4. HORMONES AND BEHAVIOR
205
The other side of the coin for investigators of the hormones and
behavior are the problems that are not encountered or, perhaps more
accurately, are encountered in a very different form in studies of such
tissue responses as secretion, growth, muscular contraction, fluid balance,
etc. There is the problem of distinguishing between the hormones which
influence behavior directly and those with actions which are merely
supportive; its counterpart is the behavior which is subject to hormonal
influence. One of the oldest problems, and one that is still very much
with us, centers around the recording and measurement of behavior.
The opinion was once held by many endocrinologists and morphologists,
that the end points of behavior are not sufficiently sharp to be useful in
experimental studies. The dominance of this belief may well have discouraged biochemists from entering this field of investigation. However,
as we show, as the behavior characterizing members of each phylum
is described, the contrary is true; indeed the nature of the end points
has been the means to insights not easily gained from the other responses. Phyletic, generic, species, and even strain differences are the
evidence that an evolution of behavior has occurred, but in the complex
of the relationships we are discussing what has evolved—the endocrine
system producing these hormones or the character of the tissues on
which the hormones act? Other problems are more conventionally
endocrinological: e.g., the identification, nature, and origin of the hormones which influence behavior; the place and manner of action of
these hormones in bringing to expression the behavior with which their
action is associated; and the temporal relationships. The problems mentioned thus far are common to all animals displaying behavior which is
subject to hormonal control. For this reason it seems well to elaborate
on them before turning to a discussion of the many specific relationships
that have been revealed.
II. The Hormones Influencing Behavior and the Behavior
Most Subject to Hormonal Influence and Control
The many relatively recent reviews and discussions of the hormones
and behavior (2-9) have dealt largely with the relationships between
steroid hormones and particularly between the gonadal hormones and
behavior. Other reviews and original articles deal with the hormones
associated with growth and pupation in insects, including their behavior
during metamorphosis (10-15).
Except for the suggestion that the
active principles of the prothoracic gland are unsaturated ketones (16,
17), the chemical nature of the insect hormones is largely unknown.
The subject is discussed briefly in a review which contains a characterization of the prothoracic gland hormone, ecdysone (17a).
205
The other side of the coin for investigators of the hormones and
behavior are the problems that are not encountered or, perhaps more
accurately, are encountered in a very different form in studies of such
tissue responses as secretion, growth, muscular contraction, fluid balance,
etc. There is the problem of distinguishing between the hormones which
influence behavior directly and those with actions which are merely
supportive; its counterpart is the behavior which is subject to hormonal
influence. One of the oldest problems, and one that is still very much
with us, centers around the recording and measurement of behavior.
The opinion was once held by many endocrinologists and morphologists,
that the end points of behavior are not sufficiently sharp to be useful in
experimental studies. The dominance of this belief may well have discouraged biochemists from entering this field of investigation. However,
as we show, as the behavior characterizing members of each phylum
is described, the contrary is true; indeed the nature of the end points
has been the means to insights not easily gained from the other responses. Phyletic, generic, species, and even strain differences are the
evidence that an evolution of behavior has occurred, but in the complex
of the relationships we are discussing what has evolved—the endocrine
system producing these hormones or the character of the tissues on
which the hormones act? Other problems are more conventionally
endocrinological: e.g., the identification, nature, and origin of the hormones which influence behavior; the place and manner of action of
these hormones in bringing to expression the behavior with which their
action is associated; and the temporal relationships. The problems mentioned thus far are common to all animals displaying behavior which is
subject to hormonal control. For this reason it seems well to elaborate
on them before turning to a discussion of the many specific relationships
that have been revealed.
II. The Hormones Influencing Behavior and the Behavior
Most Subject to Hormonal Influence and Control
The many relatively recent reviews and discussions of the hormones
and behavior (2-9) have dealt largely with the relationships between
steroid hormones and particularly between the gonadal hormones and
behavior. Other reviews and original articles deal with the hormones
associated with growth and pupation in insects, including their behavior
during metamorphosis (10-15).
Except for the suggestion that the
active principles of the prothoracic gland are unsaturated ketones (16,
17), the chemical nature of the insect hormones is largely unknown.
The subject is discussed briefly in a review which contains a characterization of the prothoracic gland hormone, ecdysone (17a).