| Topic: |
Religions > Atheism |
| User: |
"Speed" |
| Date: |
03 Apr 2007 08:01:33 PM |
| Object: |
Evolution question |
I accept evolution, but I often find myself wondering about it. I live
out in the country and see a lot of wild animals. The other day I
walked right past a jackrabbit and didn't even see him until he began
to move, and this his white cottontail instantly gave him away.
It got me wondering: how did the jackrabbit evolve with body fur that
perfectly matches the dry brush, but he has this white cottontail that
sticks out like a sore thumb? It seems like all the white-tailed
rabbits should have been killed off by predators and rabbits with
brown tails would have been the only survivors.
.
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| User: "Michael Gray" |
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| Title: Re: Evolution question |
04 Apr 2007 01:02:48 AM |
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On Tue, 03 Apr 2007 18:01:33 -0700, Speed <nope@nope.com> wrote:
- Refer: <dut5139k4fquajo99mf3bdg27mcps207f1@4ax.com>
I accept evolution, but I often find myself wondering about it. I live
out in the country and see a lot of wild animals. The other day I
walked right past a jackrabbit and didn't even see him until he began
to move, and this his white cottontail instantly gave him away.
It got me wondering: how did the jackrabbit evolve with body fur that
perfectly matches the dry brush, but he has this white cottontail that
sticks out like a sore thumb? It seems like all the white-tailed
rabbits should have been killed off by predators and rabbits with
brown tails would have been the only survivors.
It serves as flag to family members, much as a dog wags it's tail as a
slient signal to the others in the pack.
--
.
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| User: "Dubh Ghall" |
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| Title: Re: Evolution question |
04 Apr 2007 01:09:27 PM |
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On Tue, 03 Apr 2007 18:01:33 -0700, Speed <nope@nope.com> wrote:
I accept evolution, but I often find myself wondering about it. I live
out in the country and see a lot of wild animals. The other day I
walked right past a jackrabbit and didn't even see him until he began
to move, and this his white cottontail instantly gave him away.
It got me wondering: how did the jackrabbit evolve with body fur that
perfectly matches the dry brush, but he has this white cottontail that
sticks out like a sore thumb? It seems like all the white-tailed
rabbits should have been killed off by predators and rabbits with
brown tails would have been the only survivors.
But you didn't see/notice his white tail; did you?
Most mammalian predators, are colour blind, so the actual colour of
the scutty's fur is not very important, from that pov, although the
shade and pattern can be.
What matters is the scutty's ability to remain still, and/or run.
The white flag, and it's habit of thumping on the ground when danger
threatens, act as an alert to other rabbits.
If you have ever hunted rabbits, you would have noticed that a rabbit
can move quite quickly across a field, and attract little attention
from the others feeding there.
But let it run with it's little white scut showing, and in nothing
flat, there aint a rabbit to be seen.
--
The spelling Like any opinion stated here
purely my own
#162 BAAWA Knight.
.
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| User: "Matt Silberstein" |
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| Title: Re: Evolution question |
04 Apr 2007 03:37:48 PM |
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On Wed, 04 Apr 2007 18:09:27 GMT, in alt.atheism , Dubh Ghall
<puck@pooks.hill.fey> in <gek863t5keb8g730cvtu60qpgrje4foeut@4ax.com>
wrote:
On Tue, 03 Apr 2007 18:01:33 -0700, Speed <nope@nope.com> wrote:
I accept evolution, but I often find myself wondering about it. I live
out in the country and see a lot of wild animals. The other day I
walked right past a jackrabbit and didn't even see him until he began
to move, and this his white cottontail instantly gave him away.
It got me wondering: how did the jackrabbit evolve with body fur that
perfectly matches the dry brush, but he has this white cottontail that
sticks out like a sore thumb? It seems like all the white-tailed
rabbits should have been killed off by predators and rabbits with
brown tails would have been the only survivors.
But you didn't see/notice his white tail; did you?
Most mammalian predators, are colour blind, so the actual colour of
the scutty's fur is not very important, from that pov, although the
shade and pattern can be.
Do you really know that the difference in color there is not
noticeable or are you guessing?
What matters is the scutty's ability to remain still, and/or run.
By your logic we should find some bright colors animals in the same
area.
The white flag, and it's habit of thumping on the ground when danger
threatens, act as an alert to other rabbits.
How does the color do that? Are you saying that the rabbits can see
the white while the predators can't?
If you have ever hunted rabbits, you would have noticed that a rabbit
can move quite quickly across a field, and attract little attention
from the others feeding there.
But let it run with it's little white scut showing, and in nothing
flat, there aint a rabbit to be seen.
--
Matt Silberstein
Do something today about the Darfur Genocide
http://www.beawitness.org
http://www.darfurgenocide.org
http://www.savedarfur.org
"Darfur: A Genocide We can Stop"
.
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| User: "Ben Kaufman" |
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| Title: Re: Evolution question |
03 Apr 2007 08:17:24 PM |
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On Tue, 03 Apr 2007 18:01:33 -0700, Speed <nope@nope.com> wrote:
I accept evolution, but I often find myself wondering about it. I live
out in the country and see a lot of wild animals. The other day I
walked right past a jackrabbit and didn't even see him until he began
to move, and this his white cottontail instantly gave him away.
It got me wondering: how did the jackrabbit evolve with body fur that
perfectly matches the dry brush, but he has this white cottontail that
sticks out like a sore thumb? It seems like all the white-tailed
rabbits should have been killed off by predators and rabbits with
brown tails would have been the only survivors.
Generally, when an animal is trying to avoid detection it stays motionless, and
thus the tail would be hidden. If the rabbit moves it's either because it
doesn't feel a threat or it believes that the predator has already detected him
and it's time to flee. Perhaps the sudden flash of a white tail has the effect
of throwing off the predator for an instant. Perhaps during the chase the
predator zones in on the tail and does not read other body motion of the rabbit
so a dart or U-turn comes as a greater surprise. Maybe the tail whiteness is
useful for having the offspring follow it, and/or to cause a distraction to a
predator that would otherwise zero in on one of the babies.
Ben
.
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| User: "Elroy Willis" |
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| Title: Re: Evolution question |
04 Apr 2007 08:36:22 AM |
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Ben Kaufman wrote in alt.atheism
Speed <nope@nope.com> wrote:
I accept evolution, but I often find myself wondering about it. I live
out in the country and see a lot of wild animals. The other day I
walked right past a jackrabbit and didn't even see him until he began
to move, and this his white cottontail instantly gave him away.
It got me wondering: how did the jackrabbit evolve with body fur that
perfectly matches the dry brush, but he has this white cottontail that
sticks out like a sore thumb? It seems like all the white-tailed
rabbits should have been killed off by predators and rabbits with
brown tails would have been the only survivors.
Generally, when an animal is trying to avoid detection it stays motionless, and
thus the tail would be hidden. If the rabbit moves it's either because it
doesn't feel a threat or it believes that the predator has already detected him
and it's time to flee. Perhaps the sudden flash of a white tail has the effect
of throwing off the predator for an instant. Perhaps during the chase the
predator zones in on the tail and does not read other body motion of the rabbit
so a dart or U-turn comes as a greater surprise. Maybe the tail whiteness is
useful for having the offspring follow it, and/or to cause a distraction to a
predator that would otherwise zero in on one of the babies.
It's the same for the white-tailed deer around here. They generally
have their tails down when grazing, but once they feel a threat the
white tail goes up like a flag. It alerts other deer to the danger
and helps the herd survive. I don't think rabbits flash their white
tails when they're calmly eating or aren't in danger, do they?
--
Elroy Willis
www.elroysemporium.com
.
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| User: "Ben Kaufman" |
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| Title: Re: Evolution question |
04 Apr 2007 10:25:00 AM |
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On Wed, 04 Apr 2007 13:36:22 GMT, Elroy Willis <elroywillis@swbell.net> wrote:
Ben Kaufman wrote in alt.atheism
Speed <nope@nope.com> wrote:
I accept evolution, but I often find myself wondering about it. I live
out in the country and see a lot of wild animals. The other day I
walked right past a jackrabbit and didn't even see him until he began
to move, and this his white cottontail instantly gave him away.
It got me wondering: how did the jackrabbit evolve with body fur that
perfectly matches the dry brush, but he has this white cottontail that
sticks out like a sore thumb? It seems like all the white-tailed
rabbits should have been killed off by predators and rabbits with
brown tails would have been the only survivors.
Generally, when an animal is trying to avoid detection it stays motionless, and
thus the tail would be hidden. If the rabbit moves it's either because it
doesn't feel a threat or it believes that the predator has already detected him
and it's time to flee. Perhaps the sudden flash of a white tail has the effect
of throwing off the predator for an instant. Perhaps during the chase the
predator zones in on the tail and does not read other body motion of the rabbit
so a dart or U-turn comes as a greater surprise. Maybe the tail whiteness is
useful for having the offspring follow it, and/or to cause a distraction to a
predator that would otherwise zero in on one of the babies.
It's the same for the white-tailed deer around here. They generally
have their tails down when grazing, but once they feel a threat the
white tail goes up like a flag. It alerts other deer to the danger
and helps the herd survive. I don't think rabbits flash their white
tails when they're calmly eating or aren't in danger, do they?
From what i've seen in my backyard they sit on their rumps while munching on
vegetation..
Ben
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| User: "Matt Silberstein" |
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| Title: Re: Evolution question |
04 Apr 2007 07:24:43 AM |
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On Tue, 03 Apr 2007 18:01:33 -0700, in alt.atheism , Speed
<nope@nope.com> in <dut5139k4fquajo99mf3bdg27mcps207f1@4ax.com> wrote:
I accept evolution, but I often find myself wondering about it. I live
out in the country and see a lot of wild animals. The other day I
walked right past a jackrabbit and didn't even see him until he began
to move, and this his white cottontail instantly gave him away.
It got me wondering: how did the jackrabbit evolve with body fur that
perfectly matches the dry brush, but he has this white cottontail that
sticks out like a sore thumb? It seems like all the white-tailed
rabbits should have been killed off by predators and rabbits with
brown tails would have been the only survivors.
You wondered because you could not think of a reason, three people
gave you three different reasons, all of this shows a problem with all
of your thinking. Let me try to lay out those problems. First, yours:
just because you can't think of a selective reason for something does
not mean no such reason exists. Biota are not limited to solutions
that fit your thinking. Second, not all features have a selective
cause: neutral drift is a powerful force and quite possibly the cause
of most evolutionary change. Now for those who offered (possible)
selective advantages: stop reading so much Dawkins. You all offered
what are called just-so stories, you supplied possible selection
values without any supporting evidence. Just because something seems
reasonable (or unreasonable) does not make it so (or not so). Balance
reading Dawkins with reading some Gould.
--
Matt Silberstein
Do something today about the Darfur Genocide
http://www.beawitness.org
http://www.darfurgenocide.org
http://www.savedarfur.org
"Darfur: A Genocide We can Stop"
.
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| User: "Elroy Willis" |
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| Title: Re: Evolution question |
04 Apr 2007 09:17:49 AM |
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Matt Silberstein wrote in alt.atheism
in alt.atheism , Speed wrote:
I accept evolution, but I often find myself wondering about it. I live
out in the country and see a lot of wild animals. The other day I
walked right past a jackrabbit and didn't even see him until he began
to move, and this his white cottontail instantly gave him away.
It got me wondering: how did the jackrabbit evolve with body fur that
perfectly matches the dry brush, but he has this white cottontail that
sticks out like a sore thumb? It seems like all the white-tailed
rabbits should have been killed off by predators and rabbits with
brown tails would have been the only survivors.
You wondered because you could not think of a reason, three people
gave you three different reasons, all of this shows a problem with all
of your thinking. Let me try to lay out those problems. First, yours:
just because you can't think of a selective reason for something does
not mean no such reason exists. Biota are not limited to solutions
that fit your thinking. Second, not all features have a selective
cause: neutral drift is a powerful force and quite possibly the cause
of most evolutionary change. Now for those who offered (possible)
selective advantages: stop reading so much Dawkins. You all offered
what are called just-so stories, you supplied possible selection
values without any supporting evidence. Just because something seems
reasonable (or unreasonable) does not make it so (or not so). Balance
reading Dawkins with reading some Gould.
You are such an *****! The guy asks an honest question, and
you slam him for it, as well as the people who responded to him.
--
Elroy Willis
www.elroysemporium.com
.
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| User: "Christopher A.Lee" |
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| Title: Re: Evolution question |
04 Apr 2007 09:36:47 AM |
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On Wed, 04 Apr 2007 09:17:49 -0500, Elroy Willis
<elroywillis@swbell.net> wrote:
Matt Silberstein wrote in alt.atheism
in alt.atheism , Speed wrote:
I accept evolution, but I often find myself wondering about it. I live
out in the country and see a lot of wild animals. The other day I
walked right past a jackrabbit and didn't even see him until he began
to move, and this his white cottontail instantly gave him away.
It got me wondering: how did the jackrabbit evolve with body fur that
perfectly matches the dry brush, but he has this white cottontail that
sticks out like a sore thumb? It seems like all the white-tailed
rabbits should have been killed off by predators and rabbits with
brown tails would have been the only survivors.
You wondered because you could not think of a reason, three people
gave you three different reasons, all of this shows a problem with all
of your thinking. Let me try to lay out those problems. First, yours:
just because you can't think of a selective reason for something does
not mean no such reason exists. Biota are not limited to solutions
that fit your thinking. Second, not all features have a selective
cause: neutral drift is a powerful force and quite possibly the cause
of most evolutionary change. Now for those who offered (possible)
selective advantages: stop reading so much Dawkins. You all offered
what are called just-so stories, you supplied possible selection
values without any supporting evidence. Just because something seems
reasonable (or unreasonable) does not make it so (or not so). Balance
reading Dawkins with reading some Gould.
You are such an *****! The guy asks an honest question, and
you slam him for it, as well as the people who responded to him.
It's Silberstein. I killfiled him long ago for that sort of thing.
.
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| User: "Elroy Willis" |
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| Title: Re: Evolution question |
04 Apr 2007 10:02:01 AM |
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Christopher A.Lee <calee@optonline.net> wrote in alt.atheism
Elroy Willis <elroywillis@swbell.net> wrote:
Matt Silberstein wrote in alt.atheism
in alt.atheism , Speed wrote:
I accept evolution, but I often find myself wondering about it. I live
out in the country and see a lot of wild animals. The other day I
walked right past a jackrabbit and didn't even see him until he began
to move, and this his white cottontail instantly gave him away.
It got me wondering: how did the jackrabbit evolve with body fur that
perfectly matches the dry brush, but he has this white cottontail that
sticks out like a sore thumb? It seems like all the white-tailed
rabbits should have been killed off by predators and rabbits with
brown tails would have been the only survivors.
You wondered because you could not think of a reason, three people
gave you three different reasons, all of this shows a problem with all
of your thinking.
Look how he pretends to know everything, or at least more than anyone
else around here...
Let me try to lay out those problems. First, yours:
just because you can't think of a selective reason for something does
not mean no such reason exists. Biota are not limited to solutions
that fit your thinking. Second, not all features have a selective
cause: neutral drift is a powerful force and quite possibly the cause
of most evolutionary change. Now for those who offered (possible)
selective advantages: stop reading so much Dawkins. You all offered
what are called just-so stories, you supplied possible selection
values without any supporting evidence. Just because something seems
reasonable (or unreasonable) does not make it so (or not so). Balance
reading Dawkins with reading some Gould.
You are such an *****! The guy asks an honest question, and
you slam him for it, as well as the people who responded to him.
It's Silberstein. I killfiled him long ago for that sort of thing.
I suspect quite a few others have done the same. He ridicules people
for trying to learn by asking honest questions. I'm pretty sure he
doesn't subscribe to the idea that "no question is a stupid question,"
in the process and interest of learning.
He's actually been teetering on the edge of my killfile for a while
now, and I think the above might've put him over the edge.
--
Elroy Willis
www.elroysemporium.com
.
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| User: "Matt Silberstein" |
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| Title: Re: Evolution question |
04 Apr 2007 10:46:01 AM |
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On Wed, 04 Apr 2007 09:17:49 -0500, in alt.atheism , Elroy Willis
<elroywillis@swbell.net> in
<2kc713pcbhlfiofl923i00jv78l5h78ebd@4ax.com> wrote:
Matt Silberstein wrote in alt.atheism
in alt.atheism , Speed wrote:
I accept evolution, but I often find myself wondering about it. I live
out in the country and see a lot of wild animals. The other day I
walked right past a jackrabbit and didn't even see him until he began
to move, and this his white cottontail instantly gave him away.
It got me wondering: how did the jackrabbit evolve with body fur that
perfectly matches the dry brush, but he has this white cottontail that
sticks out like a sore thumb? It seems like all the white-tailed
rabbits should have been killed off by predators and rabbits with
brown tails would have been the only survivors.
You wondered because you could not think of a reason, three people
gave you three different reasons, all of this shows a problem with all
of your thinking. Let me try to lay out those problems. First, yours:
just because you can't think of a selective reason for something does
not mean no such reason exists. Biota are not limited to solutions
that fit your thinking. Second, not all features have a selective
cause: neutral drift is a powerful force and quite possibly the cause
of most evolutionary change. Now for those who offered (possible)
selective advantages: stop reading so much Dawkins. You all offered
what are called just-so stories, you supplied possible selection
values without any supporting evidence. Just because something seems
reasonable (or unreasonable) does not make it so (or not so). Balance
reading Dawkins with reading some Gould.
You are such an *****! The guy asks an honest question, and
you slam him for it, as well as the people who responded to him.
I did not slam him, I corrected an incorrect assumption in the
question. Bad science is bad science. Unfortunately lots of people
here have taken to Dawkins "worship" for this theology rather than his
science. Here is a clue: there is no real connection between the two.
He could be right about one, the other, both, or even neither. As it
happens he is wrong about his ultra-Darwinism. And the others who
responded, honest or not, were wrong to offer answers that have no
evidence to support them. I ask you why you think that evidence-less
answers, even (or especially) in the name of science, are a good
thing?
--
Matt Silberstein
Do something today about the Darfur Genocide
http://www.beawitness.org
http://www.darfurgenocide.org
http://www.savedarfur.org
"Darfur: A Genocide We can Stop"
.
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| User: "Ben Kaufman" |
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| Title: Re: Evolution question |
04 Apr 2007 10:35:11 AM |
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On Wed, 04 Apr 2007 12:24:43 GMT, Matt Silberstein
<RemoveThisPrefixmatts2nospam@ix.netcom.com> wrote:
On Tue, 03 Apr 2007 18:01:33 -0700, in alt.atheism , Speed
<nope@nope.com> in <dut5139k4fquajo99mf3bdg27mcps207f1@4ax.com> wrote:
I accept evolution, but I often find myself wondering about it. I live
out in the country and see a lot of wild animals. The other day I
walked right past a jackrabbit and didn't even see him until he began
to move, and this his white cottontail instantly gave him away.
It got me wondering: how did the jackrabbit evolve with body fur that
perfectly matches the dry brush, but he has this white cottontail that
sticks out like a sore thumb? It seems like all the white-tailed
rabbits should have been killed off by predators and rabbits with
brown tails would have been the only survivors.
You wondered because you could not think of a reason, three people
gave you three different reasons, all of this shows a problem with all
of your thinking. Let me try to lay out those problems. First, yours:
just because you can't think of a selective reason for something does
not mean no such reason exists. Biota are not limited to solutions
that fit your thinking. Second, not all features have a selective
cause: neutral drift is a powerful force and quite possibly the cause
of most evolutionary change. Now for those who offered (possible)
selective advantages: stop reading so much Dawkins. You all offered
what are called just-so stories, you supplied possible selection
values without any supporting evidence. Just because something seems
reasonable (or unreasonable) does not make it so (or not so). Balance
reading Dawkins with reading some Gould.
Matt,
I am very bewildered by the third prong of your response. On the one hand you
state that we were offering "possibilities" but on the other you attack it as if
we were insisting that the tail had to be of some evolutionary benefit.
Ben
.
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| User: "Matt Silberstein" |
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| Title: Re: Evolution question |
04 Apr 2007 11:27:10 AM |
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On Wed, 04 Apr 2007 11:35:11 -0400, in alt.atheism , Ben Kaufman
<spaXm-mXe-anXd-paXy-5000-dollars@pobox.com> in
<82h7131opr0ov218b8rd9tcgg45fkiro3u@4ax.com> wrote:
On Wed, 04 Apr 2007 12:24:43 GMT, Matt Silberstein
<RemoveThisPrefixmatts2nospam@ix.netcom.com> wrote:
On Tue, 03 Apr 2007 18:01:33 -0700, in alt.atheism , Speed
<nope@nope.com> in <dut5139k4fquajo99mf3bdg27mcps207f1@4ax.com> wrote:
I accept evolution, but I often find myself wondering about it. I live
out in the country and see a lot of wild animals. The other day I
walked right past a jackrabbit and didn't even see him until he began
to move, and this his white cottontail instantly gave him away.
It got me wondering: how did the jackrabbit evolve with body fur that
perfectly matches the dry brush, but he has this white cottontail that
sticks out like a sore thumb? It seems like all the white-tailed
rabbits should have been killed off by predators and rabbits with
brown tails would have been the only survivors.
You wondered because you could not think of a reason, three people
gave you three different reasons, all of this shows a problem with all
of your thinking. Let me try to lay out those problems. First, yours:
just because you can't think of a selective reason for something does
not mean no such reason exists. Biota are not limited to solutions
that fit your thinking. Second, not all features have a selective
cause: neutral drift is a powerful force and quite possibly the cause
of most evolutionary change. Now for those who offered (possible)
selective advantages: stop reading so much Dawkins. You all offered
what are called just-so stories, you supplied possible selection
values without any supporting evidence. Just because something seems
reasonable (or unreasonable) does not make it so (or not so). Balance
reading Dawkins with reading some Gould.
Matt,
I am very bewildered by the third prong of your response. On the one hand you
state that we were offering "possibilities" but on the other you attack it as if
we were insisting that the tail had to be of some evolutionary benefit.
You all went in with the assumption that the feature has a selective
value and tried to guess, with more or less clear statements that it
was just a guess, on the value. My point is that "trait X has a
selective value" is not the default, the default is that it is
neutral, selective value is something to be demonstrated with
evidence. I can imagine many reasons why a white tail could be a
positive or negative selective trait, but until I have evidence for it
I just don't know. As I said, I think there is too much of learning
evolution from Dawkins and so too much emphasis on selection as *the*
evolutionary force. It exists and is important, but, *by the
evidence*, most evolutionary change is neutral, not selective.
There is also a whole other set of possibilities and for that I will
shift to a different mammal: cats. Someone could easily ask why cats
often have white feet and black bodies and wonder about the selective
value of that. And we could speculate on various things. And we would,
in that case, be wrong. Cats have white feet because of how cats
develop. The color cells start at the spine and in utero they migrate
down the body. So the last places they will reach are the feet or
stomach. For *developmental*, not *selective* reasons we are quite
unlikely to see a cat with black feet and a white body. There may well
be a similar developmental constraint on rabbits and deer I have no
idea. In this case I am not even speculating.
--
Matt Silberstein
Do something today about the Darfur Genocide
http://www.beawitness.org
http://www.darfurgenocide.org
http://www.savedarfur.org
"Darfur: A Genocide We can Stop"
.
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| User: "Ben Kaufman" |
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| Title: Re: Evolution question |
04 Apr 2007 04:01:03 PM |
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On Wed, 04 Apr 2007 16:27:10 GMT, Matt Silberstein
<RemoveThisPrefixmatts2nospam@ix.netcom.com> wrote:
On Wed, 04 Apr 2007 11:35:11 -0400, in alt.atheism , Ben Kaufman
<spaXm-mXe-anXd-paXy-5000-dollars@pobox.com> in
<82h7131opr0ov218b8rd9tcgg45fkiro3u@4ax.com> wrote:
On Wed, 04 Apr 2007 12:24:43 GMT, Matt Silberstein
<RemoveThisPrefixmatts2nospam@ix.netcom.com> wrote:
On Tue, 03 Apr 2007 18:01:33 -0700, in alt.atheism , Speed
<nope@nope.com> in <dut5139k4fquajo99mf3bdg27mcps207f1@4ax.com> wrote:
I accept evolution, but I often find myself wondering about it. I live
out in the country and see a lot of wild animals. The other day I
walked right past a jackrabbit and didn't even see him until he began
to move, and this his white cottontail instantly gave him away.
It got me wondering: how did the jackrabbit evolve with body fur that
perfectly matches the dry brush, but he has this white cottontail that
sticks out like a sore thumb? It seems like all the white-tailed
rabbits should have been killed off by predators and rabbits with
brown tails would have been the only survivors.
You wondered because you could not think of a reason, three people
gave you three different reasons, all of this shows a problem with all
of your thinking. Let me try to lay out those problems. First, yours:
just because you can't think of a selective reason for something does
not mean no such reason exists. Biota are not limited to solutions
that fit your thinking. Second, not all features have a selective
cause: neutral drift is a powerful force and quite possibly the cause
of most evolutionary change. Now for those who offered (possible)
selective advantages: stop reading so much Dawkins. You all offered
what are called just-so stories, you supplied possible selection
values without any supporting evidence. Just because something seems
reasonable (or unreasonable) does not make it so (or not so). Balance
reading Dawkins with reading some Gould.
Matt,
I am very bewildered by the third prong of your response. On the one hand you
state that we were offering "possibilities" but on the other you attack it as if
we were insisting that the tail had to be of some evolutionary benefit.
You all went in with the assumption that the feature has a selective
value and tried to guess, with more or less clear statements that it
was just a guess, on the value.
You are taking it out of context. We were just trying to show the OP the
possibilities on the other side of the coin, regardless of whether it is
actually negative, neutral or positive.
My point is that "trait X has a
selective value" is not the default, the default is that it is
neutral, selective value is something to be demonstrated with
evidence.
I can imagine many reasons why a white tail could be a
positive or negative selective trait, but until I have evidence for it
I just don't know.
As I said, I think there is too much of learning
evolution from Dawkins and so too much emphasis on selection as *the*
evolutionary force. It exists and is important, but, *by the
evidence*, most evolutionary change is neutral, not selective.
And *by the evidence* (whatever that is, and I hope you will cite it) that these
traits are less dramatic than something that would have the potential for making
a significant change in the predator/prey relationship?
There is also a whole other set of possibilities and for that I will
shift to a different mammal: cats. Someone could easily ask why cats
often have white feet and black bodies and wonder about the selective
value of that. And we could speculate on various things. And we would,
in that case, be wrong. Cats have white feet because of how cats
develop. The color cells start at the spine and in utero they migrate
down the body. So the last places they will reach are the feet or
stomach. For *developmental*, not *selective* reasons we are quite
unlikely to see a cat with black feet and a white body. There may well
be a similar developmental constraint on rabbits and deer I have no
idea. In this case I am not even speculating.
Whoa, hold on there sailor! You don't recognize that evolutionary significant
traits are caused by the developmental process? Me thinks you need to read up
on embryology.
Ben
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| User: "TheLetterK" |
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| Title: Re: Evolution question |
04 Apr 2007 10:24:24 AM |
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Speed wrote:
I accept evolution, but I often find myself wondering about it. I live
out in the country and see a lot of wild animals. The other day I
walked right past a jackrabbit and didn't even see him until he began
to move, and this his white cottontail instantly gave him away.
It got me wondering: how did the jackrabbit evolve with body fur that
perfectly matches the dry brush, but he has this white cottontail that
sticks out like a sore thumb?
Perhaps there is no allele for brown tails in that breeding population.
It seems like all the white-tailed
rabbits should have been killed off by predators and rabbits with
brown tails would have been the only survivors.
All of them? Probably not. I don't know enough about jackrabbits to cite
a specific reason, but if there is a brown tail allele in that
population, then there must be some advantage to having a white tail
(though this advantage may have been in the past). Then there's also the
possibility that you ran across a jackrabbit with an uncommon trait.
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| User: "John Popelish" |
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| Title: Re: Evolution question |
03 Apr 2007 07:08:01 PM |
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Speed wrote:
I accept evolution, but I often find myself wondering about it. I live
out in the country and see a lot of wild animals. The other day I
walked right past a jackrabbit and didn't even see him until he began
to move, and this his white cottontail instantly gave him away.
It got me wondering: how did the jackrabbit evolve with body fur that
perfectly matches the dry brush, but he has this white cottontail that
sticks out like a sore thumb? It seems like all the white-tailed
rabbits should have been killed off by predators and rabbits with
brown tails would have been the only survivors.
Perhaps members of the opposite sex find it to be a powerful
turn on. Works for peacocks. You have to not only evade
predators, you have to get laid.
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