Dear Barb,
The difference in song between eastern and western Nearctic Winter Wrens is
interesting given that these populations are distinct from a phylogenetic
point of view. A recent molecular paper by the Zink lab indicates that the
split between eastern and western Nearctic Winter Wrens is 1.6 million year=
s
old.
Best wishes,
George Sangster
The Netherlands
Drovetski, SV, Zink, RM, Rohwer, S, Fadeev, IV, Nesterov,
EV, Karagodin, I, Koblik, EA, Red'kin, YA 2004. Complex
biogeographic history of a Holarctic passerine. Proc. R.
Soc. London B 271: 545 - 551.
ABSTRACT
Our analysis of the ND2 sequences revealed six clades within
winter wrens (Troglodytes troglodytes). These clades
corresponded to six geographical regions: western Nearctic,
eastern Nearctic, eastern Asia, Nepal, Caucasus and Europe,
and differed by 3-8.8% of sequence divergence. Differences
among regions explained 96% of the sequence variation in
winter wren. Differences among individuals within localities
explained 3% of the sequence variation, and differences
among localities within regions explained 1%. Grouping
sequences into subspecies instead of localities did not
change these proportions. Proliferation of the six clades
coincided with Early and Middle Pleistocene glaciations. The
distribution of winter wren clades can be explained by a
series of five consecutive vicariant events. Western
Nearctic wrens diverged from the Holarctic ancestor 1.6 Myr
before the present time (MYBP). Eastern Nearctic and
Palaearctic wrens diverged 1 MYBP. Eastern and western
Palaearctic birds diverged 0.83 MYBP. Nepalese and east
Asian wrens diverged 0.67 MYBP, and Caucasian birds diverged
from European wrens 0.54 MYBP. The winter wren has a much
greater degree of inter- and intracontinental
differentiation than the three other Holarctic birds studied
to date--dunlin (Calidris alpina), common raven (Corvus
corax) and three-toed woodpecker (Picoides trydactylus)--and
represents an example of cryptic speciation that has been
overlooked.
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