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From:
Stan Sandler <[log in to unmask]>
Reply To:
Informed Discussion of Beekeeping Issues and Bee Biology <[log in to unmask]>
Date:
Tue, 5 Mar 2002 10:32:36 -0500
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Adrian Wenner wrote:

>    In 1946 (SCIENTIFIC AMERICAN), von Frisch echoed that sentiment:
>
>The brain of a bee is the size of a grass seed and is not made for
>thinking.  The actions of bees are mainly governed by instinct. ..."

This quote intrigued me.  I did not contribute to the discussion, because
consciousness is a rather esoteric concept for me (I think therefore I
am?????).  However,  "learning ability"  in the bee (which IMHO has some
relation to "intelligence" at least in relation to how we test
intelligence) has long fascinated me,  and I wondered how von Frisch could
be so dismissive of this, especially in light of the fact that he had
conducted so many experiments which involved bee
learning/conditioning.  Did he not marvel that a brain the size of a grass
seed could "learn" a maze in only six times longer than a rat? (this was
NOT one of his experiments.)

So, I went back and reread the chapter called the "The Bee's Mental
Capacity" in von Frisch's book "The Dancing Bees".  In my view he uses a
rather restrictive view of intelligence:

"We speak of an intelligent action when someone responds in an appropriate
way to a situation that is completely new to him,  making use, in the
process, of some earlier experience.  The prerequisites for such an action
are:  first, a good memory for events of the past, secondly a grasp of the
situation in hand, and finally the ability of mentally associating them"

He gives the bees good marks for memory and the ability to form mental
associations but faults them because:

"Even in our training experiments the bees failed to respond whenever the
task set them differed slightly from those they had been accustomed to
perform in the course of their flower visits which must have been carried
out throughout a period of hundred of thousands of years".

I am not certain how instinct and running a maze are connected.  It seems
to me that one could argue that foraging is like "navigating a maze", but
one could also argue that it is a novel experience for a bee, and that the
problems which are offered to persons taking an "intelligence test" are not
that dissimilar.

In rereading the book, I did come on what I believe is a surprising and
related error that von Frisch made.  In the chapter on drones, (chapter
six) he says in the first paragraph:

"The brain of the drone is smaller than that of both worker and queen -- we
are not left in any doubt as to the intellectual inferiority of the male in
this case."

The following is a comparison of apis mellifera from Comprehensive Insect
Physiology , Biochemistry and Pharmacology, Vol 5, by Kerkut and Gilbert,
Pergamon Press, 1985 page 307:

                                       worker
drone

total brain volume        1.321  mm cubed                7.839 mm cubed

neuropil volume           1.07 mm3 (81%)                 7.286 mm3 (93%)

mushroom bodies        0.131 mm3 (12%)               0.098 mm3 (1.34%)

central body                0.004 mm3 (0.37%)            0.0033 mm3 (0.045%)

protocerebral bridge     0.0001 mm3 (0.01%)           0.0005 mm3 (0.006%)

optic lobes                  0.5634 mm3 (52.65%)          6.663 mm3 (91.45%)

antennal lobes             0.03 mm3 (2.8%)                 0.067 mm3 (0.91%)

total # neurons             851,000                               1,209,000

neuropil volume as % of brain volume; all others as % of neuropil volume

To those figures I would add these from Hive and Honeybee:

"It has been estimated that there are 5 or 6 thousand plate organs on the
antennal flagella in the worker, 2 or 3 thousand in the queen and perhaps
30 thousand in the drone."

So, to go back to von Frisch's dismissal of the intellectual capacity of
the drone, it seems as if in terms of brain volume and neuropil volume the
drone is vastly better endowed than the worker (by a factor of six or
seven); and in terms of total no of neurons it has 50% more.  I think we
also could infer that its eyesight is likely much better (larger eyes, huge
difference in optic lobes) and so is the sense of smell (five times more
plate organs, twice as large antennal lobe).  The central body and the
mushroom body are smaller and the percentages are vastly smaller.  Are
these the places where all the instincts for those marvellous tasks which
only the WORKER bees perform lie?  But von Frisch says these are not
intelligent tasks..... So, it is possible that with a much larger brain and
neural and sensory capacity and a head empty of many instincts (except for
a keen s*x drive) that the indolent, roaming drones are the real epicures
and philosophers of the hive  ; )   I did not notice many contributions
from sourthern hemisphere beekeepers and female beekeepers to the thread on
bee consciousness.  They were probably too busy working.  And von Frisch
may have been unable to transcend his protestant work ethic in his comments
on drones.

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