Page 226 - The Error of the Evolution of Species

The Error of the Evolution
of Species

Industrial-Revolution Moths' True Resting Place

The species Biston betularia used in researches has a
feature of close interest to our subject matter here. These
moths are nocturnal; they are active during the night hours

and rest during the day, returning to their resting places be-
fore sunrise—before they can be hunted down by birds—
and remain there, motionless, for the rest of the day.
In Kettlewell's experiments, the moths were released in
the morning—that is, in daylight—and were observed
throughout the day. At night they were recaptured, so that
the research was carried out at times incompatible with the
moths' lifestyle. Kettlewell was actually aware of this, but
maintained that this would not affect the results of his ex-

periment. 291
In fact, however, Kettlewell's assumption was too great
an error to be overlooked. Daylight caused the moths to be-
come confused and lose their way, and thus to land on trees
that would make them easy prey for birds. And in fact, the
species B. betularia actually does not spend its days resting
on tree trunks at all. The idea that these insects do is an er-

ror going back some 20 years.
In the early 1980s, research by Kauri Mikkola from
Helsinki University into caged Biston betularia moths first

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