Based on my studies in invasive species, I would say the question of
whether there are sharp transitions, or more gradual changes, should be
rephrased. You allude to it in your explanation, but it appears there
are both. I think the relevant question is -- under what conditions
does one or the other process (sudden or gradual) occur and then prevail?
Teresa
Teresa M. Woods, Ph.D. Candidate
Coordinator
Olathe Educational Partnership
K-State Olathe Innovation Campus, Inc.
18001 West 106^th Street, Suite 130
Olathe, KS66061-2861
913-541-1220
Mobile: 913-269-8512
On 11/14/2010 10:49 AM, Pekin, Burak K wrote:
The idea that there is a "moment when one species evolves into another" is
interesting. Does the evolutionary lineage of species consist of sharp transitions, or
more more gradual changes from one species to another?
In ecological biogeography, the change in the relative dominance of species
across a landscape can be sharp or gradual. Sometimes we see that one species
is replaced by another over a very short distance due to a physical barrier or
an abrupt change in key environmental factors. Other times, we see that the two
species co-exist over large distances and the relative dominace between the
species changes across a gradual environmental gradient. In the latter case, it
is more difficult to define a point in space in which the change in dominance
occurrs.
Are evolutionary processess over time analogous to 'environmental gradients'
over space? If so, what kinds/aspects of evolutionary processess determine the
sharpness/gradualness of the switch from one species to another? What role does
the inherent genetic structure of particular species play in determining the
gradualness of this switch?
Perhaps the reason the definition of what constitutes a species is 'fuzzy'
because the processes that control the change of one species to another are
unclear. Ecologists often try to define species according to their functional
attributes inorder to access their ecological significance in ecosystems.
Similiarly, the 'species' of an organism should correlate with a function/s
inherent to its genetic code, which in turn has some evolutionary significance.
However, in this context at least, taxonomic science is a lot less definitive
than ecological science, as it is quite lacking in knowledge of the links
between the genetics of individual species and thier evolutionary heritage.
------
Burak K. Pekin, Ph.D.
Postdoctoral Research Associate
Department of Forestry and Natural Resources
Purdue University
________________________________________
From: Ecological Society of America: grants, jobs, news
[[email protected]] On Behalf Of Warren W. Aney [[email protected]]
Sent: Sunday, November 14, 2010 12:27 AM
To: [email protected]
Subject: Re: [ECOLOG-L] Taxonomy and Ecology Integrating or Disintegrating?
I suspect taxonomists consider their science more rigorous than some of the
other biological sciences, particularly ecology. After all, isn't a species
an absolute thing to be definitively described and classified, whilst an
ecoregion is a loosey-goosey entity with a definition more or less dependent
on the describer's perspectives and whims?
But then there are the century long disputes between the taxonomic splitters
and the taxonomic lumpers. Did we once have 4 species of the now-extirpated
grizzly bear in Oregon, as the early 20th century taxonomists had it split?
Or did we have just one subspecies of the circumboreal brown bear as the
lumpers now have it? And how was the decision made that recently
reclassified the Oregon junco and several other Pacific Northwest species
into one species -- the dark-eyed junco? Was it a more defensible decision
than the splitters' original classifications, or was it based mostly on a
subjective redefinition of what a species is?
So isn't part of this dependent on how taxonomists define what a species is?
We know it's not as simple as the old standard: "A set of organisms that
does not viably breed with another set of organisms." Even the dictionary
(Webster's New Word College Dictionary, Fourth Edition) uses subjective
verbage such as "similar organisms" that "usually interbreed" in defining
the biological term.
Maybe taxonomists should stick to labeling species with objective rigor
instead of labeling other scientists with snobby scorn. Both of our sciences
are evolving, just as species evolve. And will taxonomic science be able to
catch the moment when one species evolves into another, or is that process
just too fuzzy?
Warren W. Aney
Senior Wildlife Ecologist
Tigard, Oregon
-----Original Message-----
From: Ecological Society of America: grants, jobs, news
[mailto:[email protected]] On Behalf Of Wayne Tyson
Sent: Saturday, 13 November, 2010 18:40
To: [email protected]
Subject: Re: [ECOLOG-L] Taxonomy and Ecology Integrating or Disintegrating?
I could only take this person's word for it. The interpretation I came away
with was that it was something akin to stamp collecting, but I suspect that
part of the story might be that taxonomy is taxing enough in itself without
being overly concerned with ecology and evolution. It was the apparent
disdain with ecology and the ecologists (plant geographers?) who determined
the ecoregion boundaries that caught my attention most.
As to entomologists, my own observations have left me with the impression
that they know more about plants than botanists do about "bugs."
WT
----- Original Message -----
From: "Charles Stephen"<[email protected]>
To:<[email protected]>
Sent: Saturday, November 13, 2010 10:30 AM
Subject: Re: [ECOLOG-L] Taxonomy and Ecology Integrating or Disintegrating?
Why would he care about compiling a checklist of a region if he was not
interested in geographical patterns of species distributions?
If it's pure nomenclature that he cares about, surely teaching-quality
samples with no locality info would suffice. For that matter, why bother
looking at real organisms at all - why not just search through the
botanical
nomenclature tomes and correct invalid names?
Seems crazy to me. I - not that I'm that particularly advanced in my
career
- view ecology as an integrative approach that has access to many tools
for
answering research questions. Taxonomy is one such tool, and is a
descriptive science (which is ok!) that builds the foundation for
integrative disciplines, like ecology and systematics. It's essential to
get the names right, otherwise what beans are you counting, really, and
shouldn't you have an ethical problem with convincing people about
patterns
or making laws based on the relative amounts of the different beans you've
found?
My experience to date has been with ecologists who believe in the value of
taxonomy, so I've yet to witness any schism. But then maybe I've just
been
lucky. :)
Cheers,
Charles
--
Charles Stephen
MS Entomology student
email: [email protected]
cell phone: 334-707-5191
mailing address: 301 Funchess Hall, Auburn University, AL, 36849, USA
On Fri, Nov 12, 2010 at 5:18 PM, Wayne Tyson<[email protected]> wrote:
Honourable Forum:
Recently there was a discussion about the importance of getting
nomenclature right in ecological studies. The general conclusion was that
this is important. To me, the implication was that ecologists need
taxonomists on the team (this may or may not always or even rarely be
possible), or at least a procedure by which taxonomic accuracy can be
assured.
I recently attended a lecture by a botanist of regional and international
repute who described a large project to compile a checklist of the
vascular
flora of an inadequately-explored, but quite large region. It is
undeniable
that this is important work, and through this person's leadership,
significant additions to knowledge of the area have been made. The
lecture
included maps of "bioregions" or "ecoregions." This botanist dismissed
the
value and importance of them, adding that they were the province of the
ecologists and were highly flawed (I can't quote the lecturer precisely,
but
this is the best of my recollection and my distinct impression). The
lecturer essentially dismissed ecology, remarking that the lecturer was
interested only in individual plants and seemed contemptuous of
ecologists
in general, and particularly those involved in establishing the
ecoregions
that were a part of the lecture. I may have misunderstood, as I have long
held this person in high regard, and those remarks seemed inconsistent
with
past behavior.
Do you find this state of mind to be common among taxonomists in general
or
botanists in particular? Is this apparent schism real or imaginary? Other
comments?
WT
PS: During the lecture, the speaker remarked about ecological phenomena
which were not understood (no clue), but at least one reason for one
phenomenon was apparent to me. I said nothing, as the lecture had been
very
long and the question period short.
----------------------------------------------------------------------------
----
No virus found in this incoming message.
Checked by AVG - www.avg.com
Version: 8.5.449 / Virus Database: 271.1.1/3254 - Release Date: 11/13/10
07:34:00
