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[Taxacom] Killifish biogeography

John Grehan calabar.john at gmail.com
Sat Apr 5 12:19:19 CDT 2014 

Briggs asserts that the Cyprindondiformes are part of the Antherinomorpha
for which the oldest fossil dates are from the early to mid-Tertiary and
alognth older fossils are not precluded, their appearance becomes "less
probable" as time goes by. No explanation of what this means scientifically.



Then Briggs makes a huge leap in logic by saying "If, as the fossil
record *seems
to indicate*, the aplocheiloid fishes are too young to have been carried
about on tectonic plates, how did they achieve their cir-cumglobal range?"



This reads as a slight of hand, by claiming that the fossil records "seems
to indicate" that the fishes are too young and therefore they are to young,
and having established that claim (not evidence) they must have achieved
their range without being carried on tectonic plates. The rest of his
argument is the invention of centers of origin and dispersal routes. Pure
fiction.

JohnGrehan


On Fri, Apr 4, 2014 at 8:05 PM, Ken Kinman <kinman at hotmail.com> wrote:

> Hi Michael,
>         Oh yes, there was definitely a response by dispersalist Briggs
> (Briggs J. C., 2003.  Fishes and birds: Gondwana life raft. reconsidered.
> Syst. Biol.;52:548-553).  And Sparks and Smith (2005) then responded to
> Briggs (about the killifish and cichlids).  It is a very interesting
> debate, and I am not yet fully convinced by either side on the killifish
> debate.  I was at first inclined to accept vicariance as the major factor
> in killifish biogeography, but now I am back on the fence and looking more
> carefully at dispersal (even across the ocean barrier between Madagascar
> and Africa).
>                                 -----------------Ken Kinman
> Date: Sat, 5 Apr 2014 10:08:07 +1300
> Subject: Re: [Taxacom] Panbiogeography
> From: m.j.heads at gmail.com
> To: kinman at hotmail.com; taxacom at mailman.nhm.ku.edu
>
> Hi Ken, I didn't mean to imply that there was a debate about this group.
> Murphy & Collier (1997) accepted vicariance, but I don't know if there have
> been any responses to this from dispersalists.
>  Michael
>
> On Fri, Apr 4, 2014 at 1:30 PM, Ken Kinman <kinman at hotmail.com> wrote:
>
>
>
>
> Hi Michael,
>          I don't know much about the debate concerning killifish
> biogeography, but assume (since you brought it up) that it must still be
> controversial (as with the cichlid fishes we discussed previously).  I can
> certainly see how the killifishes could be one of the few taxa which
> survived on Madagascar during the K-T extinction which killed off so many
> other vertebrates there.  Especially since some killifish can enter
> diapause during periods of drought and/or starvation.
>
>         Are you asking my opinion whether I side in this particular case
> with the dispersalists or those advocating vicariance?  If so, I would have
> to look at the dispersalist arguments on the other side of the debate.  Are
> there any recent papers still suggesting dispersal played a major role in
> the broad (worldwide) biogeography of killifish?   Sounds like an
> interesting debate.
>
>                            --------------------------Ken
>
> --------------------------------------------------------------------------------------------------------
>
> > Date: Fri, 4 Apr 2014 10:39:23 +1300
> > From: m.j.heads at gmail.com
> > To: taxacom at mailman.nhm.ku.edu
>
> > Subject: Re: [Taxacom] Panbiogeography
> >
> > Hi Ken,
> >
> > The aplocheiloid killifish illustrate a standard pattern, with two main
> > clades (Fig. 2-3 in my 2012 book). One is in America, and (another
>
> > subclade) mainland Africa. It's not in Madagascar, and you might
> > assume that this was the result of extinction there. But the other main
> > clade is in Madagascar and the Seychelles, and also (another
>
> > subclade) from India to Java.
> >
> > You could explain the pattern by chance dispersal from anywhere within
> the
> > whole range, e.g. Guatemala or Gabon or Goa. Chance dispersal is not
> > related to any other factor, and so this wouldn't make any particular
>
> > predictions.
> >
> > As an alternative, both groups could have been everywhere to begin with,
> > and you could explain the pattern by the chance extinction of the first
> > group from Madagascar - Java, and the chance extinction of the second
> group
>
> > from America and Africa. This would predict fossils in the area of
> absence,
> > but none have ever been found. It's also difficult to imagine why one
> group
> > would go extinct in an area that is exactly allopatric with the area
> where
>
> > the other group went extinct. This explanation also leaves the original
> > differentiation of the groups unaccounted for.
> >
> > Or you could explain the pattern by simple vicariance, with the first
> break
>
> > located between Africa and Madagascar, at the Mozambique Channel. This
> > would make the general predictions that other groups would show similar
> > patterns, and that there would be a simple correlation between the
> pattern
>
> > and tectonics, climate or some other environmental factor. Note that the
> > first break, between Africa and Madagascar, comes before the secondary
> > breaks (between America and Africa, and between Madagascar-Seychelles,
> and
>
> > India - Java). This is congruent with the continental breakup sequence.
> >
> > Michael
> >
> >
> >
> > On Thu, Apr 3, 2014 at 11:17 AM, Ken Kinman <kinman at hotmail.com> wrote:
>
> >
> > > Hi Juerg,
> > >        Well, certainly not a nude rock.  However, as I explained in an
> > > earlier posting, the end-Cretaceous extinction wiped out a lot of taxa
> > > (most vertebrates and probably all mammals).  This left it with a lot
> of
>
> > > empty niches which new mammals and birds, etc. would fill during the
> > > early-to-mid Tertiary.
> > >         But I suppose John would deny that the end-Cretaceous
> extinction
> > > was that bad in Madagascar.  I am giving up arguing with him about
>
> > > Madagascar, because he just repeats the same old fallback positions,
> and
> > > now claiming that there is no "analytical evidence" for dispersal to
> > > Madagascar.  It might not be strictly analytical evidence according his
>
> > > definition of analytical, but there is plenty of evidence.  He simply
> > > refuses to accept any of it.   I should have given up trying to reason
> with
> > > him a long time ago.
> > >                       -------------------Ken Kinman
>
> > >
> > >
> -----------------------------------------------------------------------------------------------------
> > > > From: demarmjc at hotmail.com
>
> > > > To: taxacom at mailman.nhm.ku.edu
> > > > Date: Wed, 2 Apr 2014 17:00:29 -0400
> > > > Subject: Re: [Taxacom] Panbiogeography
>
> > > >
> > > > Seeing the comments by our dispersalist friends, I wonder then,
> whether
> > > Madagascar was empty, a piece of nude rock, before the "great
> migration"
> > > out of Africa?
>
> > > > Juerg De Marmels
> > > >
>
>
>
>
>
>
> --
> Dunedin, New Zealand.  My recent books: Molecular panbiogeography of the
> tropics. 2012. University of California Press, Berkeley.
> www.ucpress.edu/book.php?isbn=9780520271968
>  Biogeography of Australasia:  A molecular analysis. 2014. Cambridge
> University Press, Cambridge. www.cambridge.org/9781107041028
>
>
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