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Axiomatic Panbiogeography

offers an application of incidence geometry to historical biogeography by defining collection localities as points, tracks as lines and generalized tracks as planes.
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Geology



A relationship between geology and geographic distributions has been a focus of the work or Michale Heads.  Some have questioned his supposition of a Pacific connection through the geological past into the present distribution of living things.

[Taxacom] "Masteria mystery" solved?


Hi Ken,
 
I'm not quite sure that I follow your line of reasoning. Are you suggesting a center of origin for Masteria in Antarctica? Platnick (AMNH spider website) does not accept that the Indian species of Ischnothele belongs in the genus (America/India would be a very unusual distribution). He lists Euagrus from Taiwan, Guatemala to USA (standard trans-tropical Pacific) and South Africa (standard trans-Atlantic). The Atlantic opened about the same time that the central Pacific plateaus formed (mid-Cretaceous), which suggests a simple global process for Euagrus. 
 
I don't think Masteria is (currently) an island-hopper - all the species in the Caribbean and all but one in the Pacific are endemic to single archipelagos, compatible with allopatric differentiation in a phase of immobilism. On the other hand, its Cretaceous ancestors may well have been actively dispersing when they colonized the new areas of land provided by the plateaus (possibly from prior islands in the region).  
You suggest Mesozoic vicariance for Masteria and I agree. The large igneous plateaus in the central Pacific have drifted long distances westward (Ontong Java plateau etc.) and eastward (Inca plateau etc.). They included forest (or at least trees) and presumably there were also animals there, so... what happened to them? Could they have been incorporated into America along with the plateaus? This might explain the distinctive distribution of Masteria in America (only in the Caribbean), and in the west Pacific (west only to New Guinea - Philippines).  

Michael

Wellington, New Zealand.

Here is another potential distributional puzzle (1-4 ancestors) that may find confirmation via Heads' suggestions.


Yaminuechelys aff. maior
Where: Neuquén, Argentina (37.5° S, 68.9° W: paleocoordinates 40.4° S, 53.4° W)
When: Anacleto Formation (Neuquén Group), Early/Lower Campanian to Early/Lower Campanian (84.9 - 70.6 Ma)
http://fossilworks.org/?a=collectionSearch&collection_no=132353

Where: Neuquén, Argentina (37.4° S, 69.1° W: paleocoordinates 40.2° S, 53.6° W)
When: Anacleto Formation (Neuquén Group), Early/Lower Campanian to Early/Lower Campanian (84.9 - 70.6 Ma)
http://fossilworks.org/?a=collectionSearch&collection_no=117447


Yaminuechelys (aff. Yaminuechelys) gasparinii
Where: Chubut, Argentina (43.0° S, 67.6° W: paleocoordinates 45.7° S, 53.8° W)
When: Reigitherium mammal zone, Middle Member (La Colonia Formation), Late/Upper Campanian to Late/Upper Campanian (84.9 - 66.0 Ma)
http://fossilworks.org/?a=collectionSearch&collection_no=99438

Where: Chubut, Argentina (43.0° S, 67.6° W: paleocoordinates 45.7° S, 53.7° W)
When: La Colonia Formation, Late/Upper Campanian to Late/Upper Campanian (84.9 - 66.0 Ma)
http://fossilworks.org/?a=collectionSearch&collection_no=166583

Yaminuechelys cf. gasparinii
Where: Río Negro, Argentina (39.1° S, 67.7° W: paleocoordinates 42.1° S, 52.4° W)
When: Anacleto Formation, Early/Lower Campanian to Early/Lower Campanian (84.9 - 70.6 Ma)
http://fossilworks.org/?a=collectionSearch&collection_no=132358

Hydromedusa cf. casamayorensis7, "? Naiadochelys maior" = Yaminuechelys maior2, "Osteopygis sculptus n. sp." = Yaminuechelys maior2
Where: Chubut, Argentina (45.5° S, 67.2° W: paleocoordinates 48.2° S, 56.7° W)
When: Peligran mammal zone, Hansen Member (Salamanca Formation), Middle Paleocene (61.7 - 58.7 Ma)
http://fossilworks.org/?a=collectionSearch&collection_no=95914

"Naiadochelys maior n. sp." = Yaminuechelys maior
Where: Chubut, Argentina (45.3° S, 67.0° W: paleocoordinates 47.8° S, 56.1° W)
When: Hansen Member (Salamanca Formation), Early/Lower Paleocene (66.0 - 61.7 Ma)
http://fossilworks.org/?a=collectionSearch&collection_no=118384

Chelidae indet., Yaminuechelys cf. maior
Where: Rio Negro, Argentina (38.7° S, 67.9° W: paleocoordinates 41.2° S, 56.3° W)
When: Roca Formation (Malargue Group), Danian (66.0 - 61.7 Ma)
http://fossilworks.org/?a=collectionSearch&collection_no=141238

Hydromedusa tectifera
Where: Buenos Aires, Argentina (38.5° S, 61.8° W: paleocoordinates 38.5° S, 61.8° W)
When: Middle Pleistocene (0.8 - 0.1 Ma)
http://fossilworks.org/?a=collectionSearch&taxon_no=37613&max_interval=Quaternary&country=Argentina&is_real_user=1&basic=yes&type=view&match_subgenera=1
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