From: viking@iastate.edu (Dan Sorenson)
Subject: Re: Self Regulating Populations
Organization: Iowa State University, Ames IA
Date: Fri, 4 Sep 1992 04:12:34 GMT

In <Bu0nDp.Cws@wpg.com> russ@wpg.com (Russell Lawrence) writes:

>From viking@iastate.edu (Dan Sorenson):
>ds> There's nothing esoteric about it.  Gunfire and thunder sound
>ds> different, and once thunder is shown to not be a threat there is no
>ds> reason a different sound needs to be thought of as unthreatening. 

>A previous poster declared that deer would know that a gunshot is 
>dangerous by virtue of the fact that a missed shot would kick up 
>dust and debris.  Assuming that a deer had the opportunity of 
>surviving a lot of missed shots, how would this differ from the 
>dust and debris and tree rustling caused by thunder storms?  

	About the same way an Oaklahoma dust storm differs from the
little Dust Devil commonly seen on gravel roads or open fields.  The
previous poster is right, but the scope is limited.  My example of
missing birds and their flying away should show this.  In addition,
hunters don't tend to be in the woods during thunder storms, nor does
ozone smell like humans, and I submit the two conditions are even
further apart than in sound alone.

>As far as I can tell, the only way a deer might know that 
>gunshots cause harm is if he, himself, were shot and managed to 
>connect the sound with the pain, or, if he were able to observe
>the death of another deer at close proximity.   Do you think
>that either of these scenarios is sufficiently likely that we
>can rightly judge the "stupidity" of dead deer on the basis of the
>assumption that they had failed to learn from prior experience?

	I don't think either is sufficiently valid, to tell the truth.
I'd bet chickens are naturally afraid of foxes and badgers, yet it is
ludicrous to think they would have to be chased and/or hurt by such
a beast to determine it is a threat.  You're stretching yourself
pretty thin on this one.

>ds> That other members are killed during this sound is merely 
>ds> reinforcement.

>Is there much evidence to indicate that the death of one member of
>the herd is going to be well-known by other members of the herd?
>How close would another deer have to be in order to observe such
>an event?

	Given the eyesight of a deer, a mile of open land is good enough.
Woods will lower this a bit, but the smell of blood should carry for
several hundred feet.

>   Why should we assume that one deer would have the 
>linguistic ability to pass this info along to other deer?

	Again, you assume a need for verbal communication and a language.
This is unnecessary.  Police cars do not hail you over a loudspeaker and
tell you to get off the road, and likewise deer need no such distinct
verbage to communicate.  Why else do game calls work?

>rl> ... I suppose we could test your theory by playing back 
>rl> sounds of thunder, firecrackers, loud music, and so on, to see if 
>rl> deer really do understand the significance of gunfire.  It may be 
>rl> the case that they do understand the significance, but I haven't 
>rl> seen any convincing evidence to support the claim.

>ds> I suspect your needs for proof here are slighly greater than they 
>ds> would be for other aspects of animal behavior.  Tell me, do your 
>ds> dogs salivate at the sound of the dog food bag being rustled?  If 
>ds> so, do they salivate (or come running, take your pick) when you 
>ds> fold the newspaper?  It's the same sound of paper rustling, yet 
>ds> you cannot use this as proof that animals can distinguish between 
>ds> similar sounds and determine the ramifications of each based on 
>ds> default survival instinct and experience?  

>The nature of the learning experiences between feeding dogs and
>killing deer are enormous.  It's not "survival instinct" that causes
>a dog to come running when he hears noises in the kitchen;  
>rather, it's the result of day-in-day-out experience that teaches 
>him what these sounds usually signify.

	Right...  What's the use of a "watchdog" if it can't distinguish
between you rolling over in bed and the front door swishing against
the carpet as it's slowly pushed open?  Survival instinct may not cause
the dog to salivate, but that instinct would respond to stimulai from the
same senses, and my example shows dogs are capable of distinguishing
between two subtly different sounds and reacting differently.  That the
reaction wasn't based on survival is secondary to the proof.

>  If we were to give a 
>dozen dogs the opportunity to learn to come running at such 
>sounds, and then kill them one-by-one in relative isolation from 
>one another, do you think the remaining dogs would learn from the 
>experience, and run away at the sound of kitchen noises?   

	Do it with those dogs within hearing distance, or even within
smelling distance, and you had best bet on it.  I note that the common
perception of calves being terrified upon entering the slaughterhouse
is entirely voided if you claim this proof, as direct observation of
the killing floor is not possible from outside the floor in most cases.

>Evolutionary development requires many, many generations to manifest
>itself, Dan.  I have no doubt that evolution has helped deer to
>defend themselves from four-legged predators, but there's no reason
>to believe that it's been effective in helping deer to recognize
>the significance of gunfire and unseen bullets.

	Evolution doesn't help them at all, even against other four-
legged animals, save to give them sufficient sensory perception and
suitable weapons for defense to ensure a good shot at survival.  That
the predator now strikes from 50 yards instead of five is no reason
to assume evolution is necessary to help the prey survive.

>   As I've pointed
>out repeatedly, the wolf experts claim that the courage to stand
>and defy small predators, like wolves, is more advantageous than
>the fear that would cause an animal to run away.  Yet, you seem
>to be saying that "courage" is "stupidity" since the "smart" deer
>are supposed to know about guns.

	Against different threats, stupid and couragous can indeed
be the same act.  It is couragous to charge a badger while screaming.
Against a black bear, it's stupid.  You'll note that both of these
animals are predators, but of unequal threat to us.

<Dan Sorenson, DoD #1066 |"There'll be angels on Ariels in leather>
<z1dan@exnet.iastate.edu | and chrome, Ridin' down from heaven    >
<viking@iastate.edu      | just to carry me home." -- R. Thompson >
< ISU thinks I need more education, which they provide for a fee. >