[Taxacom] Oceanic dispersal vs. vicariance

[John Grehan]

Jason,
Thank you for taking the time to outline some of your views. Comments
inserted below:

 “John & Michael, I am familiar with the literature although it is
always useful to ask for a working definition of what the other person
is thinking, since such things tend to be fluid over time.”
OK

“I can´t understand what you mean. Anybody who is familiar with the
biogeography literature since the 70´s knows that vicariance has
reigned supreme during most of this time.”

Vicariance certainly gained popularity during the1970’s but most
biogeographers continued to promote Darwin’s center of origin and dispersal
model.

“ It has been a case of developing the appropriate framework to test both
mechanisms (area cladograms, molecular phylogenetics, ...),
As noted at various points in the discussion, molecular phylogenetic has
not tested vicariance. Area cladograms are one way of looking at allopatry
in relation to phylogeny and geography. Not sure it constitutes a test, but
maybe others see that differently.

“ with the pendulum swinging but staying primarily over vicariance.”
Not so sure about that.

“By applying a Panbiogeographic orthodoxy you eventually reach the
point where the inconsistencies and the stretching of facts pushes you
to make rather extraordinary claims such as the existence of monkeys
in the lower Cretaceous.”

Or maybe the claim for monkeys in the lower Cretaceous is not so
extraordinary at all. And perhaps there are no such inconsistencies and
stretching of facts. But need specifics to address that.

“This requires that we stretch most crown lineages well into the L
Cretaceous or U Jurassic, a time when all you get are a few fossils of
non-crown mammals or some dubious monotremes.”

‘Everyone’ says the fossil record is incomplete, then in the same breath
say it is sufficiently accurate. Most species don’t even have a fossil
record at all.
“Are you saying that all mammalian lineages have the same gap in the
fossil record of many tens of millions of years (50-70my)?”

According to what I see of the biogeography, yes.

“What is your evidence for making this claim other than it being necessary
to fit the phylogeny on to tectonics?”

You put the words in my mouth – that it is necessary to fit the phylogeny
onto tectonics when that is not the case at all.  The evidence lies in both
the spatial correlation of distributions with each other and the tectonic
correlations of allopatric distributions.

“I expect extraordinary evidence in order to accept this and so far it is
not forthcoming.”

If you say that something is not acceptable unless it constitutes
‘extraordinary’ evidence then you might be setting yourself up for
disappointment. Creating criteria of personal acceptance and judging
everything by that is a personal decision only. has. When it was pointed
out that the existence of a major tectonic formation at the Galapagos was
predicted from biogeography before the geological discovery one might say
that this was quite extraordinary. Others just said pigs could fly.

“Saying that  "fossils are just minimum ages" is one thing, but accepting
on faith that all the fossil evidence is short by half is quite another”.

What we have is a situation where biogeography predicts certain ages for
taxa that precede their fossil record. Because fossils set minimum ages the
earlier predictions are not contradicted by the fossil record.

“I see no point in pressing you on dung beetle biogeography since your
replies indicate you can´t or won´t offer useful input.”

Sorry that the input was not useful. I just responded to your assertions.
Did you want me to do a spatial analysis of your group? Did you want me to
convince you of something?

However I must reiterate my query regarding Inachis io and D. plexippus as
I am curious to know if this is "normal" dispersal or not.
Species have distribution ranges which are maintained, expanded, or
contracted by the ordinary means of dispersal. So yes.

“Because you see, the idea that: "Normal dispersal is seen every day ...,
and takes place by normal, observed means of dispersal." is strange. What
is normal? The dispersal distance observed everyday, month, year,
decade..., which? Unassisted by wind, or currents or hitching a ride
on other organisms? Are a few tattered butterflies arriving to the
coast of a distant land after and oceanic crossing an example of
"normal" dispersal? Winning the lottery is not normal, but it happens,
you just need to buy tickets and if you buy lots of tickets or play
for long enough you have a fair chance of winning.”

It’s a normal ecological process that plays a role (along with local
extirpation) in the maintenance of distributions

"This then brings us to the second point where you assert that "This
sort of dispersal does not lead to speciation." I am assuming here
that you use the expression as a sort of short-hand (and rejection) of
peripatric speciation. "

In general speciation is allopatric (that's from the biogeographic
evidence). I would see peripatric speciation as a form of allopatric
differentiation.

“This implies that you consider barriers to be either completely porous
(normal dispersal) or completely impermeable (long distance dispersal,
LDD). “
What is usually presented as evidence for LDD is not. If LDD (as in a
process that leads to differentiation) occurs then fine.

“The evidence that is available, as far as metapopulation studies is
concerned, demonstrates a spectrum which depends on each lineages inherent
ability and, yes, luck. Also the relative permeability of a barrier is
fluid in time.”

Yes, agree in general principle. Although whether barriers exist
operationally in the way they are perceived is for me a more difficult
question.

“A growing ocean between two plates becomes gradually impermeable for all
except the most mobile taxa, but the process is gradual and may not be
entirely effective as per the examples provided above (and others I have
provided).”

Sure, wide ranging species may range wider than a particular habitat gap,
whether an ocean or anything else.

“If so it boils down to an issue of semantics when distinguishing between
"normal" and LD dispersal, except as a subterfuge.”

Of course I would disagree with that. But I do not begrudge you your
conclusion. You are welcome to it.

Regards,

John Grehan


On Mon, Jun 18, 2018 at 8:52 PM, JF Mate <aphodiinaemate at gmail.com> wrote:

> Thanks Daniel. It certainly has become a lousy debate, and although I
> am pushing the patience of other taxacomers, and Ken is much wiser
> than me in letting this whole affair go, forgive me if I give it one
> more go before abandoning the enterprise altogether. Apologies if this
> last post on the topic sounds somewhat crabby.
>
>  John & Michael, I am familiar with the literature although it is
> always useful to ask for a working definition of what the other person
> is thinking, since such things tend to be fluid over time.
>
> When you say that "The prominent 'debate' (and suppression of) over
> vicariance has been around now for about 40-50 years now (also in
> existence earlier, but suppression of the subject was pretty much
> total) and likely to continue for some indefinite time in the future,
> despite some expressions of frustration in the literature that the
> vicariance approach has been 'falsified' and should just go away,
> disappear etc."
> I can´t understand what you mean. Anybody who is familiar with the
> biogeography literature since the 70´s knows that vicariance has
> reigned supreme during most of this time. It has been a case of
> developing the appropriate framework to test both mechanisms (area
> cladograms, molecular phylogenetics, ...), with the pendulum swinging
> but staying primarily over vicariance.
>
> By applying a Panbiogeographic orthodoxy you eventually reach the
> point where the inconsistencies and the stretching of facts pushes you
> to make rather extraordinary claims such as the existence of monkeys
> in the lower Cretaceous. This requires that we stretch most crown
> lineages well into the L Cretaceous or U Jurassic, a time when all you
> get are a few fossils of non-crown mammals or some dubious monotremes.
> Are you saying that all mammalian lineages have the same gap in the
> fossil record of many tens of millions of years (50-70my)? What is
> your evidence for making this claim other than it being necessary to
> fit the phylogeny on to tectonics? I expect extraordinary evidence in
> order to accept this and so far it is not forthcoming. Saying that
> "fossils are just minimum ages" is one thing, but accepting on faith
> that all the fossil evidence is short by half is quite another.
>
> I see no point in pressing you on dung beetle biogeography since your
> replies indicate you can´t or won´t offer useful input. However I must
> reiterate my query regarding Inachis io and D. plexippus as I am
> curious to know if this is "normal" dispersal or not. Because you see,
> the idea that: "Normal dispersal is seen every day ..., and takes
> place by normal, observed means of dispersal." is strange. What is
> normal? The dispersal distance observed everyday, month, year,
> decade..., which? Unassisted by wind, or currents or hitching a ride
> on other organisms? Are a few tattered butterflies arriving to the
> coast of a distant land after and oceanic crossing an example of
> "normal" dispersal? Winning the lottery is not normal, but it happens,
> you just need to buy tickets and if you buy lots of tickets or play
> for long enough you have a fair chance of winning.
>
> This then brings us to the second point where you assert that "This
> sort of dispersal does not lead to speciation." I am assuming here
> that you use the expression as a sort of short-hand (and rejection) of
> peripatric speciation. This implies that you consider barriers to be
> either completely porous (normal dispersal) or completely impermeable
> (lond distance dispersal, LDD). The evidence that is available, as far
> as metapopulation studies is concerned, demonstrates a spectrum which
> depends on each lineages inherent ability and, yes, luck. Also the
> relative permeability of a barrier is fluid in time. A growing ocean
> between two plates becomes gradually impermeable for all except the
> most mobile taxa, but the process is gradual and may not be entirely
> effective as per the examples provided above (and others I have
> provided). If so it boils down to an issue of semantics when
> distinguishing between "normal" and LD dispersal, except as a
> subterfuge.
>
> Jason
>
> On 18 June 2018 at 08:20, Daniel Leo Gustafsson
> <kotatsu.no.leo at gmail.com> wrote:
> > Well, let's be honest and admit that repeated references to nazi
> propaganda
> > and creationism in describing the arguments and evidence of the people
> > you're arguing with isn't typical of all forms of science... More "Makhan
> > style" than "Darwin style", so to speak.
> >
> >
> > Incidentally, to me, this whole discussion is reminiscent of the
> > discussions on the evolution and distribution of certain bird parasites
> > during the mid-20th century. People like Wolfdietrich Eichler would argue
> > that since chewing lice (and certain other parasites) have no free-living
> > stage, their phylogeny should be a mirror image of that of their hosts
> (the
> > so-called Fahrenholz' Rule). Any transmission between hosts was assumed
> to
> > be extremely rare, and have no phylogenetic impact (i.e. it was assumed
> > that lice *never* successfully established themselves on novel hosts).
> This
> > further lead to the assumption that all lice found on a novel host must
> > necessarily be a new species, regardless of whether or not there is any
> > evidence for this. Eichler very clearly stated (in 1943, I think), that
> > it's methodologically more accurate to say "we do not yet know what the
> > morphological differences between these two taxa are" than to say "there
> > two taxa are morphologically identical, so they are the same species".
> As a
> > result, virtually no taxa on any level described by Eichler and his
> > followers can be identified from their descriptions, as host associations
> > was assumed to be "good enough" as a species description.
> >
> > The dogmatism of certain recurring participants of these discussions here
> > are amusingly similar to Eichler's repeated statement that there "are
> *no*
> > documented cases of a species of louse occurring naturally on two host
> > species" -- a statement reinforced by him habitually splitting all lice
> > from multiple host species into host-specific species, often without ever
> > seeing any specimens.
> >
> > Cheers,
> > Daniel
> >
> >
> >
> >
> > On Mon, Jun 18, 2018 at 4:45 AM, John Grehan <calabar.john at gmail.com>
> wrote:
> >
> >> Hi Ken, That's your privilege. No one had to like how I respond. Your
> >> choice. Sometimes I don't like the way you say things either, but I
> ignore
> >> that as irrelevant and do the best I can to respond. Such responses may
> not
> >> always meet the desires of the recipient, but that's life (and science).
> >>
> >> Cheers, John Grehan
> >>
> >> On Sun, Jun 17, 2018 at 10:24 PM, Kenneth Kinman <kinman at hotmail.com>
> >> wrote:
> >>
> >> > Hi Jason,
> >> >
> >> >        I agree.  Your description "instead it all ends in a series of
> >> > zingers written in scripted, telegraphic style" would pretty much
> >> describe
> >> > my views of John's polemics in particular.  Especially when his
> zingers
> >> > involve creationists or Hitler   Thus my reluctance to respond to
> most of
> >> > his e-mails.  I think I will now answer Michael's post instead.
> >> >
> >> >                       ------------------- Ken
> >> >
> >> >
> >> >
> >> > ________________________________
> >> > From: Taxacom <taxacom-bounces at mailman.nhm.ku.edu> on behalf of JF
> Mate
> >> <
> >> > aphodiinaemate at gmail.com>
> >> > Sent: Sunday, June 17, 2018 8:41 PM
> >> > To: Taxacom
> >> > Subject: Re: [Taxacom] Oceanic dispersal vs. vicariance
> >> >
> >> > John, Michael, this isn´t going anywhere. I was waiting for a hint of
> >> > proper debate but instead it all ends in a series of "zingers" written
> >> > in scripted, telegraphic style. I have not seen any ideas presented by
> >> > either one of you that aren´t encapsulated and operationalized in a
> >> > superior manner in cladistic biogeography or evolutionary
> >> > biogeography, sans the unproven axiomatic mania that dispersal doesn´t
> >> > occur. In fact, you don´t seem to to agree on a definition of
> >> > dispersal or if it even occurs (Michael says he doesn´t question
> >> > "slight" dispersal, but you say otherwise). To move the debate towards
> >> > some clear definition of dispersal, I would point to present day,
> >> > observable examples such as Inachis io crossing from Europe to NA or
> >> > Danaus plexippus going the other way. To me these are clear, working
> >> > examples of dispersal, some successful (D. plexippus) others, like
> >> > Inachis io, failing time after time. Neither is a slight jump Please
> >> > think about this carefully before replying.
> >> >
> >> > In regards to the dung beetle fauna of Madagascar, we first have to
> >> > consider the fossil evidence. The oldest known Scarabaeinae fossil is
> >> > of unknown affinity (Prionocephale deplanate, U Cretaceous; Krell,
> >> > 2007). Between this assumed Scarabaeinae fossil and clearly
> >> > identifiable ones we have to jump to the Palaeocene-Miocene, where we
> >> > find ichnofossils (brood balls). This in itself is interesting because
> >> > they are the sort of easily preserved structures we should expect to
> >> > commonly find (actually common in paleosols in SA), but we don´t in
> >> > older deposits, so we must assume that they were either uncommon or
> >> > nonexistent. This doesn´t mean that Scarabaeinae were not found then
> >> > but that lineages that build deep nests with brood balls evolved after
> >> > the K-T. These lineages are also found in Madagascar nowadays
> >> > (Helictopleurus, Onthophagus, Scarabaeus) so their presence there is
> >> > difficult to reconcile with a purely vicariant model, even without
> >> > considering the phylogenetic evidence which have them evolving in the
> >> > Palaeocene.
> >> >
> >> > The Malagasy genera endemic genera (except Onthophagus) that have been
> >> > studied yield the following date estimates:
> >> >
> >> > Arachnodes, Epilissus & Apterepilissus 79-49my
> >> > Nanos & Apotolamprus 24-15my (Wirta, Helena. (2018). Dung beetle
> >> > radiations in Madagascar. )
> >> > Epactoides 30-19my
> >> > Helictopleurus 37-23 (doi.org/10.1016/j.ympev.2008.03.010)
> >> > Scarabaeus 24-15my
> >> > Onthophagus: >3 colonizations (age of entire Onthophagini lineage,
> >> > Palaeocene)
> >> > doi:10.3390/insects2020112
> >> > doi.org/10.1111/j.1096-0031.2006.00139.
> >> >
> >> >
> >> > The Aphodiiinae presents more complex biogeography. The oldest fossil
> >> > (a generalized "aegialid-like" genus from the Lower Cretaceous,
> >> > Cretaegialia) suggests a window that may enable some of the lineages
> >> > to be Gondwanan. However, the "coprophilous" Aphodiini are generally
> >> > assumed to be Laurasian in origin (incorrectly in my opinion but we
> >> > have to refer to the published studies). This in itself, plus their
> >> > assumed recent origin ( <60my; DOI: 10.1016/j.ympev.2003.10.019; the
> >> > oldest fossil evidence is Miocene.), makes it almost impossible for
> >> > the lineage to have been present in Madgascar before its split from
> >> > Gondwana.
> >> > At the level of the subgenera that exist in Madagascar, most of them
> >> > are shared with Africa, even down to species:
> >> >
> >> > Nonendemic subgenera: Aganocrossus (1 nonendemic sp); Blackburneus (2
> >> > nonendemic sp); Koshantschikovius (4 endemic sp); Paradidactylia (1
> >> > endemic sp); Pleuraphodius (1 endemic sp, 1 nonendemic sp);
> >> > Pharaphodius (1 nonendemic sp, 2 endemic sp); Pseudopharaphodius (1
> >> > nonendemic sp); Labarrus (2 nonendemic sp; 1 tramp; 1 endemic sp);
> >> > Mesontoplatys (2 nonendemic sp); Neocalaphodius (1 nonendemic sp);
> >> > Nialaphodius (2 nonendemic sp).
> >> >
> >> > Endemic Malagasy subgenera: Madagaphodius (1 sp); Neoemadiellus (8
> sp).
> >> >
> >> > Bordat, Paulian & Pittino 1990
> >> >
> >> > The other Aphodiinae tribes have varying degrees of endemicity that
> >> > suggest vicariance for some (e.g. Saprosites, Aulonocneminae/i) or
> >> > dispersal for others (Rhyparini). I believe the above examples are
> >> > sufficient to illustrate the point.
> >> >
> >> > Best
> >> >
> >> > Jason
> >> >
> >> > On 12 June 2018 at 23:09, Michael Heads <m.j.heads at gmail.com> wrote:
> >> > > Jason,
> >> > > You write: ''... it  seems that we can all more or less agree that
> >> > timing is
> >> > > the key  difference between both mechanisms, and in that context
> >> > patterns in
> >> > > themselves can´t distinguish either mechanism, so they are not
> >> > informative
> >> > > in this specific instance and we can dispense with tracks
> >> > > and other such pattern searching'.
> >> > >
> >> > > Of course, you are free to ignore distributions if you like. But
> here
> >> is
> >> > > what the author of the most cited bbiogeographic work had to say:
> >> > >
> >> > > "To do science is to search for repeated patterns, not simply to
> >> > accumulate
> >> > > facts, and to do the science of geographical ecology is to search
> for
> >> > > patterns of plant and animal life that can be put on a map".
> >> (MacArthur,
> >> > > 1972: 1).
> >> > >
> >> > > On Wed, Jun 13, 2018 at 8:21 AM, JF Mate <aphodiinaemate at gmail.com>
> >> > wrote:
> >> > >>
> >> > >> Sorry to all for dropping off the map. In particular apologies to
> Ken
> >> > >> for leaving him steadfastly defending the fort on his own. Anyway,
> it
> >> > >> seems that we can all more or less agree that timing is the key
> >> > >> difference between both mechanisms, and in that context patterns in
> >> > >> themselves can´t distinguish either mechanism, so they are not
> >> > >> informative in this specific instance and we can dispense with
> tracks
> >> > >> and other such pattern searching.
> >> > >>
> >> > >> So when you claim that “... much of the opposition on timing comes
> >> > >> from rejection of tectonic correlations that are earlier than the
> >> > >> (minimum) molecular estimates.” you are mistaken. The problem is
> that
> >> > >> if the timing is not in agreement with the tectonic evidence then
> >> > >> vicariance can no longer be a contender for the time being. This is
> >> > >> not a rejection of vicariance but a simple observation that the
> >> > >> evidence available just isn´t´t in agreement and dispersal must be
> >> > >> considered as likely.
> >> > >>
> >> > >> Saying that “To me this is about as feeble as it gets with
> >> > >> biogeography - that  dispersal occurred more than once but left no
> >> > >> evidence. But it happened more than once for sure.” is semantic
> >> > >> footplay posing as scientific rigour. There are limitations and
> these
> >> > >> have always been acknowledged by molecular taxonomists from the
> >> > >> beginning, but not to be used as an underhanded, semantic mallet to
> >> > >> clobber dissent. And therein lies the issue I have with you and
> >> > >> Michael. Nobody is questioning vicariance, you question dispersal.
> So
> >> > >> really, we only need one example of dispersal to invalidate your
> >> > >> epistemological building and that is pushing you to make semantics
> >> > >> your arena with such choice examples as “I do not complain about
> >> > >> molecular estimates of divergence, I only complain about minimums
> >> > >> being misrepresentated as actual or maximal. There is a
> difference!”
> >> > >> or “It only involves the Big Lie about molecular estimates.” Quacks
> >> > >> like a duck and all that.
> >> > >>
> >> > >> You also try to distract the argument by introducing other groups
> that
> >> > >> were not part of the initial discussion. Neither vicariance nor
> >> > >> dispersal are on trial here. They are both generally accepted
> >> > >> mechanisms (except by you two it seems) and the only question
> >> > >> originally posed was, which had a hand in the Platyrrhini, so
> let´s go
> >> > >> back to the Platyrrhini. The available evidence, the research on
> this
> >> > >> topic, is pretty much in agreement with Ken´s assertion. What do
> you
> >> > >> bring to the table to refute this. Claiming that “One can only
> assert
> >> > >> otherwise by the Große Lüge that fossil calibrated molecular
> estimates
> >> > >> are not minimums.” is pure semantics. The burden of proof is with
> you
> >> > >> providing fossil evidence or a new dataset that, when calibrated,
> >> > >> contradicts the previous studies.
> >> > >>
> >> > >> Ken also mentions the Malagasy fauna as having recent elements that
> >> > >> precede its split from Gondwana, and he is correct in this regard
> as
> >> > >> well. There are truly ancient lineages that are vicariant but much
> >> > >> more recent ones that cannot have arrived by means other than
> >> > >> dispersal (e.g. The dung beetle fauna is a combination). That is my
> >> > >> bit of evidence. If you can provide counterfactual evidence that
> can
> >> > >> be profitably discussed then that would be great. Semantics not so
> >> > >> much.
> >> > >>
> >> > >> Have a good one.
> >> > >>
> >> > >> On 11 June 2018 at 05:26, John Grehan <calabar.john at gmail.com>
> wrote:
> >> > >> > Hi Ken,
> >> > >> >
> >> > >> > My comments below.
> >> > >> >
> >> > >> >   “ I've been reading a variety of papers on the debate
> (beginning
> >> > about
> >> > >> > 2005) between Alan de Queiroz (and others) on the one hand and
> >> Michael
> >> > >> > Heads (and others, incl. John Grehan) on the other.  I have come
> to
> >> > the
> >> > >> > conclusion that both sides represent polar opposites in the
> debate
> >> > >> > between
> >> > >> > oceanic dispersal and vicariance.  The truth is probably
> somewhere
> >> in
> >> > >> > between, meaning that both sides are right about some cases, but
> >> wrong
> >> > >> > in
> >> > >> > others.  Not at all surprising. “
> >> > >> >
> >> > >> >
> >> > >> >
> >> > >> > There is no evidence that the ‘truth’ is ‘probably’ somewhere
> >> > inbetween.
> >> > >> >
> >> > >> >
> >> > >> >
> >> > >> > “ Perhaps the strongest case for a large number of oceanic
> >> dispersals
> >> > is
> >> > >> > probably from the African mainland to Madagascar. “
> >> > >> >
> >> > >> >
> >> > >> >
> >> > >> > What is the purported evidence?
> >> > >> >
> >> > >> >
> >> > >> >
> >> > >> > “but there is apparently evidence that some of those dispersals
> were
> >> > >> > along
> >> > >> > island chains that no longer exist.”
> >> > >> >
> >> > >> >
> >> > >> >
> >> > >> > What is the purported evidence?
> >> > >> >
> >> > >> >
> >> > >> >
> >> > >> > “Whether such islands existed or not,”
> >> > >> >
> >> > >> >
> >> > >> >
> >> > >> > Then there is no actual evidence?
> >> > >> >
> >> > >> >
> >> > >> >
> >> > >> > “the debate between the two sides seems to be largely centered on
> >> > >> > molecular
> >> > >> > estimates of divergence (about which Grehan seems to repeatedly
> >> > complain
> >> > >> > ad
> >> > >> > nauseum). “
> >> > >> >
> >> > >> >
> >> > >> >
> >> > >> > That comes across as a misrepresentation (unintentional I am
> sure).
> >> I
> >> > do
> >> > >> > not complain about molecular estimates of divergence, I only
> >> complain
> >> > >> > about
> >> > >> > minimums being misrepresentated as actual or maximal. There is a
> >> > >> > difference!
> >> > >> >
> >> > >> >
> >> > >> >
> >> > >> > “Therefore, my increasing reluctance to respond to his continued
> >> > >> > "baiting".
> >> > >> >
> >> > >> >
> >> > >> >
> >> > >> > ????
> >> > >> >
> >> > >> >
> >> > >> >
> >> > >> > “ If he wants evidence, there is lots of evidence in the
> literature
> >> > from
> >> > >> > many authors (many who seem to be somewhat more objective than
> Alan
> >> de
> >> > >> > Queiroz).  “
> >> > >> >
> >> > >> >
> >> > >> >
> >> > >> > Then state what is the purported evidence. No good just saying
> so.
> >> > >> >
> >> > >> >
> >> > >> >
> >> > >> >  “The case for oceanic dispersal from Australia (including
> Tasmania)
> >> > to
> >> > >> > New
> >> > >> > Zealand is admittedly even more controversial.  That controversy
> not
> >> > >> > only
> >> > >> > involves molecular estimates of divergence,”
> >> > >> >
> >> > >> >
> >> > >> > It only involves the Big Lie about molecular estimates.
> >> > >> >
> >> > >> >
> >> > >> >
> >> > >> > “but also whether or not New Zealand was completely submerged at
> >> some
> >> > >> > time
> >> > >> > in the mid Cenozoic.”
> >> > >> >
> >> > >> >
> >> > >> >
> >> > >> > This never had legs to begin with and has been generally buried
> by
> >> > >> > geologists and even orthodox biogeographers.
> >> > >> >
> >> > >> >
> >> > >> >
> >> > >> > “ Therefore, I am  playing devil's advocate in suggesting how
> one or
> >> > two
> >> > >> > species of Nothofagus could have rafted from Tasmania to New
> Zealand
> >> > in
> >> > >> > the
> >> > >> > middle of the Cenozoic.  Maybe they did and maybe they didn't,
> but
> >> > both
> >> > >> > possibilities should be kept in mind. “
> >> > >> >
> >> > >> > If there is evidence for rafting then sure, consider it.
> >> > >> >
> >> > >> >
> >> > >> >
> >> > >> > “Given the long-standing debate between Alan de Queiroz and
> Michael
> >> > >> > Heads,
> >> > >> > I find the Nothofagus case the most challenging (even though some
> >> > >> > earlier
> >> > >> > Nothofagus dispersals seem likely to have been due to vicariance
> >> over
> >> > >> > land
> >> > >> > in Gondwana).”
> >> > >> >
> >> > >> >
> >> > >> >
> >> > >> > Nothofagus is not a ‘Gondwana’ group.
> >> > >> >
> >> > >> >
> >> > >> >
> >> > >> > “Nothofagus distribution could be due to a combination of both
> >> > >> > vicariance
> >> > >> > and some cases of more recent oceanic dispersal.”
> >> > >> >
> >> > >> > Or not. But panbiogeography shows clearly that such a combination
> >> does
> >> > >> > not
> >> > >> > have to be invented.
> >> > >> >
> >> > >> >
> >> > >> > John Grehan
> >> > >> >
> >> > >> >
> >> > >> > On Sun, Jun 10, 2018 at 10:25 PM, Kenneth Kinman <
> >> kinman at hotmail.com>
> >> > >> > wrote:
> >> > >> >
> >> > >> >> Hi all,
> >> > >> >>
> >> > >> >>        I've been reading a variety of papers on the debate
> >> (beginning
> >> > >> >> about 2005) between Alan de Queiroz (and others) on the one hand
> >> and
> >> > >> >> Michael Heads (and others, incl. John Grehan) on the other.  I
> have
> >> > >> >> come to
> >> > >> >> the conclusion that both sides represent polar opposites in the
> >> > debate
> >> > >> >> between oceanic dispersal and vicariance.  The truth is probably
> >> > >> >> somewhere
> >> > >> >> in between, meaning that both sides are right about some cases,
> but
> >> > >> >> wrong
> >> > >> >> in others.  Not at all surprising.
> >> > >> >>
> >> > >> >>        Perhaps the strongest case for a large number of oceanic
> >> > >> >> dispersals
> >> > >> >> is probably from the African mainland to Madagascar.  And the
> case
> >> > for
> >> > >> >> numerous oceanic dispersals between the African mainland and
> South
> >> > >> >> America
> >> > >> >> (when they were closer together) is more controversial, but
> there
> >> is
> >> > >> >> apparently evidence that some of those dispersals were along
> island
> >> > >> >> chains
> >> > >> >> that no longer exist.  Whether such islands existed or not, the
> >> > debate
> >> > >> >> between the two sides seems to be largely centered on molecular
> >> > >> >> estimates
> >> > >> >> of divergence (about which Grehan seems to repeatedly complain
> ad
> >> > >> >> nauseum).  Therefore, my increasing reluctance to respond to his
> >> > >> >> continued
> >> > >> >> "baiting".  If he wants evidence, there is lots of evidence in
> the
> >> > >> >> literature from many authors (many who seem to be somewhat more
> >> > >> >> objective
> >> > >> >> than Alan de Queiroz).
> >> > >> >>
> >> > >> >>        The case for oceanic dispersal from Australia (including
> >> > >> >> Tasmania)
> >> > >> >> to New Zealand is admittedly even more controversial.  That
> >> > controversy
> >> > >> >> not
> >> > >> >> only involves molecular estimates of divergence, but also
> whether
> >> or
> >> > >> >> not
> >> > >> >> New Zealand was completely submerged at some time in the mid
> >> > Cenozoic.
> >> > >> >> Therefore, I am  playing devil's advocate in suggesting how one
> or
> >> > two
> >> > >> >> species of Nothofagus could have rafted from Tasmania to New
> >> Zealand
> >> > in
> >> > >> >> the
> >> > >> >> middle of the Cenozoic.  Maybe they did and maybe they didn't,
> but
> >> > both
> >> > >> >> possibilities should be kept in mind.  Given the long-standing
> >> debate
> >> > >> >> between Alan de Queiroz and Michael Heads, I find the Nothofagus
> >> case
> >> > >> >> the
> >> > >> >> most challenging (even though some earlier Nothofagus dispersals
> >> seem
> >> > >> >> likely to have been due to vicariance over land in Gondwana).
> >> > >> >> Nothofagus
> >> > >> >> distribution could be due to a combination of both vicariance
> and
> >> > some
> >> > >> >> cases of more recent oceanic dispersal.
> >> > >> >>
> >> > >> >>                                    ------------------Ken
> >> > >> >>
> >> > >> >>
> >> > _______________________________________________
> >> > Taxacom Mailing List
> >> > Send Taxacom mailing list submissions to: Taxacom at mailman.nhm.ku.edu
> >> >
> >> > http://mailman.nhm.ku.edu/cgi-bin/mailman/listinfo/taxacom
> >> > The Taxacom Archive back to 1992 may be searched at:
> >> > http://taxacom.markmail.org
> >> > To subscribe or unsubscribe via the Web, visit:
> >> > http://mailman.nhm.ku.edu/cgi-bin/mailman/listinfo/taxacom
> >> > You can reach the person managing the list at:
> >> > taxacom-owner at mailman.nhm.ku.edu
> >> >
> >> > Nurturing Nuance while Assaulting Ambiguity for 31 Some Years,
> 1987-2018.
> >> >
> >> _______________________________________________
> >> Taxacom Mailing List
> >> Send Taxacom mailing list submissions to: Taxacom at mailman.nhm.ku.edu
> >>
> >> http://mailman.nhm.ku.edu/cgi-bin/mailman/listinfo/taxacom
> >> The Taxacom Archive back to 1992 may be searched at:
> >> http://taxacom.markmail.org
> >> To subscribe or unsubscribe via the Web, visit:
> >> http://mailman.nhm.ku.edu/cgi-bin/mailman/listinfo/taxacom
> >> You can reach the person managing the list at:
> >> taxacom-owner at mailman.nhm.ku.edu
> >>
> >> Nurturing Nuance while Assaulting Ambiguity for 31 Some Years,
> 1987-2018.
> >>
> > _______________________________________________
> > Taxacom Mailing List
> > Send Taxacom mailing list submissions to: Taxacom at mailman.nhm.ku.edu
> >
> > http://mailman.nhm.ku.edu/cgi-bin/mailman/listinfo/taxacom
> > The Taxacom Archive back to 1992 may be searched at:
> http://taxacom.markmail.org
> > To subscribe or unsubscribe via the Web, visit:
> http://mailman.nhm.ku.edu/cgi-bin/mailman/listinfo/taxacom
> > You can reach the person managing the list at:
> taxacom-owner at mailman.nhm.ku.edu
> >
> > Nurturing Nuance while Assaulting Ambiguity for 31 Some Years, 1987-2018.
> _______________________________________________
> Taxacom Mailing List
> Send Taxacom mailing list submissions to: Taxacom at mailman.nhm.ku.edu
>
> http://mailman.nhm.ku.edu/cgi-bin/mailman/listinfo/taxacom
> The Taxacom Archive back to 1992 may be searched at:
> http://taxacom.markmail.org
> To subscribe or unsubscribe via the Web, visit:
> http://mailman.nhm.ku.edu/cgi-bin/mailman/listinfo/taxacom
> You can reach the person managing the list at:
> taxacom-owner at mailman.nhm.ku.edu
>
> Nurturing Nuance while Assaulting Ambiguity for 31 Some Years, 1987-2018.
>