Re: [ECOLOG-L] Discussion Panel Topic Suggestions

[Mitch Cruzan]

Jeff - You ask:

How can you state definitively that species 3 billion years ago were just as 
well adapted to their environment as those that exist today?
- It is a logical expectation.  Selection was no less strong 3 billion 
years ago than it is today, so organisms of the day were as "adapted" to 
their environments as anything today.  At that time the basic molecular 
machinery of cell metabolism was already established.  We know this 
because these metabolic pathways are largely conserved across 
Eukaryotes.  The difference is that everything at that time were 
probably unicellular.
    The point is that the environment has changed.  Would those 3 
billion year old microbes succeed today?  Probably not.  By the same 
logic, organisms today would not do well in that Precambrian environment 
-  the physical, chemical, and biological conditions were so different 
that almost all modern forms would quickly expire.  No food in 
terrestrial environments, nothing larger to eat than microbes in the 
water.  The chemical composition of the oceans and atmosphere were very 
different than today.  The environment at that time lacked much of the 
biological complexity that exists today.  So yes, they were very well 
adapted to their environment - it was a very different kind of place.
   There may be some confusion between "better adapted" and 
innovation.  The evolutionary innovations allowed organisms to engage in 
novel methods of resource acquisition - they are different, but not better.

- Organisms are constrained from being adapted to their current 
environment.  It is not that they are just not quite perfect, but that 
they may be pretty far from a theoretical optimum.  Take the Lenske 
experimental evolution example - those microbes evolved because they 
were challenged by a novel resource that they could not metabolize very 
well.  As mutations appeared that improved efficiency the population 
size increased.  The really interesting thing is that they used multiple 
populations, and they evolved on different trajectories.  In other 
words, different populations solved the problems in different ways, and 
some ultimately achieved higher population densities - reflecting higher 
metabolic efficiency - than others.  If we imagine these populations 
moving across an adaptive landscape then this is analogous to traveling 
up different adaptive peaks.  Once they are near the top of a peak they 
can get stuck unless the environment changes, which creates a new 
landscape.  The point is that there may be much higher peaks on this 
landscape that none of the population were able to climb.

I hope those examples help.

Mitch Cruzan

On 12/7/2012 1:26 AM, Jeff Houlahan wrote:
Hi all, my difficulty with this is that what I see as a difference of opinion 
continues to get characterised as a misunderstanding of evolution.  Mitch, how 
can you state definitively that species 3 billion years ago were just as well 
adapted to their environment as those that exist today? It seems to me that's 
an empirical question.   It's possible they were but why MUST it be so.  And if 
I can provide an empirical example (Lenski's experiments) where later 
generations of an E.coli population were better adapted for their environment 
than an earlier one (by directly testing the competitive ability of the two 
strains) then why is it not possible that organisms today, on average, are 
better adapted for their environment than past organisms.  I want to emphasize 
that I am not saying current organisms ARE better adapted, only that it's a 
legitimate question to ask.  The answer will be in the data.

' In evolution different species can't be compared as better or worse - they 
just succeed or they are replaced by
others.'

So, we can use the term successful but not better?  OK.  So, is there any 
evidence that current organisms have more success dealing with their 
environment than ones from 3 billion years ago?

'The upshot is that populations and species are never adapted to their
environments.'

It's not clear to me what you mean here, Mitch.  That they aren't perfectly 
adapted to their environments?  I don't think anybody has suggested they are.  
'That environments are always changing so 'adapted' is a moving target?  That 
is almost certainly true but it doesn't mean, necessarily, that one step 
forward and one step back.  It could be that there is a noisy and variable walk 
towards organisms that are more successful at dealing with their environments.  
But, bear in mind, I'm not asking anybody to believe that's true - just to 
acknowledge that it's possible and therefore a reasonable question to ask.

There is no confusion on my part about the role of complexity.  I don't think 
that complex organisms are necessarily better adapted and have never suggested 
they are (I only suggested that on the axis of complexity we have seen 
progress, not that increased complexity necessarily makes an organism better 
adapted for its environment)

Liz, I've never suggested that the process would be linear.  In fact, I've 
never even suggested that I think organisms are better adapted to their current 
environments than ancient organisms were to theirs.  I've only asserted that it 
is not a nonsensical question.  The fact that we keep coming back to the 
argument that 'environments are constantly changing therefore organisms are 
always trying to catch up with the changes' implies that, in fact, organisms 
could end up better adapted to their environments.  Implicit in your statement 
'...environment that 'shapes' them also changes through time.' is that if the 
environment didn't change through time that we would see a trend towards 
organisms that were better adapted for their environment.  If that's true, then 
why would we assume that somehow the changes in the environments occur at a 
rate that is perfectly synchronized with the rate at which a population evolves 
and so how well organisms are adapted to their environment stays constant?  
That just seems extraordinarily coincidental.  What I could believe is that at 
different times in history organisms have been more or less adapted to their 
environments but on average they are no better adapted today than they were in 
the past.  But. I can't see that there is anything that necessarily makes that 
true.

Best, Jeff H.


________________________________________
From: Mitch Cruzan [cru...@pdx.edu]
Sent: December 7, 2012 3:03 AM
To: Jeff Houlahan
Cc: ECOLOG-L@LISTSERV.UMD.EDU
Subject: Re: [ECOLOG-L] Discussion Panel Topic Suggestions

Hi Jeff, Joey, and all the rest.
    I think several people have expressed a core principle of the
misunderstanding of evolution - I will try to explain.  Some 3 billion
years ago the Earth was occupied by organisms that were certainly
simpler than many extant species, but they were also just as well
adapted to their environments as anything existing today.  The
confusion, I think, comes from equating complexity with improvement, but
that is not the case.  As others have stated, some of the most
successful organisms are also some of the least complex.

    So where does complexity get us?  The answer is - probably just to
novel ways of resource acquisition.  In a Precambrian world (the time
that Jeff referred to), the main difference compared to later was that
the number of trophic levels was limited.  There were photosynthetic
autotrophs and "herbivores" that fed off of them, but the evolution of
larger "predators" required an increase in complexity.  The important
thing is that all of the species from that time period were subjected to
strong selection so they were as "adapted" to their environments as
anything you would find today.

    The problem is the meaning of "better" - not a word in the
evolutionary vernacular.  In evolution different species can't be
compared as better or worse - they just succeed or they are replaced by
others.  No species will persist forever - the ultimate fate of any
lineage - even Homo sapiens - is extinction. At least 99% of all species
that have ever existed are now extinct, and not because they were
replaced by improved species - it was often just by chance.  The process
of species turnover through time is generally not as dramatic as mass
extinctions in response to global disasters, but more often it is a
replacement - things change until they are eventually different enough
that they could not have reproduced with their ancestors.  I know you
are going to say "what about cockroaches or cycads, haven't then been
the same for 100's of millions of years?"  No, not really - only
superficial based on what we can tell from fossils, but the cockroach of
old ages is not the same as the ones we have today.

    On the other hand, it is important to realize that species are not
adapted to their environments because there are many forces constraining
them.  These include:
1.  Environments change in unpredictable ways.  Studies of selection in
nature often show that is changes from one season to the next - species
are chasing (actually, being pushed towards) a moving target.
2.  Gene flow from other populations.  The effects of selection can be
swamped are at least constrained by dispersal of individuals and spores
(pollen) from populations that are subjected to different selection regimes.
3.  Random effects of genetic drift - do not underestimate the power of
drift to overcome selection and gene flow.
4.  Evolutionary constraints - genetic correlations among traits due to
developmental pathways, life history tradeoffs, and physical constraints
may prevent a population from responding to selection.
5. Lack of adequate variation - the right mutations or combinations of
alleles at different loci may not have appeared just yet, or not in the
right combination in any individual.

The upshot is that populations and species are never adapted to their
environments.  It is important to remember that these environs that we
view as stable - these habitats we try to "conserve" - are dynamic.
They are destined to undergo change and attempting to constrain them
from that would create unnatural conditions.  The world has changed a
lot in the last 10,000 years and most species have not had a chance to
catch up - probably never will because things continue to change.

My advice to all who wish to engage in this panel is to head to your
nearest used textbook outlet and pick up an older edition of any
introductory evolution textbook.  The classic is the one by Doug
Futuyma, but there are many new versions by other authors as well.  For
anyone with a few years of biology under their belts including
introductory genetics, cell biology, molecular biology, and intro
ecology,  this subject material should be pretty accessible.

Mitch Cruzan


On 12/6/2012 5:17 PM, Jeff Houlahan wrote:
Hi Joey, I am not arguing that evolution has led to progress on some axis - 
that's an empirical question. I am only arguing that it is not a 
misunderstanding of evolution by natural selection to suggest that it is 
possible.  You've stated conclusively that evolution by natural selection 
cannot lead to progress.  So, if I could provide empirical evidence that, on 
average, current organisms are better adapted to their environments than 
organisms were 3,000,000,0000 years ago would you still deny that was progress? 
 I'm OK with that but it's just a semantic issue then - something that I would 
be willing to call progress you wouldn't be willing.  On the other hand, if 
you're saying that it's not possible that over time time organisms have become 
better adapted to their environments then our difference of opinion is more 
fundamental. But, keep in mind - this is not a debate about whether evolution 
by natural selection HAS resulted in progress, it is about whether it's 
reasonable to ask the question, has evolution resulted in progress?  Just 
because the answer might be no doesn't mean the question doesn't make sense.
And what about the example from Lenski's work - he has absolutely demonstrated 
in his population of E. coli that later generations were more fit than earlier 
generations.   The population that had been around longer was better adapted. 
Why would it be possible over 75,000 generations of E.coli but not possible as 
a general rule?
The problem I have is not that you believe that evolution by natural selection 
has not resulted in better adapted organisms - it's that you believe that 
anybody who suggests it's possible, misunderstands evolution by natural 
selection.  Best, Jeff Houlahan


________________________________________
From: Ecological Society of America: grants, jobs, news 
[ECOLOG-L@LISTSERV.UMD.EDU] on behalf of Joey Smokey 
[northwestbird...@gmail.com]
Sent: December 6, 2012 7:24 PM
To: ECOLOG-L@LISTSERV.UMD.EDU
Subject: Re: [ECOLOG-L] Discussion Panel Topic Suggestions

Ecolog:

I would like to commend Wayne for his devil's advocate approach to
suggesting the third question and starting this discussion. It seems my
original interpretation was correct: the whole purpose of the question was
to dispel the misconceptions around the semantics of evolution.

I find it interesting how several of you use the word "progress" in
different contexts, and I especially like the idea of defining progress
along some sort of axis, such as increasing complexity. This all being
said, I do have some retorts. Firstly, if the argument is to be made that
evolution leads to increasingly complex life forms, it should be noted that
this has happened many times in evolutionary history. Adaptive radiations
and mass extinctions produce a cycle of "simple-to-diverse" organisms over
millenia. However, at the end of every mass extinction, the diversification
of organisms and their niches is eliminated, and complexity of life is
severely reduced. So, given our idea of progress, however you want to
define it, you still cannot use it. If organisms did in fact progress over
whatever axis you'd like to use, then despite mass extinctions they would
continue to become more and more advanced. We are currently in the middle
of an anthropogenic mass extinction, whether or not some folks want to
accept that, and at the end of it, the complexity of life as we know it
will vanish. Fact: prokaryotes have remained simple unicellular organisms
for billions of years for a reason. :)

To the point of evolution of individuals, populations, and communities:
Individuals and communities do not evolve. I think the idea of community
evolution has been sufficiently put the rest already. To use semantics
correctly: natural selection acts on individuals and has consequences on
allelic frequencies in populations. One individual organism cannot evolve,
because its allelic frequency never changes throughout its life. But,
natural selection can cause it to influence the allelic frequency of future
generations in the population, and that -is- evolution. Also, when folks
use the terms of "fittest" and "survival of the fittest", etc., that should
be avoided. The four postulates of natural selection lead to relative
fitness. In other words, one individual can only have a slightly higher
fitness than another. Liz already alluded to this; and I also quite like
her noting that even our own species is by no means "perfect."

Recapping: Evolution is not directional. Evolution is not perfect. And
evolution does not lead to the good of the species (example: infanticide).
Evolution leads to organisms being well-adapted to their environment at a
specific time. Temporal environmental changes (i.e. climate change) lead to
organisms no longer being well-adapted to their environment, and they must
either adapt or face extinction.

Regards,

Joey Smokey
WSU Vancouver


On Thu, Dec 6, 2012 at 12:31 PM, Jeff Houlahan <jeffh...@unb.ca> wrote:

Hi all, admittedly evolution by natural selection has no goal - it just
happens. But, the logical outcome of natural selection is a population
containing fitter organisms.  Richard Lenski's experiments have shown
conclusively that the E. coli in his cultures that have evolved for longer
are fitter (using competitive ability as an index of fitness).  If we can't
call that 'progress' then we've put some pretty narrow constraints on the
word progress and presumably progress can only be used in human contexts
where there are explicit and clearly defined goals.  OK. But that just
means we need to rephrase the question to avoid the use of the word
progress (although it's the same question, I think) - as we move from the
first living organisms to the current group of living organisms, have
living organisms, on average, become better adapted to their environments?
   I don't know if this is a testable question but it doesn't seem like an
illogical one.  And I have to confess, I see it as semantic hairsplitting
to be unwilling to talk about 'better adapted to their environment' as
progress.  Best, Jeff Houlahan.


________________________________________
From: Ecological Society of America: grants, jobs, news [
ECOLOG-L@LISTSERV.UMD.EDU] on behalf of Rachel Bolus [r...@bio.umass.edu]
Sent: December 6, 2012 2:15 PM
To: ECOLOG-L@LISTSERV.UMD.EDU
Subject: Re: [ECOLOG-L] Discussion Panel Topic Suggestions

Hello
I think that the interesting debate generated by the issue of
"evolutionary progress" is exactly why it's a good topic for this panel.
It makes people think carefully about definitions and the processes. I
also think that Chris Edge just hit the nail on the head about our
misuse of the word "progress." "Progress" or "advancement" suggests
teleology, which has been largely rejected by evolutionary biologists.

One of the reasons why we stumble over the question, "Do organisms
advance over time?" is that we confuse complexity with progress. Yes, on
average, organisms become more complex over time, because the process of
evolution is the accumulation of changes in traits of individuals in
populations over time. Although losses are part of this process, gains
are added on top of previous gains, resulting in more complexity
(especially in the multi-celled organisms that more frequently catch our
eye).

Is complexity progress? As humans, our intuition tell us, "yes" because
we like shiny complex things (perception bias, perhaps?). If we are
handed two tablets, one that is a chalkboard and one that is an iPad, we
know which one we think is better. But when the flood comes, which one
is still functional afterwards? Adaptation results in organisms fitting
their environment better, but the more adapted we are to a particular
environment, the less flexible we are to change. In a large time scale,
flexibility should trump complexity. Sometimes more complex things are
better able to adjust to changes in the environment, sometimes they
aren't. In a "stable" environment (if it exists) what organism is best
able to survive and reproduce may be complex or may be simple.

What is "better" is largely subjective- is it complexity, adaptation
(resistant microbes!), size (currently, blue whales!), intelligence
(humans!), ability to produce the most offspring and biomass possible
(fungi!), ability to persist relatively unchanged across epochs
(sponges!)... ?

As an interrelated topic (the previous one is mostly evolutionary, with
ecology included as part of the process of adaptation), it might be fun
to include the changing ideas of forest succession (getting back to the
issue of "Do communities evolve?"). Previously, it was thought that
forest communities progressed towards climax stages, but now we realize
how patchwork, stochastic, and cyclical this process is.

Rachel Bolus
Ph.D. Candidate
Organismic & Evolutionary Biology
University of Massachusetts Amherst

On 12/6/2012 10:03 AM, Chris B. Edge wrote:
Hello all,
I have spent some time thinking about this topic over the last several
years. As a relatively 'green' evolutionary ecologist I rarely enter
these
debates in public forums.
My opinion's are heavily influenced by Jared Diamond's writing on the
topic. In not as eloquent words 'progress' implies that there is a goal
or
target that evolution is moving towards. Of course we can define the goal
or target post hoc, complexity, invasion of terrestrial habitats, etc.
and
conclude that evolution has made progress. However non of these
goals/targets apply to all organisms or habitats, and non of them can be
defined a priori.
'Progress' may capture the essence of the message we want to get across
it
is not a good word to use to describe major evolutionary trajectories
unless the statement it is used in also includes the axis or scale
progress
is to be measured on. Instead major trajectories should be described as
they are, observed trajectories/trends. For example, consider these two
statements; 1) 'evolution has resulted in a trend of increasing
complexity', and 2) 'evolution has made progress towards increasing
complexity'. The two statements convey the same message, but statement 2
implies that complexity is always good. In my opinion statement 1 is much
better.
Regards,
Chris Edge

On Wed, Dec 5, 2012 at 11:40 PM, Wayne Tyson <landr...@cox.net> wrote:

Ecolog:

Pryde is right on. But the reality is that evolution is misunderstood
by a
lot of people, and clarity on this subject would go a long way toward
resolving some of the conflict arising therefrom. That will require
clear
statements from evolutionary biologists for starters, and perhaps a lot
of
article-writing and TV production that not only is more careful about
the
semantics used,* but actually getting the ball rolling toward rolling
back
the misconceptions.

But first, you catch the rabbit--and even make the stew. Then serve it
until it is found delicious. (As long as it's not bushmeat.) That is,
get
this matter thoroughly discussed by evolutionary biologists and others
who
understand the merits and deficiencies of the two "sides," then "make it
news."

WT

*advancement, progress . . .
     ----- Original Message -----
     From: Liz Pryde
     To: Wayne Tyson
     Cc: ECOLOG-L@LISTSERV.UMD.EDU
     Sent: Wednesday, December 05, 2012 9:00 PM
     Subject: Re: [ECOLOG-L] Discussion Panel Topic Suggestions


     In Darwin's "Origin" the theory was one of adaptation, not
advancement.
     Unfortunately Spencer coined the "fittest" remark and that was a
popular
mode of thinking at the time - when people were rather
self-congratulatory
about their scientific understandings of the natural world (how
clever!).
     So, evolution was originally meant as an adaptation to the chance
environment. It may or may not have been 'better' than the previous
model,
but it survived through chance, and we assume, advantage. This doesn't
necessarily make it advantageous throughout time.


     I'm sure we can all come up with improvements to the human body ;).
     Liz






     On 06/12/2012, at 2:47 PM, Wayne Tyson <landr...@cox.net> wrote:


       Joey and Ecolog

       I am the author of question 3, and the point is exactly the one
made
by Smokey, with which I fully agree. There do seem to be people who
seem to
be of the opinion that evolution IS progress, however. I posted this
question to a well-known evolutionary biology forum and Richard Dawkins
replied in the affirmative; when I asked for further clarification,
there
was no response (except one which agreed with my point; several others
were
outraged, and I ended up having to issue an "apology." David
Attenborough,
in one of his excellent TV programs used the term "advance," in
discussing
the matter with one of the world's top paleontologists, whom I emailed
the
raw question; he responded in the affirmative, that the creatures he was
most famous for studying did "advance." When I responded by asking if he
would then conclude that the genus Homo would then be an example of
"evolutionary advance," the correspondence was terminated.

       My straw polling amongst "the public" tilts strongly in favor of
"progress" or "advancement" with time, and while I'm not sure of all the
sources that have contributed to this impression, the Time-Life book
"Human
Evolution," with its famous/infamous "March of Progress" illustration
beginning with a quadruped ape and ending with an upright, apparently
Aryan
male. I know of no studies that have been done on this issue, and
attempting to raise the discussion on respected websites causes more
blowback than the kind of clarity that Smokey's concise statement
brings to
the discussion.

       Ecolog is a respected and large listserv. Will there be further
comments, either in support or in refutation of Smokey's explanation,
or is
this subject one of those academic "third rails" that no one dare touch?
Those who fear posting their comments here could send Smokey and me
their
comments directly if they want to avoid reprisals (the subject of
reprisals
for posts reared its ugly head several months ago, and believe it or
not,
the emails I received were not limited to students; I got several from
professors).

       On the other hand, if this subject is considered unimportant,
"proper"
actions can be taken, eh?

       WT

       ----- Original Message ----- From: "Joey Smokey" <
northwestbird...@gmail.com>
       To: <ECOLOG-L@LISTSERV.UMD.EDU>
       Sent: Tuesday, December 04, 2012 1:51 PM
       Subject: Re: [ECOLOG-L] Discussion Panel Topic Suggestions



         Jason,

         I strongly advise against the third question. Evolution is not
directional,
         and the question is worded to suggest that it is. If the point
of the
         question is to dispel the idea of evolution being directional,
then
it
         would be fine.

         There are many common misconceptions of organisms "progressing"
through
         evolution. The most common is the typical classroom image of
human
         evolution moving from ape-like toward human-like over time.
Transition
         species in the fossil record do not suggest a progressive change
from one
         type of body form into another. The transition to terrestrial
life
is the
         same way; transition species such as Tiktaalik, Eusthenopteron,
and
         Ichthyostega did not "march along" until they were well-adapted
for
life on
         land. Evolution does not craft "improved" species or "advanced"
species. It
         simply results in organisms being well-adapted for their
environment
at a
         given time.

         In regards to the fourth question, ecological time refers to
immediate
         interactions between organisms and their environment. It does
lead
into
         evolutionary time and the change in allelic frequencies through
         generations. So, ecological interactions can and do have
meaningful
impact
         on evolutionary trajectories of species.

         I think the first two questions will lead into some good
discussion.
         Best of luck on your discussion panel,

         Joey Smokey
         WSU Vancouver


         On Tue, Dec 4, 2012 at 8:37 AM, jason.strickland <
         jason.strickl...@knights.ucf.edu> wrote:


           Dear group,

           I have compiled some of the ideas that were given to me about
my
           discussion panel. The response was much lower than I expected
so
if you
           have any ideas, feel free to share those as well. Thank you to
all
those
           that contributed.


           1.       Will most organisms be capable of adapting quickly
enough
to
           respond to climate change/sea level rise to be evolutionarily
relevant?

           2.       What impact will Genetically Modified Organisms have
on
the
           ecology and evolution of the modified species and other
species?
           3.       Do organisms progress/improve/advance through
evolution?
           4.       Do ecological processes/interactions last long enough
to
have any
           meaningful impact on the evolutionary trajectory of a species?

           Please share your thoughts on these topics or suggest others.

           Cheers,
           Jason Strickland
           jason.strickl...@knights.ucf.edu

           From: jason.strickland
           Sent: Tuesday, October 30, 2012 3:59 PM
           To: ECOLOG-L@LISTSERV.UMD.EDU
           Subject: Discussion Panel Topic Suggestions

           Dear group,

           I am currently working on forming a discussion panel that will
include two
           ecologists and two evolutionary biologists to discuss topics
that
involve
           merging ecology and evolution. The discussion will be in front
of
150-200
           students ranging from undergraduates to post-docs (all in
biology). The
           panel will happen on a Saturday morning so it needs to be an
exciting
           discussion to hold the audience's interest and cause them to
ask
questions.

           I am looking for topics/questions that the two fields do not
completely
           agree on. The goal is to have the panel disagree on topics to
allow the
           students to learn and be entertained. If anyone can suggest
topics
or
           questions that ecologists and evolutionary biologists have
different
           viewpoints on, they would be greatly appreciated. I have a few
topics
           already, but wanted to ask a larger audience to suggest topics
to
determine
           if there are certain topics/questions that come up frequently.
Feel free to
           email me directly (jason.strickl...@knights.ucf.edu<mailto:
           jason.strickl...@knights.ucf.edu>) or respond to this post
with
your
           suggestions.

           Thank you in advance for your help,

           Jason Strickland
           jason.strickl...@knights.ucf.edu<mailto:
jason.strickl...@knights.ucf.edu>




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     Liz Pryde
     PhD Candidate (off-campus @ The University of Melbourne)
     School of Earth and Environmental Sciences
     James Cook University, QLD

     elizabethpr...@gmail.com
     epr...@unimelb.edu.au







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--
Ph.D. Candidate
Organismic & Evolutionary Biology
University of Massachusetts Amherst
219 Morrill Science Center South
Amherst, MA 01003