Bull Trout

Jonathan Cook wrote (about lions and tigers):

I'd be glad to declare them subspecies -- like cutts
are to rainbows, but I see no concrete scientific reason to say
they are true species.

Your case would be stronger if cutts and rainbows weren't themselves
true species g

The truth is in the middle. Species are "real," but pinning them down with
a simple definition is hard.

Ahh, but we have concrete and objective definitions, don't we?

Yes, but not necessarily simple ones. It's no more than a preconceived
notion (based vaguely perhaps on a common catch-all illustrative
simplification previously used in junior-high science classes) that the
definition of species has to be one that is simply stated and
intuitively obvious. I've had lots of lengthy discussions with folks
over the concept of "species" (or, to refer to another current thread
here, on the pros and cons of hatchery policies in the PNW), only to
have the other person say at some point, "oh, well, you know, I don't
believe in evolution," as though one could have an opinion worth
listening to about either subject without at least a basic understanding
of evolution.

Fortunately, the definition of "species" isn't left to armchair
taxonomists.

As Darwin wrote to Joseph Hooker: "How painfully true is your remark that
no one has hardly the right to examine the question of species who has not
minutely described many."

Ahh yes, we must uphold the high priesthood of rationalism, the
ivory tower scientists. Us laity just can't grasp the reasoning
it takes to distinguish species. We should just blindy follow
and believe our priests, and if we did the world would be a much
better place. Everything they say is true -- how dare we question
it. If we do, they'll just laugh and call our ideas absurd, or
tell us not to try to be armchair priests.

This article by Ernst Mayr is very useful reading (and may be where
Steve found his references to "armchair taxonomists" and Darwin's
correspondence with Hooker):

http://members.aol.com/darwinpage/mayrspecies.htm

JR

"Willi" wrote in message
...


Jonathan Cook wrote:

rw wrote in message
...

On 2004-02-06 15:21:48 -0700, (Jonathan Cook) said:


Lions and tigers have been bred and produced fertile offspring. Would
you
call them one species?


Assuming fertile offspring is the norm between the two, yes.

If biologists were consistent in applying their own "rules" about
what constitutes a species, such as physical, geographic, or
behavioral isolation, then we ought to have a multitude of human
species, and a multitude of dog species, and plenty of other
examples. The current use of these rules is "soft science" and
it bothers me.

Lately it seems like the readiness to declare new species is also
founded on political reasons -- mainly to bring the endangered
species act into play and "preserve" the environment. In NM we have
the Rio Grande silvery minnow, a very endangered species. Well we
had a state biologist talk at our FF club and I learned that there's
a Pecos river silvery minnow that is not endangered and that can
only be distinguished from the RG minnow by a delicate autopsy
and inspection of the vertabrae at the base of the skull. When I
asked why it is considered a different species, I was basically
talked down to as if I didn't understand science and no
reasonable person would even think that (they *are* geographically
isolated and have been for a while).


I used to accept your definition because it seemed to make the most
sense and seemed concrete and absolute. However, through reading and
thinking about it, I've come to the conclusion that it is as arbitrary
as any other definition. There are problems with any definition of a
species. Any definition of "species" is just an attempt to choose a
specific point on a continuum.

Although your definition may seem concrete on the surface, it too is
arbitrary and depends on your definition of "bred" and "fertile" and
when man's intervention is thrown into the mix, things get even more
complex.

With your definition, some of the choices that need to be made include:


Animals that will occasionally breed naturally in the wild

Animals that would breed naturally in the wild but never come into
contact because of physical barriers

Animals that could breed naturally in the wild but don't because of
behavioral differences

Animals that will breed only when confined together in captivity who in
the wild have contact but choose not to interact

Animals that will breed in captivity only when treated with hormones or
other types of manipulation

Animals that won't breed but will have fertile offspring through simple
artificial insemination

Animals that won't breed but will have fertile offspring through
artificial insemination with physical changes made such as a change in PH

Then we get into genetic manipulation

As man makes more technological advances, more and more levels will be
introduced that will need to be considered.

How the definition is to be used adds even more complexity. Is it being
used to describe the evolutionary process, explain genetic differences,
for political reason, etc.

Plants......you forgot about plants. How about an apple trunk grafted onto
pear rootstock and later augmented with plum and cherry branches? (It's
doable.....they're all Rosaceae and graft relatively easily.)

And then, there is the rather knotty problem of asexual reproduction. Any
definition that depends on the successful mating of a pair of individuals
resulting in fertile offspring sort of leaves yeasts, for example, out in
limbo. If no two of the saccharomyces cavorting in my bread dough ever get
together to do the nasty, is every one of them a different species?

And what about bacteria that simply grab a chunk of DNA from some host and
make it their own? Looks to me like any one of them may actually be two or
more species based on genetic evidence.

Any recognized species of lichen IS two species, and of different kingdoms
at that.

Viruses. Viruses don't have ANY DNA of their own.

Species are a fiction. They can be very useful fictions, but the uses to
which they are put are not always noble or even justifiable.

The vast majority of species on the planet fail to conform nicely to the
traditionally accepted definition.

Wolfgang
mitochondria, anyone?

Wolfgang wrote:


Plants......you forgot about plants.


I sure did, how animalcentric of me!

That muddies up the fertile offspring definition even more!

Willi

On 2004-02-07 11:32:40 -0700, "Wolfgang" said:

Viruses. Viruses don't have ANY DNA of their own.

Wrong. Retroviruses only have RNA, but typical viruses have DNA.

Species are a fiction.
They can be very useful fictions, but the uses to
which they are put are not always noble or even justifiable.

If I get caught keeping a Cutthroat Trout where I'm only allowed to take
Brook Trout, or shooting an elk when I only have a deer tag, I'll use the
Wolfgang Defense -- species are a fiction! :-)

-----------------------------------------------------
Cut "to the chase" for my email address.

"rw" wrote in message
. ..
On 2004-02-07 11:32:40 -0700, "Wolfgang" said:

Viruses. Viruses don't have ANY DNA of their own.

Wrong. Retroviruses only have RNA, but typical viruses have DNA.

Typical?

Species are a fiction.
They can be very useful fictions, but the uses to
which they are put are not always noble or even justifiable.

If I get caught keeping a Cutthroat Trout where I'm only allowed to take
Brook Trout, or shooting an elk when I only have a deer tag, I'll use the
Wolfgang Defense -- species are a fiction! :-)

If you get busted keeping cutthroat where only brookies may legally be kept
or shooting elk without a proper license being a snot isn't likely to keep
you from paying a hefty fine and/or going to jail. This is as it should be.

There is no "Wolfgang Defense". I have never needed to defend myself
against a charge of poaching. Trying to avoid dealing with the consequences
of your actions by stating that species are a fiction is likely to have the
same effect as similar efforts do here. That is to say, it won't work.
Eventually you are going to get caught and you WILL have to pay.

Still, when the judge asks whether you understood the regulations, you might
want to try telling him that you don't read that tripe.

Wolfgang
just like you didn't read this.

"Wolfgang" wrote in message ...

[Willi wrote:]

With your definition, some of the choices that need to be made include:

Actually, those are the exact choices I'm trying to take _out_
of the definition.

Plants......you forgot about plants. How about an apple trunk grafted onto
pear rootstock and later augmented with plum and cherry branches? (It's
doable.....they're all Rosaceae and graft relatively easily.)

Sorry, you'd have to come up with a better example. Grafting has nothing
to do with reproduction. Can apple tree pollen fertilize pear tree
blossoms? I don't know much about plants, but I doubt it. Doctors have
experimented with pig organs in humans, but that doesn't make us the
same species. (although certain individuals might make us think so :-)

As far as single-celled organisms at the varying complexity levels go,
I don't know enough to comment.

Species are a fiction. They can be very useful fictions, but the uses to
which they are put are not always noble or even justifiable.

I think _that's_ something I can agree with.

Jon.

"Jonathan Cook" wrote in message
m...
"Wolfgang" wrote in message
...

[Willi wrote:]

With your definition, some of the choices that need to be made
include:

Actually, those are the exact choices I'm trying to take _out_
of the definition.

I think the fundamental problem with the definition of species is that pesky
little definite article, "the". Various definitions are extremely useful to
more or less worthless depending on circumstance.

Plants......you forgot about plants. How about an apple trunk grafted
onto
pear rootstock and later augmented with plum and cherry branches? (It's
doable.....they're all Rosaceae and graft relatively easily.)

Sorry, you'd have to come up with a better example. Grafting has nothing
to do with reproduction. Can apple tree pollen fertilize pear tree
blossoms? I don't know much about plants, but I doubt it. Doctors have
experimented with pig organs in humans, but that doesn't make us the
same species. (although certain individuals might make us think so :-)

Well, I wasn't so much trying to come up with an example as provide an
obviously absurd end point on a spectrum. Though, actually, with a bit of
thought one should be able to see that it really isn't as absurd as it might
appear at first glance. "Can apple pollen fertilize pear tree blossoms?" I
doubt it too. However I'm not certain. There are a couple of things that
make the question interesting. For one thing, both apples and pears have
long been the objects of careful selection. Importantly, this selection is,
by and large, NOT the sort of selective breeding generally conceeded to
mirror natural selection and which, not so incidentally, played an important
role the evolution of Darwin's theories. The thousands of popular varieties
of apples (and, to a lesser extent, pears) developed over the centuries are
mostly a result of selecting a particular fruit and then grafting the stem
it grew on to a larger supportive structure.....vegetative reproduction, as
opposed to genetic recombination via sex. It is a well known (and mostly
true) maxim that if you plant seeds from your favorite apple you end up with
a tree that produces mostly crab apples, or something very similar. The
same is, of course, true for the other popular fruits in the Rose family.
So, what does the prototypical pear look like? Well, despite thousand of
years of selection, the similarities between apples and pears are still
readily apparent. I'd guess that it looks a lot like the prototypical
apple. Could two distinct (if closely related) species of grass cross-breed
and produce corn? Hm.......nah, probably not.

As far as single-celled organisms at the varying complexity levels go,
I don't know enough to comment.

Varying levels of complexity? Well, a paramecium is certainly anatomically
more complex than a cyanobacterium....um, at the level of the limits of
light microscopy, anyway....but it's a mistake to think that complexity on
that level necessarily corresponds in a linear fashion to the scale of DNA.

Species are a fiction. They can be very useful fictions, but the uses
to
which they are put are not always noble or even justifiable.

I think _that's_ something I can agree with.

Good. I'd much rather someone agree with the point while rejecting an
illustrative example than vice versa.

Wolfgang

Jonathan Cook wrote:

"Wolfgang" wrote in message ...

[Willi wrote:]


With your definition, some of the choices that need to be made include:


Actually, those are the exact choices I'm trying to take _out_
of the definition.


You may be trying but I don't think you'll succeed. I think I understand
where you're coming from because that's how I used to look at it. But,
IMO, the over simplification of using the criteria of "breed and produce
fertile offspring" just opens up a different set of ambiguities. It's
not as clear and concise a definition as it seems on the surface.

If you accept man's intervention to define what breeding and fertile
offspring means (which I assume you do - if you don't I can also make
the other side of the argument) you are left with two choices:

1. To decide how much and what kind of intervention is "allowed"

or

2. Accept that the definition of species will keep changing as man's
technology develops. This, IMO, will lead to some VERY strange
conclusions in the future.

Willi

"Wolfgang" wrote in message
...
Plants......you forgot about plants. How about an apple trunk grafted
onto
pear rootstock and later augmented with plum and cherry branches? (It's
doable.....they're all Rosaceae and graft relatively easily.)


Interesting. "Relatively easily." "Doable." So you've grafted plum and
cherry branches sucessfully onto an apple trunk, have you? What were the
varieties pray tell?

Dave

"David Snedeker" wrote in message
...

"Wolfgang" wrote in message
...
Plants......you forgot about plants. How about an apple trunk grafted
onto
pear rootstock and later augmented with plum and cherry branches? (It's
doable.....they're all Rosaceae and graft relatively easily.)


Interesting.

Isn't it?

"Relatively easily."

Yep.

"Doable."

Yep.

So you've grafted plum and
cherry branches sucessfully onto an apple trunk, have you?

Nope.

What were the
varieties pray tell?

My uncle and his cousin both grafted various members of the Rosaceae onto
one another. I have no idea what varieties they used. As they were both of
peasant stock with something less than a high school education, neither
spoke any English on arriving in the U.S., and both spent the better part of
their lives doing manual labor during the daylight hours and drinking
themselves into oblivion in the evenings, I suspect neither of them ever
bothered to learn what varieties they were either. What's more, they
probably didn't know a great deal about current events and I'm certain they
couldn't pass themselves off as authorities on suitable substrates for oil
based paints. Uncle Art DID have a velvet collar on a coat he owned back in
the 50s, though.

Wolfgang