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Estimates of species extinction due to human impact on tropical forests have previously been based on the relationship between species number and area. Here we use a different approach to estimate loss of tree species in the Atlantic forest of northeast Brazil. We evaluate the characteristics of plant species, their avian dispersers and the distribution of the forest remnants on the landscape to estimate that about 33.9% of tree species in this region will become extinct on a regional scale. Because northeast Brazil is the most threatened sector of South American Atlantic forest, our results highlight the need to change the current conservation paradigm for this region. Rather than focus on the creation of isolated reserves in any medium-to-large forest remnant, a bioregional planning approach is urgently required to rescue this unique biota from extinction.

The 735,000-km 2 Caatinga is a mosaic of thorn scrub and seasonally dry forests, with more than 2000 species of vascular plants, fishes, reptiles, amphibians, birds, and mammals. Endemism in these groups varies from 7% to 57%. Inappropriate land use has already caused serious environmental damage and accelerating desertification, which is currently threatening about 15% of the region. Moreover, the rich and diversified biota of the Caatinga is poorly protected: only 11 reserves (<1% of the region) are strictly protected areas. A conservation strategy for the Caatinga biota should be designed to (1) avoid further habitat loss and desertification, (2) maintain key ecological services necessary for improving the living standards of the rural population, and (3) promote the sustainable use of the region's natural resources. Implementing an effective conservation agenda for the Caatinga is not an easy task but, with creativity and consistent financial support, it should be possible to nurture this unique biome and guarantee the preservation of its rich and diversified fauna and flora, and, with this, the well-being of its rural populations.Cambiando el Curso de la Conservación de Biodiversidad en la Caatinga del Noreste de Brasil Resumen: La Caatinga, con 735,000 km 2 , es un mosaico arbustos espinosos y de bosques secos estacionalmente, con más de 2000 especies de plantas vasculares, peces, reptiles, anfibios, aves y mamíferos. El endemismo en estos grupos varía entre 7% y 57%. El uso inadecuado del suelo ha causado serios daños ambientales y acelerado la desertificación, que actualmente amenaza a 15% de la región. Más aun, la rica y diversificada biota de la Caatinga esta deficientemente protegida: solo 11 reservas (<1% de la región) sonáreas estrictamente protegidas. Se debe diseñar una estrategia de conservación para la biota de la Caatinga para (1) evitar mayor pérdida de hábitat y desertificación; (2) mantener servicios ecológicos claves, necesarios para mejorar los estándares de vida y (3) promover el uso sustentable de los recursos naturales de la región. La instrumentación de una agenda de conservación efectiva para la Caatinga no es una tarea sencilla pero, con creatividad y apoyo financiero consistente, sería posible nutrir a este biomaúnico y garantizar la preservación de su rica y diversificada fauna y flora, y, con esto, el bienestar de sus poblaciones rurales.

Amazonia is the largest and most diverse of the tropical forest wilderness areas. Recent compilations indicate at least 40,000 plant species, 427 mammals, 1294 birds, 378 reptiles, 427 amphibians, and around 3,000 fishes. Not homogeneous in its plant and animal communities, it is an archipelago of distinct areas of endemism separated by the major rivers. Biogeographic studies of terrestrial vertebrates have identified eight such areas in the Brazilian Amazon: Tapajós, Xingú, and Belém (all in Brazil); Rondônia (mostly in Brazil); and portions of Napo, Imeri, Guiana, and Inambari. They range in size from more than 1.7 million km 2 (Guiana) to 199,211 km 2 (Belém). Forest loss in each ranges from 2% to 13% of their area, except for Xingu (nearly 27% lost) and Belém, (now only about one-third of its forest remains). Napo, Imeri, and Guiana have >40% of their lands in protected areas, Inambari, Rondônia, Tapajós, and Xingu between 20% and 40%, and Belém <20%. Strictly protected areas in each, however, are limited-from 0.28% to 11.7%. Areas of endemism should be the basic geographic unit for the creation of conservation corridors of contiguous protected areas, providing broad connectivity on both margins and within the interior of areas of endemism. The aim is to build a conservation system that is large and resilient enough to circumvent global changes, accommodate improved living standards for local populations, conserve biodiversity, and safeguard the ecological services forests and rivers provide. Elected leaders are now realizing that the traditional economy based on cattle ranching and logging is unsustainable. Deforestation proceeds apace, but the federal government is implementing the Protected Areas Programme for Amazonia, which seeks to protect 50 million ha, and a number of state governments are now active in creating protected areas and incorporating appropriate conservation measures in their development plans. El Destino de lasÁreas de Endemismo Amazónicas Resumen: La Amazonía es elárea de bosque tropical más grande y diversa. Compilaciones recientes indican por lo menos 40,000 especies de plantas, 427 de mamíferos, 1294 de aves, 378 de reptiles y alrededor de 3,000 de peces. No es homogénea en sus comunidades plantas y animales, sino que es un archipiélago de distintaś areas de endemismo separadas por los ríos principales. Estudios biogeográficos de los vertebrados terrestres han identificado ocho de esasáreas en la Amazonía Brasileña: Tapajós, Xingú y Belém (todas en Brasil), Rondônia (la mayor parte en Brasil) y porciones de Napo, Imeri, Guyana e Inambari. Varían en extensión desde más de 1.7 millones de km 2 (Guyana) hasta 199,211 km 2 (Belém). La pérdida de bosque en cada una varía de 2% a 13% de su superficie, excepto Xingu (casi 27%) y Belém (solo permanece cerca de una tercera parte de su bosque). Napo, Imeri y Guyana tienen >40% de su extensión enáreas protegidas, Inambari, Rondônia, Tapajós y Xingu entre 20% y 40% y Belém <20%. Sin embargo, lasáreas estrictamente protegidas en cada una son lim...

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From towers constructed at the interface between second‐growth forest and an active and an abandoned pasture, we observed inter‐habitat movements of fruit‐eating birds in eastern Amazônia. The abandoned pasture was composed of grasses and forbs with a scattering of shrubs and small trees. The active pasture contained a low, uniform bed of grass. A total of 47 frugivorous bird species was recorded in the second‐growth forest. We observed that 18 of these species frequented the adjacent abandoned pasture but only 3 were found in the adjacent active pasture. Fruit‐eating birds flying from second‐growth forest typically spent only a few minutes in the abandoned pasture, and their movements were generally restricted to a pasture belt of 1–80 m along the border with the second‐growth forest. Most inter‐habitat movement occurred during the rainy season, which coincided with a peak in fruit availability in the abandoned pasture. Just three bird species, Ramphocelus carbo, Tachyphonus rufus, and Thraupis episcopus, accounted for an estimated 70% of the total movement of frugivores between the second‐growth forest and the abandoned pasture. All three species spent most of their time in the abandoned pasture foraging on shrubs and trees but exhibited differences in their preference for specific habitat elements and in their seed‐defecation habits. An understanding of bird behaviors in altered landscapes provides important information to planners and policy makers concerned with protecting regional biodiversity and maintaining landscape integrity. This research provides a rationale for placing limits on the size of clearings in the Brazilian Amazon.

Aim To use parsimony analysis of endemicity and cladistic analysis of distributions and endemism to evaluate two hypotheses addressing biogeographical relationships among Amazonia, the Caatinga forest enclaves, Pernambuco Centre and the southern Atlantic Forest.Location North-eastern Brazil, South America.Methods To find the most parsimonious areagram we analysed a matrix composed of the presence (1) or absence (0) of 745 taxa (i.e. 293 genera and 452 species of woody plants) within 16 localities belonging to the four large regions addressed in this study.Results One most parsimonious areagram was found and it shows a basal separation between the southern Atlantic Forest and all other regions. This break is followed by a separation between all Caatinga forest enclaves (except Baturité) from a cluster composed of Baturité, the Pernambuco Centre and Amazonia. In this cluster, the most basal separation isolates Baturité from the cluster formed by localities from Amazonia and the Pernambuco Centre. The biogeographical relationships among sites could not be explained by either a random distribution of species among sites or by the geographical distance between sites.Main conclusions We found strong cladistic signal within the raw distribution and phylogenetic data used in our analysis, indicating structured species assemblages in the surveyed localities. They have resulted from the fragmentation of an ancestral biota that was once widely distributed in the region. Our results also support the hypothesis that Atlantic Forest is not a biogeographically natural area, because the Pernambuco Centre is more closely related to Amazonia than to the southern Atlantic Forest. Finally, our data do not support the notion that Caatinga forest enclaves comprise a single biogeographical region, because one Caatinga forest enclave (Baturité) is much more closely related to the cluster formed by Amazonia and the Pernambuco Centre than to other sites. These relationships suggest the occurrence of forest connections between Amazonia and the Atlantic Forests across Caatinga during several periods of the Tertiary and Quaternary. However, palaeoecological data currently available for the Caatinga region are still scarce and do not have either the spatial or temporal resolution required to reconstruct the history of connections among the forests in north-eastern Brazil.

The distributions of 51 non‐human primate species are used for Parsimony Analysis of Endemicity (PAE) to determine the relationships among 14 interfluvial regions in the Amazon basin, South America. Two most parsimonious cladograms were found. The strict consensus tree of these cladograms suggests an early separation between Lower Amazonia (eastern) and Upper Amazonia (western). The major clusters of interfluvial regions identified in the PAE cladogram are congruent with the areas of endemism delimited for birds. When interfluvial regions are converted into avian areas of endemism, the PAE cladogram is congruent with one of the two general areas cladograms suggested for Amazonia based on phylogenies of several clades of forest birds. Our analysis suggests that PAE can be used as a tool to objectively identify areas of endemism at an intra‐continental scale as well as to make historical inferences. However, the value of a PAE cladogram in this latter application should be always evaluated by congruence with area cladograms built upon cladistic biogeography procedures.