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Don Cates
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 Posted: Sat Jun 07, 2008 3:34 am Post subject: OT: Peregrine falcons again |
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The three chicks I mentioned before died this morning in a very heavy
rainfall. There is hope the parents might try again since there is still
time.
--
Don Cates ("he's a cunning rascal" - PN) |
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Dan Luke
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| Posted: Sat Jun 07, 2008 4:20 am Post subject: Re: Peregrine falcons again |
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"Don Cates" wrote:
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The three chicks I mentioned before died this morning in a very heavy
rainfall. There is hope the parents might try again since there is still
time.
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Too bad.
Selection pressure is tough.
--
Dan
"Don't make me nervous when I'm holdin' a baseball bat."
-Big Joe Turner |
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J. J. Lodder
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| Posted: Sat Jun 07, 2008 11:01 am Post subject: Re: Peregrine falcons again |
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Dan Luke <t182t@dingdongsouth.net> wrote:
| Quote: |
"Don Cates" wrote:
The three chicks I mentioned before died this morning in a very heavy
rainfall. There is hope the parents might try again since there is still
time.
Too bad.
Selection pressure is tough.
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Standard mistake again.
What has selection pressure got to do with it?
Those three might have been the fittest falcons ever,
with just some unusually bad luck,
Jan |
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chris thompson
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| Posted: Mon Jun 09, 2008 1:41 am Post subject: Re: Peregrine falcons again |
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On Jun 8, 9:03 pm, Vernon Balbert <vbalb...@gmail.nospam.com> wrote:
| Quote: |
On 6/8/2008 2:49 PM, chris thompson went clickity clack on the keyboard
and produced this interesting bit of text:
On Jun 7, 11:47 am, Vernon Balbert <vbalb...@gmail.nospam.com> wrote:
On 6/7/2008 12:32 AM, J. J. Lodder went clickity clack on the keyboard
and produced this interesting bit of text:
Dan Luke <t1...@dingdongsouth.net> wrote:
"Don Cates" wrote:
The three chicks I mentioned before died this morning in a very heavy
rainfall. There is hope the parents might try again since there is still
time.
Too bad.
Selection pressure is tough.
Standard mistake again.
What has selection pressure got to do with it?
Those three might have been the fittest falcons ever,
with just some unusually bad luck,
Obviously, they were not fit enough to survive the torrential downpour.
This is what natural selection does. It has no logic. Of course
babies aren't going to be fit to survive things that the adults can and
there was no way to predict that the nest was built in a bad spot. In
fact, it's probably a good spot. The same thing would have happened in
a lot of good spots, too. But natural selection does not have any
direction or will. This is an example of natural selection. Perhaps
falcons will evolve a weatherproof nesting procedure because of this.
Not likely, but who can say?
--
Real programmers never work 9 to 5. If any real programmers are around
at 9 am, it's because they were up all night.
Fitness is measured by reproductive success. It's a mistake to say
"Fitter parents might have been able to build a better nest" or "they
weren't fit enough to survive". Fitness isn't measured by survival.
and it's trivial to say fitter parents build nests in which their
young survive.
I was referring to the chicks who weren't fit enough to survive. The
parents were obviously fit in that they produced a clutch of eggs that
hatched. It is entirely probable that they will lay another clutch.
Maybe not this year, but unless one dies between now and then, it's
pretty likely they'll do it next year.
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In a biological sense, 'weren't fit enough to survive' doesn't have
meaning. If they die without reproducing their fitness is zero.
It doesn't matter that the parents produced a clutch of eggs. The
chicks died without breeding, so the parents' fitnesses are reduced.
| Quote: |
What might be more appropriate here is to ask whether this was density-
dependent or density-independent mortality. In general, natural
selection is thought to act more strongly in a density-dependent
manner. That is, when there's competition with conspecifics for
resources, natural selection begins to operate. Density-independent
mortality (and this seems to be a classic case) doesn't really give
organisms a chance to prove their stuff. It really is a matter of
good or bad luck, being in the right or wrong place at the right time,
that sort of thing.
Without knowing the specifics of what happened to the chicks, it's still
natural selection. If the situation were such that the chicks could
have done something to increase their survival; i.e. the ability to
swim, or at least keep a head above water without getting washed away,
then those chicks would have been more fit. Environment is a strong
part of natural selection and that's exactly what we're talking about
here. Fitness isn't always a case of whether or not the organism is
out-competed by other organisms.
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Well, no, it is not necessarily selection. It is selection if some
genetic factor was responsible for the deaths. If it was a case of a
freak torrential downpour drowning them, it probably isn't selection.
And once again, the survival of the chicks does not increase their
fitness. Don't mistake fitness for 'physical condition'. Fitness [in
an evolutionary sense] is reproductive success, nothing more or less.
Chris
| Quote: |
--
It is better to be a mouse in a cat's mouth than a man in a lawyer's
hands. - Spanish Proverb |
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Bob Casanova
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| Posted: Tue Jun 10, 2008 6:56 am Post subject: Re: OT: Peregrine falcons again |
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On Sun, 8 Jun 2008 14:54:26 -0700 (PDT), the following
appeared in talk.origins, posted by chris thompson
<chris.linthompson@gmail.com>:
| Quote: |
On Jun 8, 8:37 am, Nashton <n...@na.ca> wrote:
Don Cates wrote:
The three chicks I mentioned before died this morning in a very heavy
rainfall. There is hope the parents might try again since there is still
time.
15x10^6 children/year die from hunger, *hunger*, for crying out loud.
Another 10x10^6 die from preventable disease (pneumonia, asphyxia at
birth, diarrhea) and we should care about a couple of birds that didn't
get their eggs to hatch? A bird that isn't even on the endangered list,
IIRC.
Used up your caring ability, eh? Sad, that. Most of us can be
concerned about them all.
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"Nashie" and "empathy" are orthogonal.
--
Bob C.
"Evidence confirming an observation is
evidence that the observation is wrong."
- McNameless |
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