1. Ants play a fundamental role in coffee pest control. Despite this, there is a lack of understanding about how landscape configuration and composition regulate the ecosystem service provided by ants in sun coffee farms within highly fragmented landscapes.2. We measured whether landscape structure influences ants' ability to regulate coffee berry borer (CBB) in sun coffee farms in Southeastern Brazil. Considering the ecological interactions between ants and CBB at three different stages of pest control (reduction of CBB presence, CBB infestation, and CBB bean damage), we measured pest control among 10 landscapes that represented a gradual difference in forest and coffee cover. We manipulated ants through exclusion experiments and tested whether interactions between ants and different landscape structure metrics (distance to forest fragments, 2-km-level forest cover, and 300-m-level forest and coffee cover) influenced pest control.3. The presence of ants reduced CBB presence and CBB damage by up to 40%. We show how pest control service indicators change depending on the landscape level. The probability of CBB presence increased with expanding coffee and forest cover at the 300-mlevel but decreased at the 2-km-level. CBB infestation reduced further after 25 m from forest edges, suggesting ants that provide these ecosystem services are adapted to matrix conditions in sun coffee farms. Ants reduced CBB presence, CBB infestation, and CBB damage in landscapes with at least 40% 2-km-level forest cover. Beyond this threshold, there is a turning point for ecological processes involved in pest control. Synthesis and applications.This is the first long-term branch-level exclusion experiment to present strong evidence of ants as efficient providers of pest control in sun coffee farms. We show how landscape structure modulates key ecological processes involved in three different ant-CBB interactions that regulate CBB populations. Forest cover measured at different landscape levels yielded different results for CBB presence, emphasizing the importance of multi-scale studies for landscape management. Considering surrounding forest cover and crop proximity to forest fragments in planning the spatial arrangement of coffee farms can thus both improve pest control as well as contribute to biodiversity conservation. K E Y W O R D S ants, Atlantic Forest, coffee berry borer, coffee borer beetle, coffee farms, ecosystem services, land-use change, pest control S U PP O RTI N G I N FO R M ATI O N Additional supporting information may be found online in the Supporting Information section at the end of the article. How to cite this article: Aristizábal N, Metzger JP. Landscape structure regulates pest control provided by ants in sun coffee farms. J Appl Ecol. 2019;56:21-30. https://doi.

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In the Andes, humid-forest organisms frequently exhibit pronounced genetic structure and geographic variation in phenotype, often coincident with physical barriers to dispersal. However, phylogenetic relationships of clades have often been difficult to resolve due to short internodes. Consequently, even in taxa with well-defined genetic structure, the temporal and geographic sequences of dispersal and vicariance events that led to this differentiation have remained opaque, hindering efforts to test the association between diversification and earth history and to understand the assembly of species-rich communities on Andean slopes. Here, we use mitochondrial DNA and thousands of short-read sequences generated with genotyping by sequencing (GBS) to examine the geographic history of speciation in a lineage of passerine birds found in the humid forest of the Andes, the 'bay-backed' antpitta complex (Grallaria hypoleuca s. l). Mitochondrial DNA genealogies documented genetic structure among clade but were poorly resolved at nodes relevant for biogeographic inference. By contrast, relationships inferred from GBS loci were highly resolved and suggested a biogeographic history in which the ancestor originated in the northern Andes and dispersed south. Our results are consistent with a scenario of vicariant speciation wherein the range of a widespread ancestor was fragmented as a result of geologic or climatic change, rather than a stepping-stone series of dispersal events across pre-existing barriers. However, our study also highlights challenges of distinguishing dispersal-mediated speciation from static vicariance. Our results further demonstrate the substantial evolutionary timescale over which the diverse biota of the Andes was assembled.

We infer phylogenetic relationships, divergence times, and the diversification history of the avian Neotropical antpitta genera Hylopezus and Myrmothera (Grallariidae), based on sequence data (3,139 base pairs) from two mitochondrial (ND2 and ND3) and three nuclear nuclear introns (TGFB2, MUSK and FGB-I5) from 142 individuals of the 12 currently recognized species in Hylopezus and Myrmothera and 5 outgroup species. Phylogenetic analyses recovered 19 lineages clustered into two major clades, both distributed in Central and South America. Hylopezus nattereri, previously considered a subspecies of H. ochroleucus, was consistently recovered as the most divergent lineage within the Grallaricula/Hylopezus/Myrmothera clade. Ancestral range estimation suggested that modern lowland antpittas probably originated in the Amazonian Sedimentary basin during the middle Miocene, and that most lineages within the Hylopezus/Myrmothera clade appeared in the Plio-Pleistocene. However, the rate of diversification in the Hylopezus/Myrmothera clade appeared to have remained constant through time, with no major shifts over the 20 million years. Although the timing when most modern lineages of the Hylopezus/Myrmothera clade coincides with a period of intense landscape changes in the Neotropics (Plio-Pleistocene), the absence of any significant shifts in diversification rates over the last 20 million years challenges the view that there is a strict causal relationship between intensification of landscape changes and cladogenesis. The relative old age of the Hylopezus/Myrmothera clade coupled with an important role ascribed to dispersal for its diversification, favor an alternative scenario whereby long-term persistence and dispersal across an ever-changing landscape might explain constant rates of cladogenesis through time.