Proposal (132) to South American Classification Committee
Merge families Dendrocolaptidae and Furnariidae
Effect on SACC: This would combine two families into one.
Background: Controversy over whether the woodcreepers and ovenbirds should both be ranked at the family level or treated as subfamilies of the same family go almost 100 years. See brief summary under Dendrocolaptidae at the SACC site, or see Remsen (2003) or Marantz et al. (2003). The controversy has two components: a trivial one on whether each group "deserves" family or subfamily rank, and an important one on whether the two groups are reciprocally monophyletic.
New data: Irestedt et al.'s (2002) DNA sequence data indicated that Furnariidae was paraphyletic with respect to the Dendrocolaptidae because Sclerurus was basal to Dendrocolaptidae + rest of Furnariidae. Chesser (2004) analyzed both nuclear and mitochondrial DNA and had much greater taxon-sampling than Irestedt et al. (2002); he found strong support for the above relationship (e.g., 99% bootstrap value) as well as for Geositta also lying outside Dendrocolaptidae + rest of Furnariidae (and Geositta and Sclerurus as sisters). Of interest is that Ames (1971) long ago noted that Geositta did not have the syringeal structure that defined the rest of the Furnariidae. Geositta and Sclerurus each have unique minor phenotypic traits that distinguish them from other ovenbirds (Remsen 2003).
Analysis: Two independent genetic data sets strongly indicate that the Furnariidae is a paraphyletic taxon as currently constituted, thus confirming suspicions that date back to at least Ihering (1915) and consistent with morphological data (e.g., Ames 1971, Feduccia 1973). Therefore, to maintain the two families as monophyletic taxa, as in our current list, is not defensible with any data of which I am aware.
One solution would be to create yet a third family-level taxon for Geositta + Sclerurus, but with only one data set to support the monophyly of that grouping, I would be highly reluctant to concoct a novel family-level taxon (especially given the rather disturbing biogeographic anomaly that that sister relationship would represent).
The other solution is to simply revert to earlier treatments that recognize only a single family, Furnariidae and to also abandon subfamily ranks for woodcreepers and ovenbirds.
Recommendation: I vote YES on this because the combination of recent genetic and historical evidence makes untenable the ranking these two groups as separate taxa at any level.
If this proposal passes, I may do another on linear sequence with respect to Geositta and Sclerurus. For now, however, the effect on our list would be to simply place all Dendrocolaptidae at the END of the Furnariidae.
AMES, P. L. 1971. The morphology of the syrinx in passerine birds. Bulletin Peabody Museum Natural History 37: 1-194.
CHESSER, R. T. 2004. Molecular systematics of New World suboscine birds. Molecular Phylogenetics and Evolution 32: 11-24.
FEDUCCIA, A. 1973. Evolutionary trends in the Neotropical ovenbirds and woodhewers. Ornithol. Monogr. 13.
IRESTEDT, M., J. FJELDSĀ, U. S. JOHANSSON, AND P. G. P. ERICSON. 2002. Systematic relationships and biogeography of the tracheophone suboscines (Aves : Passeriformes). Molecular Phylogenetics & Evolution 23: 499-512.
MARANTZ, C. A., A. ALEIXO, L. R. BEVIER, AND M. A. PATTEN. 2003. Family Dendrocolaptidae (woodcreepers). Pp. 358-447 in "Handbook of the Birds of the World, Vol. 8. Broadbills to tapaculos." (J. del Hoyo et al., eds.). Lynx Edicions, Barcelona.
REMSEN, J. V., JR. 2003. Family Furnariidae (ovenbirds). Pp. 162-357 in "Handbook of the Birds of the World, Vol. 8. Broadbills to tapaculos." (J. del Hoyo et al., eds.). Lynx Edicions, Barcelona.
Van Remsen, September 2004
Comments from Stiles: "YES. Ever since Feduccia's study I have felt comfortable with woodcreepers as a subfamily of Furnariidae (though less so if all subfamilies are abolished, though this might be a necessary result of the Sclerurus-Geositta connection). Actually, the latter might not be so terribly illogical as an old subfamily of very terrestrial furnariids that initially got split by the Andes rising, with the Pacific guys adapting to very dry habitats and the eastern bunch spreading into humid forest)."
Comments from Robbins: "YES, as the molecular data clearly support this treatment."
Comments from Nores: "YES; a pesar de que sentimentalmente me resulta poco agradable eliminar la familia Dendrocolaptidae, el hecho de que dos diferentes estudios genéticos llegan a la misma conclusión resulta definitivo. De todos modos, sigo pensando que en morfología y comportamiento son bastante diferentes como para pertenecer a diferentes familias."
Comments from Silva: "YES. I think this is the best solution."
Comments from Zimmer: "I vote "YES" for all of the reasons stated by Van."
Comments from Jaramillo: "YES _ However, I am uncomfortable doing away with the subfamilies. Is it not reasonable to propose a new subfamily for Sclerurus and Geositta? Was Upucerthia sampled in the Chesser paper? I have a hard time believing that Geositta and Upucerthia are not in the same group.”
Additional comment from Remsen: “Alvaro – yes Upucerthia sampled.”