warm. As a result of this particular creation, heat trans-
mission from these spots, which warm up quickly, to other
parts of the body is facilitated since the distance that needs to be cov-
ered to transmit heat is shortened.
Another butterfly species employs a similar method to increase its body
temperature. You all know what a lens is. Some are used to produce en-
larged images whereas some others are used to produce smaller images of
objects. For example glasses consist of a pair of lenses. Beside this function,
a lens angled correctly toward the sun can concentrate the sun's rays on a
certain spot. Using this method it is possible even to light a fire. The pieris,
another butterfly species, angles its wings toward the sun so that all rays
are concentrated on certain parts of its body that most need to be warm,
in a similar way as a lens functions.
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W O N D E R F U L C R E A T U R E S
