The long distance swim is not that irrational pigmy hippos occurred in Cyprus
(even a distinct genus), Malta and Sicily. Madagaskar and Afrika can well be
connected with a land bridge some say according to some clues. For arrival of
megafauna via swimming abilities a distance of 30 km is enough, according to
literature. Since it is semi aquatic swimming to that island is possible, in
combination with the debris drift. Question here must be why hippos and not
other similar animals like crocodiles.
Note: Crocodiles has reached reportedly only once -recently found i think- to
Europe in Pliocene events
Alıntı yapılıyor [log in to unmask]:
> Paleontologists have identified three different species of dwarf
> Hippopotamuses in the fossil record of Madagascar, a large island the
> size of California hundreds of miles off the coast of Africa. Now
> Madagascar split off from Africa (they were both part of Gondwanaland)
> during the Jurassic era, when dinosaurs ruled and mammals were yet to
> arrive on the scene). So how did the original African hippo (pregnant
> female) or hippos (fertile pair) make it all the way to Madagascar? It
> hardly seems likely they swam there. Some propose island hoping, but it
> is inconsistent with the known geology, and would be a stretch anyway
> considering hippos unproven long distance swimming capabilities. The
> accepted theory is that they rafted there, presumably as the result of
> being carried there with huge amounts of debris after a big storm.
>
> At first consideration this seems preposterous, but a lot can happen in
> a hundred million years. As Lamarck pointed out, one must never forget
> the effect of very long periods of time. It makes nearly anything
> possible.
>
> OK, admittedly I recited the above from memory but I think the essence
> is correct. The point is that we have to abandon our reference frame
> when considering what is possible in evolutionary terms.
>
> Scott
>
>
> ----- Original Message ----
> From: Martin H. Eastburn <[log in to unmask]>
> To: [log in to unmask]
> Sent: Wednesday, October 17, 2007 2:23:55 PM
> Subject: Re: [CONCH-L] Can introductions be assimilated to range e
> xtensions?
>
> Consider the tornado we have from time to time.
> When as a lad of 3 or 4 I lived in Susun bay in the delta area NE of
> San Francisco.
>
> It was a small town built on a spit of land surrounded by slews and
> rivers.
>
> A tornado walked through the slew and deposited tadpoles and fish
> all over town.
>
> A simple example of a vacuum to a young boy who thought it was neat
> until the hot sun came out. It took time and more rain storms
> to clear the houses and bushes. Birds helped but only so much could be
> done. That part of my memory for the most part is gone. Must have
> been bad.
>
>
> As improbable for transportation by a hurricane - I had mentioned the
> rip and tear mode for attached egg piles or such. Once in the water
> floating they are at the mercy of the water current.
>
> The Hurricanes in the Gulf have been known to trap birds, fish and
> boats.
> But when the water is like a mud bath of eggs during the season - times
> when we
> refuse to go snorkeling due to visibility issues that can be drawn
> from area to area.
>
> While on island we went through a number of large storms. One storm
> Zelda did a real number on the islands. They always ripped reef off
> the protective ring we lived upon. The heavy parts fell thousands of
> feet deep while the light stuff - sea weed and what not was flung
> to the far winds. Traversing thousands of miles is sketchy, but
> from chain to chain or island to island it seems logical.
>
> And yes trees of all shapes sizes float in open ocean as well as
> some large beautiful masts. One can in that was so large (mast)
> and it was full of worm holes - hum - open ocean but they attacked.
> Maybe it washed ashore and blown out to sea again. - it was cut
> up into slabs of wood and dried. Some beautiful wood that required
> carbide tools was generated.
>
> Martin
>
> Allen Aigen wrote:
> > As Martin noted, rare events, over a long enough period of time, come
> > to be expected events. Shallow water gastropod species with crawl
> > away larva cannot crawl from island to island in the Caribbean where
> > the water depth separating the islands is too great. Even lowering
> > the water a few hundred feet due to glaciation would not be sufficient
> > in many cases to allow simple transport. Although it can be
> > considered to be very improbable for eggs or small specimens to be
> > transported during a hurricane (possibly attached to a vegetation
> > mat), over enough time they will be, and apparently this has happened
> > for many shallow water species. Could this also have been the
> > deliberate or inadvertant work of people? In some cases, possibly
> > yes, in other cases they were spread long before people arrived.
> >
> > Allen Aigen
> > [log in to unmask]
> >
> > -- \"Martin H. Eastburn\" <[log in to unmask]> wrote:
> > Thinking on this - just a quick note - how about transportation and
> > range extension:
> >
> > Egg clusters floating - even those attached - ripped up by a storm.
> > Then the ocean stream tugs it from the south pacific up the Japanese
> > current and drops some off here and there.
> >
> > Typhoons, hurricanes help rip and transport as well.
> >
> > While on Kwajalein - we had both bird and airplane caught in winds
> > and came in for landings.
> > And some of the \'crane\' like \'stork\' water walking birds might
> > transport eggs on their feet/legs. Boats in lakes do that as well.
> >
> > Naturally is nature way, not man doing it on purpose.
> >
> > Martin
> >
> > Pete Krull wrote:
> > > The term \"range extension\" to me means that someone has found a
> > naturally
> > > occurring, long standing population outside of the area where we
> already
> > > knew they lived. The \"range\" of many species is greater than what we
> > know at
> > > any point in time only because we haven\'t discovered the true limits
> > to that
> > > range.
> > >
> > > An \"introduction\", by definition, is not a range extension. Pete K.
> > >
>
> --
> Martin H. Eastburn
> @ home at Lions\' Lair with our computer lionslair at consolidated dot
> net
> TSRA, Life; NRA LOH & Patron Member, Golden Eagle, Patriot\'s Medal.
> NRA Second Amendment Task Force Charter Founder
> IHMSA and NRA Metallic Silhouette maker & member.
> http://lufkinced.com/
>
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