Plumage Similarities Research Articles

Relationship of Two Bamboo-Specialized Foliage-Gleaners: Automolus dorsalis and Anabazenops fuscus (Furnariidae)

Analyses of several characters indicate that two bamboo specialist fo- liage-gleaners in the Furnariidae - Anabazenops fuscus (White-collared Foliage-gleaner) of southeastern Brazil and Automolus dorsalis (Dusky-cheeked Foliage-gleaner) of west- ern Amazonia - are sister species. The nest site of Automolus dorsalis, above-ground in cavities, indicates that this species does not belong with other species in the genus. Similarities in foraging behavior and vocalizations, as well as similarities in plumage, provide evidence for a close relationship between dorsalis and Anabazenops. Although some morphological similarities are evident, analyses of eight mensural characters were equivocal with regard to a close relationship between these two species. We recommend that A. dorsalis be moved to the genus Anabazenops. Relationships of these two species with other taxa in the subfamily Philydorinae are investigated.

Systematics and Biogeography of Scaled Woodcreepers (Aves: Dendrocolaptidae)

The geographical variation of three qualitative plumage characters and three body measurements of populations of the Scaled Woodcreeper (Lepidocolaptes squamatus), a species whose range is centered in eastern Brazil, is analyzed. Three distinctive populations are recognized (wagleri, squamatus, and falcinellus). Under the biological species concept (BSC), two species are recognized (L. squamatus, including squamatus and wagleri as subspecies; and L. falcinellus). Under either the phylogenetic species concept (PSC) or under the evolutionary species concept (ESC), the three distinctive populations should be regarded as independent species. Based on plumage similarities, we suggest that squamatus and wagleri form a monophyletic group, with falcinellus as its sister-group. Geological changes (tectonism and formation of river courses) are suggested as causal factors that promoted speciation in Scaled Woodcreepers.

Phylogenetic Relationships of the Cinnamon Tyrant, Neopipo cinnamomea, to the Tyrant Flycatchers (Tyrannidae)

A cladistic analysis of 14 binary morphological and nest architecture characters was conducted to investigate the relationship of Neopipo cinnamomea, formerly placed in the manakins (Pipridae), to the Empidonax assemblage of tyrant flycatchers (Tyrannidae; Lanyon 1986, 1988a). The results demonstrate that Neopipo cinnamomea is not a manakin, but a member of the Myiophobus group of tyrannids, which includes Myiophobus, Myiobius (including Terenotriccus erythrurus), Pyrrhomyias, and Hirundinea (Lanyon 1986, 1988a). Detailed illustrations and formal descriptions of the syringeal morphology of Neopipo cinnamomea and related genera are presented. Two alternative, maximally parsimonious phylogenetic hypotheses were identified (length = 20; Consistency Index = 0.70). In both hypotheses, Myiophobus is the sister group to the other five genera, and the monophyly of Myiobius including M. erythrurus is supported. The two alternative hypotheses differ in the hypothesized relationships among Neopipo, Pyrrhomyias and Hirundinea. In the first, Neopipo and Pyrrhomyias constitute a monophyletic group, and Hirundinea is its sister group. In the second, Hirundinea and Pyrrhomyias form a clade with Neopipo as its sister group. These findings strongly confirm that Neopipo is not a member of the Pipridae. It is recommended that Neopipo cinnamomea be referred to as the Cinnamon Tyrant, and that it be included in the Myiophobus group within the Empidonax assemblage of the Tyrannidae. The hypothesis that Neopipo cinnamomea is strikingly convergent with the tyrannid Myiobius erythrurus is falsified. Some similarities in plumage between these species are apparently homologous traits that evolved early in the radiation of the Myiophobus group.

Interspecific territoriality in red-breasted meadowlarks and a method for estimating the mutuality of their participation

1. Three species of red-breasted meadowlarks (Aves, Icteridae, Sturnella) coexist on the pampas of southern Buenos Aires Province, Argentina. The species differ somewhat in size and shape but have very similar color patterns. 2. In the nearly homogeneous habitat provided by wheat fields, S. defilippii and S. militaris superciliaris have nonoverlapping territories that are maintained by interspecific aggression and that are not related to vegetation discontinuity. Maintenance of interspecific territoriality (IST) was not mutual, for the larger species (defilippii) had a much stronger tendency to attack and exclude the smaller species than vice versa. However, once a superciliaris male did establish a territory, it was capable of defending it against defilippii males. A third species, S. loyca, had territories that overlapped those of the other two species, and although the largest of the three, it seldom engaged in interspecific aggression. 3. The observed interspecific aggression seems due to close similarities in plumage and behavior of defilippii and superciliaris, reflecting their close phylogenetic relationship. No evidence has been adduced indicating how or whether the IST is adaptive, and no reason for predicting character convergence emerges from this study. 4. This paper describes a method for quantifying the relative contribution of two or more species to interspecific aggression, including methods for correcting for the actual availability of heterospecific and conspecific males.