Patricia Escalante

Out of Amazonia again and again: episodic crossing of the Andes promotes diversification in a lowland forest flycatcher

Most Neotropical lowland forest taxa occur exclusively on one side of the Andes despite the availability of appropriate habitat on both sides. Almost all molecular phylogenies and phylogenetic analyses of species assemblages (i.e. area cladograms) have supported the hypothesis that Andean uplift during the Late Pliocene created a vicariant barrier affecting lowland lineages in the region. However, a few widespread plant and animal species occurring in lowland forests on both sides of the Andes challenge the generality of this hypothesis. To understand the role of the Andes in the history of such organisms, we reconstructed the phylogeographic history of a widespread Neotropical flycatcher (Mionectes oleagineus) in the context of the other four species in the genus. A molecular phylogeny based on nuclear and mitochondrial sequences unambiguously showed an early basal split between montane and lowland Mionectes. The phylogeographic reconstruction of lowland taxa revealed a complex history, with multiple cases in which geographically proximate populations do not represent sister lineages. Specifically, three populations of M. oleagineus west of the Andes do not comprise a monophyletic clade; instead, each represents an independent lineage with origins east of the Andes. Divergence time estimates suggest that at least two cross-Andean dispersal events post-date Andean uplift.

The MexBOL initiative

In 2005, Mexican researchers were invited to participate in the Barcode of Life Initiative. A few researchers showed interest in the initiative then, and in 2007, Paul Hebert from the University of Guelph in Canada came to Chetumal and Mexico City and presented his proposal to the scientific community of Mexico. Initially there were mixed feelings, especially because of the complexities of plant genetic marker development and concerns regarding the traditional practice of taxonomy along with the lack of support for scientific collections, but most researchers showed a strong interest. Paul Hebert was impressed with the enthusiasm shown by researchers and by the research infrastructure for biodiversity studies that Mexico already has. In 2007, Paul Hebert also contacted Mexican officials in two relevant government agencies: CONACYT, the National Council on Science and Technology, and CONABIO, the National Commission for Knowledge and Use of Biodiversity. Officials from CONACYT, Mtro. Juan Carlos Romero-Hicks and Dr Antonio de la Pena, showed enthusiasm for the initiative and decided to give their full support in Mexico. Dr Jose Sarukhan from CONABIO was also positive about this prospect. In the meantime, three groups of researchers with their directors also approached CONACYT to express their interest in the Barcode of Life Project. These research groups were affiliated with three relevant institutions: the Institute of Biology at the Universidad Nacional Autonoma de Mexico (UNAM) which houses many important biological specimen collections in Mexico; El Colegio de la Frontera Sur (ECOSUR), whose academic community has developed a strong interest in DNA barcoding, and which also houses regional collections; and the Centro de Investigaciones Biologicas del Noroeste (CIBNOR), which also showed a strong interest in the initiative. These three academic institutions became local nodes for the MexBOL campaign and together with CONABIO form the basis of this initiative. With basic funding support by CONACYT, researchers and students working on Mexican biodiversity are the main developers of these nodes. The year 2009 was quite important for the MexBOL initiative. CONACYT formalized their support through an official network of researchers and a network committee, and this agency also gave strong support for the organization of the Third International Barcode of Life Conference hosted by the Institute of Biology of UNAM in Mexico City on 7–13 November 2009, and organized by the Consortium for the Barcode of Life (CBoL) based at the Smithsonian Institution. During the conference, a symposium on the Mesoamerican Barcode of Life was held. Several presentations were given by institutional or country representatives (e.g. IBUNAM, ECOSUR, Guatemala, Nicaragua), and other presentations were offered by individual researchers including guests, with the topics ranging from sea life to fungi, and from planning projects such as medicinal plants to more advanced programs such as the Guanacaste project in Costa Rica developed by Daniel H. Janzen and his colleagues. Consequently, the participants of the Mesoamerican Barcode of Life Symposium were invited to present their work in a special issue of the journal Mitochondrial DNA. We hope that the papers produced from this symposium

The Importance, Effects, and Ethics of Bird Collecting

— 690 — The Auk, Vol. 127, Number 3, pages 690−695. ISSN 0004-8038, electronic ISSN 1938-4254.  2010 by The American Ornithologists’ Union. All rights reserved. Please direct all requests for permission to photocopy or reproduce article content through the University of California Press’s Rights and Permissions website, http://www.ucpressjournals. com/reprintInfo.asp. DOI: 10.1525/auk.2010.09199 Kevin WinKer,1,8 J. Michael reed,2 Patricia escalante,3 robert a. asKins,4 carla cicero,5 Gerald e. houGh,6 and John bates7

Evolutionary history of a prominent North American warbler clade: The Oporornis-Geothlypis complex

The avian genera Oporornis and Geothlypis are thought to represent a single lineage of closely related New World wood-warbler (AOU Family Parulidae) species. Phylogenetic relationships within this assemblage have not yet been addressed using molecular genetic methods. We used sequence data from three mitochondrial (mtDNA) genes (cytochrome b, ND2, and control region) to reconstruct an hypothesis of relationships for this group. Our ingroup sampling included 34 individuals representing all currently recognized Oporornis (4 spp.) and Geothlypis (9 spp.) species. Our results indicate that Geothlypis is paraphyletic with respect to Oporornis formosus. The four members of Oporornis do not form a clade but instead comprise a grade at the base of the Oporornis-Geothlypis topology. Two species within Geothlypis are polyphyletic. The Costa Rican form of G. aequinoctialis is embedded within the Neotropical G. semiflava complex, and the widespread North American form G. trichas consists of at least two groups, each having a closer affinity to other Geothlypis species than with each other. Five Geothlypis species differ from one another on average by about 2% uncorrected (cytochrome b) divergence, indicating a rapid and recent radiation within this genus. Our phylogenetic hypothesis for this assemblage indicates that morphological characters such as size and plumage brightness that have traditionally defined relationships with Geothlypis are not concordant with molecular data. Most members of Geothlypis are sedentary whereas all members of Oporornis are long-distance Nearctic migrants. Our topology suggests that Geothlypis is derived from a migrant, Oporornis-like ancestor that ceased migration and established itself as a sedentary breeding population in the Neotropics. We speculate that an ecological switch from forested to more open habitats at this time led to range expansion and diversification in this new lineage.

Continental-scale analysis reveals deep diversification within the polytypic Red-crowned Ant Tanager (Habia rubica, Cardinalidae).

We explored the phylogeographic patterns of intraspecific diversity in the Red-crowned Ant Tanager (Habia rubica) throughout its continent-wide distribution, in order to understand its evolutionary history and the role of evolutionary drivers that are considered to promote avian diversification in the Neotropics. We sampled 100 individuals of H. rubica from Mexico to Argentina covering the main areas of its disjunct distribution. We inferred phylogenetic relationships through Bayesian and maximum parsimony methodologies based on mitochondrial and nuclear markers, and complemented genetic analyses with the assessment of coloration and behavioral differentiation. We found four deeply divergent phylogroups within H. rubica: two South American lineages and two Mexican and Middle American lineages. The divergence event between the northern and southern phylogroups was dated to c. 5.0 Ma, seemingly related to the final uplift of the Northern Andes. Subsequently, the two South American phylogroups split c. 3.5 Ma possibly due to the development of the open vegetation corridor that currently isolates the Amazonian and Atlantic forests. Diversification throughout Mexico and Middle America, following dispersion across the Isthmus of Panama, was presumably more recent and coincident with Pleistocene climatic fluctuations and habitat fragmentations. The analyses of vocalizations and plumage coloration showed significant differences among main lineages that were consistent with the phylogenetic evidence. Our findings suggest that the evolutionary history of H. rubica has been shaped by an assortment of diversification drivers at different temporal and spatial scales resulting in deeply divergent lineages that we recommend should be treated as different species.

Decadal changes and delayed avian species losses due to deforestation in the northern Neotropics

How avifauna respond to the long-term loss and fragmentation of tropical forests is a critical issue in biodiversity management. We use data from over 30 years to gain insights into such changes in the northernmost Neotropical rainforest in the Sierra de Los Tuxtlas of southern Veracruz, Mexico. This region has been extensively deforested over the past half-century. The Estación de Biología Tropical Los Tuxtlas, of the Universidad Nacional Autónoma de México (UNAM), protects a 640 ha tract of lowland forest. It became relatively isolated from other forested tracts between 1975 and 1985, but it retains a corridor of forest to more extensive forests at higher elevations on Volcán San Martín. Most deforestation in this area occurred during the 1970s and early 1980s. Forest birds were sampled on the station and surrounding areas using mist nets during eight non-breeding seasons from 1973 to 2004 (though in some seasons netting extended into the local breeding season for some species). Our data suggested extirpations or declines in 12 species of birds subject to capture in mist nets. Six of the eight species no longer present were captured in 1992–95, but not in 2003–2004. Presence/absence data from netting and observational data suggested that another four low-density species also disappeared since sampling began. This indicates a substantial time lag between the loss of habitat and the apparent extirpation of these species. Delayed species loss and the heterogeneous nature of the species affected will be important factors in tropical forest management and conservation.

Tropical montane nymphalids in Mexico: DNA barcodes reveal greater diversity

Materials and methods: DNA sequences obtained for the Barcode of Life library in the All Lepidoptera Campaign project Nymphalidae of Central Mexico were analyzed as a test of species limits and to explore possible phylogenetic groupings in the Preponini tribe. Using specimens in the National Insect Collection of the Instituto de Biología of the Universidad Nacional Autónoma de México, 78 specimens were assayed for cytochrome oxidase c subunit 1. Results: Disregarding the missing data, there were 458 conserved sites, 200 variable sites and 187 parsimony-informative sites. The neighbor-joining and maximum likelihood analyses indicate that none of the three genera of Preponini as currently circumscribed are reciprocally monophyletic. As per species limits, high levels of barcode variation in the Prepona deiphile complex suggest the existence of at least two new endemic species to Mexico. The divergent taxa were escalantiana from the Tuxtlas region in Veracruz, and ibarra from Sierra Madre del Sur in the Pacific states of southern Mexico. The genetic distance in the CO1 fragment between them and the other deiphile populations ranged from 2.7 to 8.0%. Conclusion: We recommend that morphological data need to be re-examined and that additional molecular data for species ought to be gathered before a particular biogeographic model can be proposed for the group in Mesoamerica.

Film Documentation of the Probably Extinct Imperial Woodpecker (Campephilus imperlalis)

ABSTRACT. The Imperial Woodpecker (Campephilus imperialis) of Mexico—the largest woodpecker in the world—probably became extinct in the late 20th century, without known documentation of the species in life. We describe a recently discovered 16-mm color film of an Imperial Woodpecker taken in 1956 by William L. Rhein. The film documents climbing strides, launches, flights, and foraging of one female Imperial Woodpecker. For perches and foraging the woodpecker used dead or recently dead Durango Pines (Pinus durangensis). Trunks of perch and foraging trees were of the largest diameters available in this tree species. After allowing for possible inaccuracies in the frame speed of the film, we found that the Imperial Woodpecker had slow climbing strides and a fast wingflap rate compared with other woodpeckers. Following landmarks documented during the 1956 expedition, we identified and surveyed the film site in 2010. The site was in coniferous forest in lightly undulating terrain at 2,700–2,900 m elevation. In 1956, the area was oldgrowth forest with abundant large and dead trees. By 2010, the area had been logged multiple times. Interviews with local people indicated that Imperial Woodpeckers had disappeared from the region by 1960 and that they were killed by hunting and perhaps through poisoning instigated by logging interests. Human persecution and the logging of large pines for timber and of dead trees for pulp were likely principal factors in the extinction process of the Imperial Woodpecker.

Brood Sex Ratio of the Lilac-crowned Parrot (Amazona finschi)

Abstract Evolutionary theory predicts birds should adjust the sex ratio of their broods in response to external factors that differentially affect the reproductive value of each sex. We examined the brood sex ratio in the Lilac-crowned Parrot (Amazona finschi) in relation to climate, hatching date, and hatching order. We used polymerase chain reaction amplifications to identify the gender of 66 nestlings from 32 clutches spanning 7 years. There was a tendency to produce more female offspring in years of high nestling survival following high rainfall with a slight female-bias in third-hatched nestlings. We found no significant associations between brood sex ratio and rainfall, hatching date, or hatching order within clutches. Our results suggest the examined factors provide insufficient differential costs or benefits of offspring gender to promote sex ratio bias in this monomorphic species.

PHENOLOGY, HABITAT USE, AND NESTING OF THE RED-BREASTED CHAT (GRANATELLUS VENUSTUS)

Abstract From March 1999 to August 2000, we conducted monthly mist netting in the Chamela-Cuixmala Biosphere Reserve, Jalisco, Mexico to document the phenology and habitat use of the Red-breasted Chat (Granatellus venustus). We collected information on its nesting biology during the breeding season of 2001. Chats (n = 116) were caught throughout the 18 months of the study; however, far fewer captures occurred during the dry season than during the wet season. Our capture data revealed that chats made greater use of deciduous (n = 88) than semi-deciduous forest (n = 28); there were no interactions among forest type, season, and gender. Birds in breeding condition were captured June–September and molting birds were captured August– October. We found 10 cup-shaped nests in June and July. Nests were 48–103 cm above ground in saplings ≤2 m high. Clutch size was 3–4 and only the female incubated. The incubation period was 14 days, and we estimated the nestling period to be approximately 8–10 days. Of eight nests found with eggs or young, three were depredated during the egg stage, three during the nestling stage, and two were successful.