James Ackerman
Universidad de Puerto Rico, Rio Piedras, Biology, Faculty Member
The El Verde Field Station in the Luquillo Mountains of Puerto Rico has been the subject of intensive ecological research for more than five decades, focusing on ecosystem processes, food webs, and, most recently, forest dynamics, all of... more
The El Verde Field Station in the Luquillo Mountains of Puerto Rico has been the subject of intensive ecological research for more than five decades, focusing on ecosystem processes, food webs, and, most recently, forest dynamics, all of which require correct identification and naming of plant species. Here, we present an up-to-date list of the vascular plants recorded for the Field Station and the immediate surrounding area of the El Yunque National Forest. The list has been compiled from fieldwork as well as the revision of hundreds of specimens housed at several herbaria. It includes 633 taxa (530 native and 103 exotic) in 121 families and 394 genera. The total number of taxa represents 63.3% of the ~1000 species registered for the entire El Yunque National Forest. Of the native taxa, 172 are trees and shrubs. Sixty species are endemic to Puerto Rico, and five are restricted to El Yunque National Forest. The list is expected to assist those who work at the station as well as to contribute to the knowledge of the flora of the Luquillo Mountains and Puerto Rico.
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... INTRODUCTION The abundance of most tropical insect species changes seasonally (eg, Janzen 1973, Wolda 1977, 1978b, Denlinger 1980, Wolda and Fisk 1981). ... 1969, Williams and Dodson 1972, Janzen 1974, Ackerman, in press). ...
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Seasonal and geographic relationships, and host pollinator specificities are examined for indications of interdependency in the orchid-euglossine bee interaction. The orchids are dependent on the bees for pollination, and their flowering... more
Seasonal and geographic relationships, and host pollinator specificities are examined for indications of interdependency in the orchid-euglossine bee interaction. The orchids are dependent on the bees for pollination, and their flowering seasonality corresponds well with peak activity of ...
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... (Orchidaceae) Samuel Moya and James D. Ackerman ... Interpopula-tion variation was examined by comparing plants from the Rio Grande population with those of three other localities: Puerto Rico, Mun. Dorado, limestone hills N of hwy 2... more
... (Orchidaceae) Samuel Moya and James D. Ackerman ... Interpopula-tion variation was examined by comparing plants from the Rio Grande population with those of three other localities: Puerto Rico, Mun. Dorado, limestone hills N of hwy 2 between km 25.0 and 26.5, ca. ...
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... In animal-pollinated species, pollen grains may lose viability quickly (eg Thomson and Thomson 1992, Wyatt and Broyles 1990), but those of orchid pollinia may survive for long periods (Proctor 1998). ... In: Wyatt R. (ed.) Ecol-ogy... more
... In animal-pollinated species, pollen grains may lose viability quickly (eg Thomson and Thomson 1992, Wyatt and Broyles 1990), but those of orchid pollinia may survive for long periods (Proctor 1998). ... In: Wyatt R. (ed.) Ecol-ogy and evolution of plant reproduction. ...
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A new species of Eurystyles (Orchidaceae: Orchidoideae, Cranichideae, Spiranthinae) is proposed, E. luisortizii Ackerman sp. nov., which is most similar to E. ananassocomos (Rchb.f.) Schltr. from which it differs by a suite of floral... more
A new species of Eurystyles (Orchidaceae: Orchidoideae, Cranichideae, Spiranthinae) is proposed, E. luisortizii Ackerman sp. nov., which is most similar to E. ananassocomos (Rchb.f.) Schltr. from which it differs by a suite of floral traits. This species represents the first confirmed record of the genus for the island of Puerto Rico, bringing the Eurystyles species count for the West Indies to four. Keywords: Cranichideae, Orchidoideae, Puerto Rico flora, Spiranthinae, West Indies orchids
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Orchids constitute one of the most spectacular radiations of flowering plants. However, their origin, spread across the globe, and hotspots of speciation remain uncertain due to the lack of an up-to-date phylogeographic analysis. We... more
Orchids constitute one of the most spectacular radiations of flowering plants. However, their origin, spread across the globe, and hotspots of speciation remain uncertain due to the lack of an up-to-date phylogeographic analysis. We present a new Orchidaceae phylogeny based on combined high-throughput and Sanger sequencing data, covering all five subfamilies, 17/22 tribes, 40/49 subtribes, 285/736 genera, and c. 7% (1921) of the 29 524 accepted species, and use it to infer geographic range evolution, diversity, and speciation patterns by adding curated geographical distributions from the World Checklist of Vascular Plants. The orchids' most recent common ancestor is inferred to have lived in Late Cretaceous Laurasia. The modern range of Apostasioideae, which comprises two genera with 16 species from India to northern Australia, is interpreted as relictual, similar to that of numerous other groups that went extinct at higher latitudes following the global climate cooling during the Oligocene. Despite their ancient origin, modern orchid species diversity mainly originated over the last 5 Ma, with the highest speciation rates in Panama and Costa Rica.
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:Biological invasions can have negative consequences for resident biota, particularly when disease-causing organisms are involved. Austropuccinia psidii, or guava rust, has rapidly spread through the tropics affecting both native and... more
:Biological invasions can have negative consequences for resident biota, particularly when disease-causing organisms are involved. Austropuccinia psidii, or guava rust, has rapidly spread through the tropics affecting both native and non-native Myrtaceae. In Puerto Rico, the rust has become common on Syzygium jambos, an invasive tree native to South-East Asia. What are the drivers of infection, and do refugia exist across a heterogeneous landscape? We address these questions using species distribution modelling and beta regressions. The realized and potential distribution of Syzygium jambos is extensive. The model produced an AUC of 0.88, with land-use categories and precipitation accounting for 61.1% of the variation. Predictability of S. jambos is highest in disturbed habitats, especially in mountainous regions with high precipitation. All 101 trees surveyed and measured across Puerto Rico showed signs of infection to varying extents. Infection severity was consistently associated with annual mean temperature in all top beta regression models, but was also commonly associated with tree size and precipitation variables. We found no safe sites for S. jambos. Many trees were extremely unhealthy and some were dead, suggesting that S. jambos may soon become extinct on the island or reduced to persistent stump sprouts. Native vegetation may benefit from the local demise of S. jambos. While the rust has not jumped to native Myrtaceae, vigilance is required, as host-shifts have occurred in other tropical regions.
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Abstract Population projection matrices are a common means for predicting short- and long-term population persistence for rare, threatened and endangered species. Data from such species can suffer from small sample sizes and consequently... more
Abstract Population projection matrices are a common means for predicting short- and long-term population persistence for rare, threatened and endangered species. Data from such species can suffer from small sample sizes and consequently miss rare demographic events resulting in incomplete or biologically unrealistic life cycle trajectories. Matrices with missing values (zeros; e.g., no observation of seeds transitioning to seedlings) are often patched using prior information from the literature, other populations, time periods, other species, best guess estimates, or are sometimes even ignored. To alleviate this problem, we propose using a multinomial-Dirichlet model for parameterizing transitions and a Gamma for reproduction to patch missing values in these holey matrices. This formally integrates prior information within a Bayesian framework and explicitly includes the weight of the prior information on the posterior distributions. We show using two real data sets that the weight assigned to the prior information mainly influences the dispersion of the posteriors, the inclusion of priors results in irreducible and ergodic matrices, and more biologically realistic inferences can be made on the transition probabilities. Because the priors are explicitly stated, the results are reproducible and can be re-evaluated if alternative priors are available in the future.
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Research Interests: Botany, Plant Ecology, Plant Biology, Biology, Ecology, and 15 morePopulation Dynamics, Population ecology, Puerto Rico, Medicine, Orchids, Population, Population Density, Ecología, Orchidaceae, Conservation of Natural Resources, PPM, Plant Demography, Music Information Dynamics, Reactivity, and Lambda
... Multivariate an-alyses of data from herbarium material have shown that plants from Cuba, Dominican Re-public and Puerto Rico with dissimilar flowering phenologies are more similar to each other with-in islands than they are to... more
... Multivariate an-alyses of data from herbarium material have shown that plants from Cuba, Dominican Re-public and Puerto Rico with dissimilar flowering phenologies are more similar to each other with-in islands than they are to like-phenology types on adjacent islands. ...
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Research Interests: Biology and Pollination
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Research Interests: Biology and Lankesteriana
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ABSTRACTNatural pollination of species belonging to the pantropical orchid genusVanillaremains poorly understood. Based on sporadic records, euglossine bees have been observed visiting flowers of NeotropicalVanillaspecies. Our research... more
ABSTRACTNatural pollination of species belonging to the pantropical orchid genusVanillaremains poorly understood. Based on sporadic records, euglossine bees have been observed visiting flowers of NeotropicalVanillaspecies. Our research aimed at better understanding the pollinator attraction mechanism of the Neotropical speciesVanilla pompona, a crop wild relative with valuable traits for vanilla crop improvement programs. Using video footage, we identified floral visitors and examined their behavior. The flowers ofV. pomponaattractedEulaema cingulatamales, which distinctively displayed two behaviors: floral scent collection and nectar search; with the latter leading to pollen removal. Morphological measurements of floral and visitor traits showed that otherEulaemaspecies may also act as potential pollinators. Additionally, we recorded natural fruit set in three populations and over a period of two years, tested for nectar presence and analyzed floral fragrances through gas chromatog...
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Orchidaceae show remarkable diversity in pollination strategies, but how these strategies vary globally is not entirely clear. To identify regions and taxa that are data-rich and lend themselves to rigorous analyses or are data-poor and... more
Orchidaceae show remarkable diversity in pollination strategies, but how these strategies vary globally is not entirely clear. To identify regions and taxa that are data-rich and lend themselves to rigorous analyses or are data-poor and need attention, we introduce a global database of orchid reproductive biology. Our database contains > 2900 species representing all orchid subfamilies and 23 of 24 tribes. We tabulated information on habit, breeding systems, means of pollinator attraction and the identity of pollinators. Patterns of reproductive biology by habit, geography and taxonomy are presented graphically and analysed statistically . On the basis of our database, most orchid species sampled are pollinator dependent (76%) and self-compatible (88%). Pollinator attraction based on rewards occurs in 54% of the species, whereas 46% use some means of deceit. Orchids generally have highly specific pollinator interactions (median number of pollinator species = 1). Nonetheless, on average, specificity is lower for species offering rewards, occurring in multiple continental regions or Northern America (as defined by their Taxonomic Database Working Group Level 1 regions). Although our database reveal impressive knowledge gains, extensive gaps in basic observations of orchid reproductive biology exist, particularly in tropical regions and diverse lineages of fly-pollinated species. The database is expected to facilitate targeted studies, further elucidating the ecological and evolutionary drivers of orchid diversity.
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... However, in other situations, reproduction in native plants is reduced when exotic A. mellifera visits (Aizen & Feinsinger 1994; Roubik 1996; Gross ... Based on the germination of seeds in time (23 days) and using the Kaplan and... more
... However, in other situations, reproduction in native plants is reduced when exotic A. mellifera visits (Aizen & Feinsinger 1994; Roubik 1996; Gross ... Based on the germination of seeds in time (23 days) and using the Kaplan and Meier method, we estimated one survival function S ...
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Page 1. Biotic versus abiotic pollination in Oeceoclades maculata (Lindl.) Lindl. (Orchidaceae) psbi_330 1..10 JOÃO MRBV AGUIAR,* LUDMILA M. PANSARIN, JAMES D. ACKERMAN and EMERSON R. PANSARIN* *University of São Paulo, Department of... more
Page 1. Biotic versus abiotic pollination in Oeceoclades maculata (Lindl.) Lindl. (Orchidaceae) psbi_330 1..10 JOÃO MRBV AGUIAR,* LUDMILA M. PANSARIN, JAMES D. ACKERMAN and EMERSON R. PANSARIN* *University of São Paulo, Department of Biology, Av. ...
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... Page 2. 56 E. Ortiz-Barney and JD Ackerman: The cost of selfing double that of the outcrossers. Thus the advantage a selfing mother has is less than two-fold (Lloyd 1980; Uyenoyama 1984, 1986; Jarne and Charlesworth 1993). ...
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Research Interests: Botany, Evolutionary Biology, Microbiology, Geography, Biology, and 15 moreEcology, Medicine, Molecular Ecology, Biological Sciences, Orchids, Orchidaceae, Germination, Analysis of Variance, Phylogenetic Tree, Mycorrhizae, Base Sequence, Likelihood Functions, BASIDIOMYCOTA, Molecular Sequence Data, and Internal transcribed spacer
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... Correspondence: Susan Aragón,. ... Sin embargo, los adultos de ambos sitios tuvieron los menores valores de I MS indicando que los adultos tienen una ... de su hospedero predilecto, sin embargo factores específicos de cada sitio que... more
... Correspondence: Susan Aragón,. ... Sin embargo, los adultos de ambos sitios tuvieron los menores valores de I MS indicando que los adultos tienen una ... de su hospedero predilecto, sin embargo factores específicos de cada sitio que afectan la sobrevivencia de las plántulas ...
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... Under these conditions, natural selection should be detectable among plants that vary in rewards. As in most orchids studied, reproduction in the epiphytic Comparettia falcata is severely pollination limited (Rodriguez-Robles et al.... more
... Under these conditions, natural selection should be detectable among plants that vary in rewards. As in most orchids studied, reproduction in the epiphytic Comparettia falcata is severely pollination limited (Rodriguez-Robles et al. ... equivalents, Rodriguez-Robles et al. 1772). ...
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... For their help in the field we would like to thank Jennifer Fernández-Betancourt, Erik Rivera-Marchand, Mayela Alsina, Kristy Barksdale, José Fumero, Luis F. Castillo, and Gretchen Rivera. Finally we thank Luzelvia Díaz for her... more
... For their help in the field we would like to thank Jennifer Fernández-Betancourt, Erik Rivera-Marchand, Mayela Alsina, Kristy Barksdale, José Fumero, Luis F. Castillo, and Gretchen Rivera. Finally we thank Luzelvia Díaz for her artistic services. ... Wadsworth, and J. Marrero. 1967. ...
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Research Interests: Biology, Ecology, Invasive Species, Puerto Rico, Seed germination, and 12 moreBiological invasions, Biological Sciences, Relative Growth Rate, Environmental Sciences, Life Cycle, Spatial Distribution, Fruit Production, Spatial Relationships, Native Species, Leaf Area, Mean Germination Time, and Tree Species
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Orchidaceae show remarkable diversity in pollination strategies, but how these strategies vary globally is not entirely clear. To identify regions and taxa that are data-rich and lend themselves to rigorous analyses or are data-poor and... more
Orchidaceae show remarkable diversity in pollination strategies, but how these strategies vary globally is not entirely clear. To identify regions and taxa that are data-rich and lend themselves to rigorous analyses or are data-poor and need attention, we introduce a global database of orchid reproductive biology. Our database contains > 2900 species representing all orchid subfamilies and 23 of 24 tribes. We tabulated information on habit, breeding systems, means of pollinator attraction and the identity of pollinators. Patterns of reproductive biology by habit, geography and taxonomy are presented graphically and analysed statistically. On the basis of our database, most orchid species sampled are pollinator dependent (76%) and self-compatible (88%). Pollinator attraction based on rewards occurs in 54% of the species, whereas 46% use some means of deceit. Orchids generally have highly specific pollinator interactions (median number of pollinator species = 1). Nonetheless, on av...