Timing, exotic terranes, angiosperm diversification, and panbiogeography

), I commented upon the methodology of panbiogeography. These comments were later criticized by Grehan (1994). In writing a reply to Grehan, I found that it was necessary to construct a wider analysis and review of panbiogeography, so that my original comments, as well as Grehan's criticisms, can be seen in the context of Croizat's original views as well as in that of the more recent elaboration of his theory by Grehan and others.

Section: Prologuementioning

confidence: 82%

Section: Prologuementioning

confidence: 99%

From generalized tracks to ocean basins—how useful is Panbiogeography?

Cox

1998

“…Craw (1988) similarly attributed the distribution of Hebe elliptica to a vicariance event based on land connections (here including the Chatham Islands, c. 850 km east of New Zealand). Lovis (1989) suggested, in contrast, that:…”

Section: Pattern and Process – A Biogeographical Synthesismentioning

confidence: 98%

Falkland Islands biogeography: converging trajectories in the South Atlantic Ocean

McDowall¹

2004

Aim This paper describes the biogeographical setting of the Falkland Islands, in the context of the relationships of the islands’ biota to other sub‐Antarctic/cold temperate lands. Location The analysis focuses primarily on the Falklands biota, and explores its relationships to those of Patagonian South America and South Africa, other southern lands and the islands of the sub‐Antarctic Pacific, Indian and Atlantic Oceans. Methods The study derives largely from literature sources on the biota and geological history of the Falkland Islands. Results The animals and plants known from the Falkland Islands exhibit strong affinities with those of Patagonian South America, and especially Tierra del Fuego; additional affinities are with various remote islands of the sub‐Antarctic, as well as New Zealand and to a lesser extent Australia; often these are shared with Patagonia. While the biotic affinities might be interpreted, by some, as indicating a former Gondwanan/South American geological connection of the Falklands, geological evidence points to the Falklands formerly having a land connection to south‐eastern South Africa. Only faint hints of a South African biotic connection remain. The historical biotic and geological connections of the Falklands thus conflict. Moreover, the Falklands biota is so strongly Patagonian that derivation of that biota is best seen as resulting from dispersal, much of it probably recent. This dispersal biota appears to have replaced, and perhaps displaced, the South African biota present on the islands as they detached from South Africa and drifted across the south Atlantic Ocean, as it opened up as South America and Africa drifted apart.

“…140 Ma). Furthermore, the relevant rock strata were probably entirely marine and unlikely to have been capable of transporting terrestrial biota (Cooper, 1989; Lovis, 1989). A more orthodox vicariance hypothesis can be developed from geological evidence that indicates that New Zealand and the Chathams area have not been in direct terrestrial contact since the Pacific and Australasian tectonic plates separated at least 70 Ma (Campbell et al.…”

Section: Introductionmentioning

confidence: 99%

Molecular evidence for dispersal rather than vicariance as the origin of flightless insect species on the Chatham Islands, New Zealand

Trewick

2000

127

AimThe aim was to use mitochondrial DNA sequence data to test between vicariance and oversea dispersal explanations for the origin of the Chatham Islands biota.Location New Zealand and the Chatham Islands, separated by c . 800 km in the south-west Pacific Ocean.Methods DNA sequences from the mitochondrial gene cytochrome oxidase I (COI) were obtained from four genera of relatively large and flightless insects (Coleoptera-Geodorcus , Mecodema ; Orthoptera-Talitropsis ; Blattoidea -Celatoblatta ). These were used to test alternative hypotheses for the origin of the Chatham taxa.Results Phylogenetic analysis revealed the Chatham taxa in each genus to be monophyletic. Genetic distances exhibited by these genera, between taxa found on the Chatham Islands and mainland New Zealand were relatively low (11.2, 2.8, 3.0 and 4.9%, respectively). Main conclusionsEven allowing for variation in molecular evolutionary rates, these genetic distances indicate phylogenetic separation of New Zealand and Chatham insect lineages in the Pliocene (2-6 Ma). Such dates are more than one order of magnitude too recent to be explained by vicariant (tectonic) processes. Oversea dispersal from New Zealand to the Chatham Islands is implicated and this conclusion is in keeping with the taxonomy of the endemic avifauna, flora and fossil molluscan fauna.