THE MENTAL LIFE OF FISHES
33 5
came and rubbed their months on the hand with the'smell
of food on it, but paid no attention to the other.
As a matter of fact, the simile is only useful for the
simplest kind of reex action, but its attempted use helps us
to appreciate the wonderful powersof co—ordinati0n between
and muscles, evenin a sh. How this co-ordination
may have arisen is a, question that should be considered,
even'if briey.- -
-
,
According to Darwin, instincts are to be regarded in the
same
light as other characters; they depend upon some
—
inherited modication of the brain.- Their usefiness is a
sufcient explanation of their existence. Since instincts
vary, their origin may be referred to a natural selection of
_
the better with an elimination of the worse.
Darwin did
not deny the possibility of intelligence taking a part in form— -
‘
ing an instinct or habit which could be
as the fear acquired by birds on uninhabited islands after
man had come amongst them—but he considered that the
great majority came from the natural ‘ selection [of small
variations of unknOWn:originior “cause. . Weismann carried
'
—
this
:an'd —cut=out the intelligence and
acquiredl—inheritance:= altogether; all instincts arise‘ from
_
"
The
in the way of accepting' the selecti0n '
.
fhèQrÿ,‘aSa eXplanation'of the phenomena Of dier'entiation
sh‘es have been discussed in previous chapters. ‘The
—
same difcülties are met with here.
Some of the Threespined Sticklebacks, for example, do not build nestS, others
do ; who can say which is the more useful instinct?
Weis—
—
mann’s endeavour° to derive characters useful to the adult
from variations in the germplasm—though a logical conclu—‘
,
sionfrom_Darwin’s position—shows, indeed, the inadeqùaéy
'
of thédoctrine of utility.
:
_,
'. .“
_
Both Darwin and Weismann have taken a very'restricted
view of the inheritance of
'
; j
'
.
thereunder only "the
and instincts.
ï
.
:
From the past history Of shes, however, we know that Whole «
have been
out _at various
The
.,
_
33 5
came and rubbed their months on the hand with the'smell
of food on it, but paid no attention to the other.
As a matter of fact, the simile is only useful for the
simplest kind of reex action, but its attempted use helps us
to appreciate the wonderful powersof co—ordinati0n between
and muscles, evenin a sh. How this co-ordination
may have arisen is a, question that should be considered,
even'if briey.- -
-
,
According to Darwin, instincts are to be regarded in the
same
light as other characters; they depend upon some
—
inherited modication of the brain.- Their usefiness is a
sufcient explanation of their existence. Since instincts
vary, their origin may be referred to a natural selection of
_
the better with an elimination of the worse.
Darwin did
not deny the possibility of intelligence taking a part in form— -
‘
ing an instinct or habit which could be
as the fear acquired by birds on uninhabited islands after
man had come amongst them—but he considered that the
great majority came from the natural ‘ selection [of small
variations of unknOWn:originior “cause. . Weismann carried
'
—
this
:an'd —cut=out the intelligence and
acquiredl—inheritance:= altogether; all instincts arise‘ from
_
"
The
in the way of accepting' the selecti0n '
.
fhèQrÿ,‘aSa eXplanation'of the phenomena Of dier'entiation
sh‘es have been discussed in previous chapters. ‘The
—
same difcülties are met with here.
Some of the Threespined Sticklebacks, for example, do not build nestS, others
do ; who can say which is the more useful instinct?
Weis—
—
mann’s endeavour° to derive characters useful to the adult
from variations in the germplasm—though a logical conclu—‘
,
sionfrom_Darwin’s position—shows, indeed, the inadeqùaéy
'
of thédoctrine of utility.
:
_,
'. .“
_
Both Darwin and Weismann have taken a very'restricted
view of the inheritance of
'
; j
'
.
thereunder only "the
and instincts.
ï
.
:
From the past history Of shes, however, we know that Whole «
have been
out _at various
The
.,
_