Pacific flightless rails (2 Viewers)

[Richard Klim]

Kirchman (in press). Speciation of flightless rails on islands: a DNA-based phylogeny of the typical rails of the Pacific. Auk. [abstract]

 

[Peter Kovalik]

Kirchman (in press). Speciation of flightless rails on islands: a DNA-based phylogeny of the typical rails of the Pacific. Auk. [abstract]

TiF update January 8 2012
http://jboyd.net/Taxo/changes.html

 

[Melanie]

Is someone here who has this paper? It is somewhat strange to see that Aramidopsis, Eulabeornis, Habroptila, Lewinia, and Nesoclopeus are no more distinct from Gallirallus.

 

[Capreolus]

Is someone here who has this paper? It is somewhat strange to see that Aramidopsis, Eulabeornis, Habroptila, Lewinia, and Nesoclopeus are no more distinct from Gallirallus.

Why does it seem strange, Melanie? Members of the 5 genera you named are all similar to Gallirallus rails, and 3 of the genera are monotypic. Several of the present members of Gallirallus were formerly classified in genera that are now obsolete, including the Weka (Ocydromus), New Caledonian Rail and Lord Howe Rail (Tricholimnas), and Buff-banded Rail, Guam Rail, and Wake Island Rail (Hypotaenidia).

All three of the extinct Chatham Islands rails were derived from a Gallirallus ancestor, but the smallest and largest were and still are placed in their own monotypic genera, Cabalus and Diaphorapteryx. It makes no sense.

Rick

 

[Peter Kovalik]

Kirchman (in press). Speciation of flightless rails on islands: a DNA-based phylogeny of the typical rails of the Pacific. Auk. [abstract]

The previous related Kirchman's paper:
Jeremy J. Kirchman, 2009. Genetic tests of rapid parallel speciation of flightless birds from an extant volant ancestor. Biological Journal of the Linnean Society, Volume 96, Issue 3, pages 601–616.
Abstract

 

[dnsallen]

Why does it seem strange, Melanie? Members of the 5 genera you named are all similar to Gallirallus rails, and 3 of the genera are monotypic. Several of the present members of Gallirallus were formerly classified in genera that are now obsolete, including the Weka (Ocydromus), New Caledonian Rail and Lord Howe Rail (Tricholimnas), and Buff-banded Rail, Guam Rail, and Wake Island Rail (Hypotaenidia).

All three of the extinct Chatham Islands rails were derived from a Gallirallus ancestor, but the smallest and largest were and still are placed in their own monotypic genera, Cabalus and Diaphorapteryx. It makes no sense.

Rick

Surely it is a question of HOW similar. Habroptila skins look very different from Gallirallus. To what extent should we be distrusting morphological differences in favour of partial DNA analysis?
Des

 

[Capreolus]

Surely it is a question of HOW similar. Habroptila skins look very different from Gallirallus. To what extent should we be distrusting morphological differences in favour of partial DNA analysis?
Des

Good question, Des, and one I've thought about for a long time to no certain conclusion, and not just concerning the generic limits of Gallirallus, but other genera as well. The point is, given the great disparity in size, color, and bill morphology within Gallirallus (compare the Weka with the extinct Tahiti Rail, G. pacificus), it's plausible that Habroptila and the other genera are part of the Gallirallus radiation.

 

[Melanie]

The article is now available at Bioone.

It suggests the following new combinations

Gallirallus castaneoventris (Gould) Kirchman comb. nov. (formerly Eulabeornis castaneoventris)
Gallirallus wallacii (Gray) Kirchman comb. nov. (formerly Habroptila wallacii)
Gallirallus plateni (Sharpe) Kirchman comb. nov. (formerly Aramidopsis plateni)

I am curious whether and when the IOC and BLI will recognize these changes.

 

[l_raty]

The article is now available at Bioone.

It is also the "Editor's Choice" paper of the last Auk issue:
http://www.aou.org/
...and as such is temporarily freely accessible at JStor:
http://www.jstor.org/stoken/ucaltoken/Q6SjQai4u5Eji6STNIyS/full

 

[l_raty]

In barcode-based ID trees from BOLD, "Rallus" pectoralis pops up as the sister group of the corncrake, these being sister to Gallirallus (australis, okinawae, "Nesoclopeus" woodfordi, owstoni, philippensis; see attachment for an example).
If true, this would make the proposed arrangement untenable: Gallirallus could not be extended beyond the limits of group "3" in Fig. 3 of Kirchman's paper; making it broader would make it include the type species of Crex, and Crex has priority...

(Of course it could also not be true. I don't think that this can be further tested with publicly available data.)

 

[l_raty]

I don't think that this can be further tested with publicly available data.

No, apologies: it can be tested to some extent, actually--not with pectoralis, because the sequence that is in the BOLD database is not accessible; but I hadn't noticed two COI sequences of Gallirallus striatus, the sister species of pectoralis in Kirchman's analysis, that are now in GenBank but not in BOLD.
The test is not really conclusive, though--Crex, striatus, and the other Gallirallus clearly cluster together, but they are about equidistant, and I cannot say which one diverged from the others first.

 

[Richard Klim]

TiF

John Boyd (TiF):
www.jboyd.net/Taxo/changes.html [30 Sep 2012]
www.jboyd.net/Taxo/List6.html#rallidae

 

[Peter Kovalik]

Weka

Trewick, S. A., Pilkington, S., Shepherd, L. D., Gibb, G. C. and Morgan-Richards, M. (), Closing the gap: avian lineage splits at a young, narrow seaway imply a protracted history of mixed population response. Mol Ecol. Accepted Author Manuscript.

Abstract:

The evolutionary significance of spatial habitat gaps has been well recognised since Alfred Russel Wallace compared the faunas of Bali and Lombok. Gaps between islands influence population structuring of some species, and flightless birds are expected to show strong partitioning even where habitat gaps are narrow. We examined the population structure of the most numerous living flightless land bird in New Zealand and the world, Weka (Gallirallus australis). We surveyed Weka and their feather lice in native and introduced populations using genetic data gathered from DNA sequences of mitochondrial genes and nuclear β-fibrinogen and five microsatellite loci. We found low genetic diversity among extant Weka population samples. Two genetic clusters were evident in the mtDNA from Weka and their lice, but partitioning at nuclear loci was less abrupt. Many formerly recognized subspecies/species were not supported; instead we infer one subspecies for each of the two main New Zealand islands. Although currently range restricted, North Island Weka have higher mtDNA diversity than the more wide-ranging southern Weka. Mismatch and neutrality statistics indicate North Island Weka experienced rapid and recent population reduction while South Island Weka display the signature of recent expansion. Similar haplotype data from a widespread flying relative of Weka, and other New Zealand birds revealed instances of North Island - South Island partitioning associated with a narrow habitat gap (Cook Strait). However, contrasting patterns indicate priority effects and other ecological factors have a strong influence on spatial exchange at this scale.