Geography Reference
In-Depth Information
Swedish entomologist Lars Brundin (1907-1993) published in 1966
Transantarctic Relationships and Their Significance as Evidenced by
Midges
. In this monograph he devoted a section to explaining Hennig's
phylogenetic biogeographic methods and discussed the relevance of the
sister group in the reconstruction of the biogeographic history of a taxon.
Brundin (1966) was one of the first authors to accept the theory of contin-
ental drift and used it to support transantarctic disjunctions of the Chironom-
idae analyzed. Brundin's impact on biogeography has been arguably great-
er than Hennig's because of the clear exposition of his ideas and because
he developed the method and convinced other authors of the relevance of
phylogenetics in biogeography (Funk 2004). He saw the key to a deeper
understanding of evolution through biogeography rather than paleontology
(Williams and Ebach 2004).
Brundin (1981) characterized phylogenetic biogeography as the study of
the history of monophyletic groups of nature's hierarchy in space and time.
Methodologically, he stated that this approach studies the causal connec-
tions between phylogenesis (development of hierarchy in space and time),
allopatry (vicariance), sympatry (dispersal), and paleogeographic events. In
order to exemplify this approach, one may examine Brundin's (1981) ana-
lysis of one of the taxa analyzed in 1966, the tribe Podonomini. Its area
hibit a three-area pattern including Australia, Patagonia, and New Zeal-
and, whereas
Rheochlus
and
Podonomopsis
have developed a two-area
pattern comprising Australia and Patagonia. Together these genera are in-
volved in multiple sympatric vicariance between Patagonia and Australia,
where the Australian species of each genus stands out as a young and
moreapomorphicoffshootofanolderPatagoniangroup.Onthebasisofthis
cladogram, Brundin concluded that the occurrence in Australia of species of
Podonomus, Podochlus, Rheochlus,
and
Podonomopsis
is due to dispersal
from South America or East Antarctica of the common ancestor with their
sisterspeciesinPatagonia.Hepostulatedthatdispersaloccurredbeforethe
break between East Antarctica and Australia between the Paleocene and
Eocene. Within the apomorphic genus
Podonomopsis,
however, there are
twocasesoftwo-areavicariance.TheNewZealandtaxadifferfromtheAus-
tralian ones by their older relative age.
Rheochlus
and
Podonomopsis
are
not represented in New Zealand, and if they ever occurred in West Antarc-
tica, they were probably too young to reach New Zealand before its separa-
tion from West Antarctica in the upper Cretaceous. They might have origin-
