw. So, God has designed
the flight ability of the insects with truly amazing complexity.
Scientists continue to study insect flight with
ever-advancing technology, such as X-ray beams a million times
more intense than those used for imaging the human body; but,
at these intensities, it would only take a second to kill the
insect they are studying. So, they have found that .03 millisecond
exposures are necessary to get the pictures they need, but they
need to get at least 150 of these short exposures. Creative scientists
have learned how to tether flies in a way that they think they
are flying when in reality they are just beating their wings and
going nowhere. This allows a stationary target for the X-ray beams
to get the pictures of the muscle fibers as they beat at these
astronomical speeds.
Further study needs to be done in order to understand
this simplest of God's creations, and, then, to see if we can
learn how the human heart muscle beats, which happens in a similar
"no signal" from the brain type of method. Let us praise
the Creator each day as we watch his creations around us! -Rt.
1 Box 116A, Belington, WV 26250. aedeverson@yahoo.com