Raymond L TremblayUniversity of Puerto Rico at Humacao | UPRH · Department of Biology
Raymond L Tremblay
PhD
About
128
Publications
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Introduction
I'm an Evolutionary Ecologist with interest in Population dynamics. As a quantitative biologist I have developed extensive skills as a Data Scientist. I have a wide interest in questions that attempts to explain evolutionary processes that result in cladogenesis through Natural Selection and Genetic Drift.
Additional affiliations
Education
January 1992 - May 1996
September 1987 - May 1991
Publications
Publications (128)
Objectives
To estimate the epidemiology of sarcoidosis in Puerto Rico.
Methods
Patients with a diagnosis of sarcoidosis between January 2015 and December 2018 were selected from the Puerto Rico Health Insurance Administration Administración de Seguros de Salud de Puerto Rico claims database. The International Classification of Diseases-Tenth Revis...
Worldwide, thousands of orchid species are harvested from the wild. Widespread legal and illegal unsustainable
trade has contributed to the decline of many species. However, there is also evidence of long-term, sustainable
wild harvest of some orchid species that contribute to local livelihoods and cultural traditions. There is a clear
need to help...
Artificial selection is the process by which humans change morphological and genetic character- istics of species through selection of “favored” characters. Although the gray literature suggests the process is occurring in orchids held in ex situ collections, there is limited evidence of this in the scientific literature. There is a perspective amo...
Based on several regression specifications that control for a host of covariates, this article demonstrates that the quantity of undergraduate research experience was by far the most important determinant for increased graduation rates at a 100% Hispanic-serving institution. Our finding also shows a causal relationship confirmed by propensity score...
Stage-based demographic methods, such as matrix population models (MPMs), are powerful tools used to address a broad range of fundamental questions in ecology, evolutionary biology, and conservation science. Accordingly, MPMs now exist for over 3,000 species worldwide. These data are being digitised as an ongoing process and periodically released i...
Attrition rates in the first two years of graduate school are high and ∼50% higher for underrepresented students. Here we evaluate an online group coaching intervention using a controlled and an experimental group to determine its impact on skills that are likely predictors of student success, namely the Hallmark of Success indices developed by the...
We explore phorophyte suitability for germination and establishment of the epiphytic orchid, Psychilis kraenzlinii. We found that the orchid grows on a subset of the available tree species and shows pref- erence for the endemic Machaonia portoricensis (Rubiaceae). The orchid preferred trees with smoother bark, high water holding capacity and low wa...
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 s...
What grows where? Knowledge about where to find particular species in nature must have been key to the survival of humans throughout our evolution. Over time, and as people colonised new land masses and habitats, interactions with the local biota led to a wealth of combined traditional and scientific wisdom about the distributions of species and th...
Puerto Rico has experienced multiple introductions of Psittaciformes that have established self-sustaining populations, and the White-winged Parakeet (Brotogeris versicolurus) has been considered the most successful introduced psittacine species on the island. In this study, we evaluated their population size, calculated growth rates, and estimated...
Orchids constitute one of the most spectacular radiations of flowering plants. However, their geographical origin, historical spread across the globe, and hotspots of speciation remain uncertain due to the lack of a broad phylogenomic framework.
⍰ We present a new Orchidaceae phylogeny based on high-throughput and Sanger sequencing datasets, coveri...
Stage‐based demographic methods, such as matrix population models (MPMs), are powerful tools used to address a broad range of fundamental questions in ecology, evolutionary biology and conservation science. Accordingly, MPMs now exist for over 3000 species worldwide. These data are being digitised as an ongoing process and periodically released int...
The AIDS pandemic on average took a life every minute in 2021 despite effective HIV treatment and tools to prevent, detect, and treat opportunistic infections. The objective of this study was to estimate the average life expectancy and life years lost (LYL) in people diagnosed with HIV or AIDS in Puerto Rico from 2000-2020. The epidemiological desi...
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 speci...
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 speci...
The tropical Andean landscape has been dramatically transformed over the last century with remaining native forest limited to small fragments within a heterogeneous matrix of crops, cattle pastures, and urban environments. We aimed to explore the impact of habitat transformation on the population dynamics in an endemic twig epiphytic orchid located...
This list is the basis for a paper that we have submitted, "Beyond the various contrivances by which orchids are pollinated: global patterns in orchid pollination biology."
Abstract:
The Orchidaceae shows remarkable diversity in pollination strategies but how these strategies vary globally is not entirely clear. To identify regions and taxa that a...
Puerto Rico has experienced multiple introductions of Psittaciformes which have established self-sustaining populations, and the White-winged parakeets (Brotogeris versicolurus) has been considered the most successful invasive psittacine species in the island. In this study, we evaluated their population size, calculated growth rates and estimated...
The Post-Hurricane Distress Scale (PHDS) was developed to assess mental health risk in the aftermath of hurricanes. We derive both disorder-specific cutoff values and a single nonspecific cutoff for the PHDS for field use by disaster relief and mental health workers. Data from 672 adult residents of Puerto Rico, sampled 3 to 12 months after Hurrica...
Ecólogo, Estadístico y Profesor UPR en Humacao M uchos de los estudiantes que entran a las universidades en Puerto Rico no se gradúan. La Universidad de Puerto Rico, recinto de Cayey gradúa cerca de la mitad de los alumnos que se matriculan. Si piensa que es poco, sepa que en las univer-sidades privadas las tasas de graduación son muy inferiores a...
High levels of within-individual variation (WIV) in reiterative components in plants such as leaves, flowers, and fruits have been shown to increase individual fitness by multiple mechanisms including mediating interactions with natural enemies. This relationship between WIV and fitness has been studied almost exclusively in plant systems. While an...
We estimated population densities of the red-bellied racer (Alsophis rufiventris) on the Caribbean island of St. Eustatius in 2011, 2018 and 2019 to determine the likely influence of hurricanes Irma and Maria (September 2017), in addition to evaluating abiotic parameters which may be correlated with its presence. Surveys were conducted at seven sit...
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 trajec-tories. Matrices with m...
This is a brief obituary for one of the most influential scientists in Orchidology and Neotropical Botany published in Orchid Research Newsletter #76 published out of Royal Botanic Gardens, Kew.
Calaway H. Dodson has had a significant impact on the development of orchid biology and Neotropical botany. His academic history and what he has accomplished both in science and the academic lineage that he fostered is summarized
Background: Sarcoidosis is a systemic granulomatous and inflammatory disorder with significant
variability in ethnicity and geographical distribution. There is no descriptive data about the
epidemiology of the disease among the geographically isolated Puerto Rican population.
Objective: To estimate the incidence, prevalence, distribution, and healt...
Aim
Understanding the factors driving the diversity of alien and native species on islands is crucial for predicting the spread of alien species and for proposing management practices to protect the unique native biodiversity that often occurs in insular ecosystems. The main objective of this study was to evaluate whether native and alien plant spe...
Premise of research. Small populations are intrinsically more vulnerable to population decline and extinction. Such populations may be most susceptible when distributed on small islands, which suffer disproportionately more from human influences, both directly and indirectly. Nevertheless, small native populations that occur on multiple islands may...
The long‐term fate of populations experiencing disequilibrium conditions with their environment will ultimately depend on how local colonization and extinction dynamics respond to abiotic conditions (e.g. temperature and rainfall), dispersal limitation and biotic interactions (e.g. competition, facilitation or interactions with natural enemies). Un...
Soil microbial communities are an important component of biological diversity and terrestrial ecosystems which is responsible for processes such as decomposition, mineralization of nutrients, and accumulation of organic matter. One of the factors that provide information on the mechanisms regulating biodiversity is spatial scaling. We characterized...
News article about our paper "From the cage to the wild: introductions of Psittaciformes to Puerto Rico" authored by Gerardo E. Alvarado León from El Nuevo Día.
https://www.researchgate.net/publication/328612723_From_the_cage_to_the_wild_introductions_of_Psittaciformes_to_Puerto_Rico
Este libro es sobre la visualización y producción efectiva de gráficos. El énfasis es en el paquete de ggplot2, que está basado en el lenguaje de programación R. Contiene una enorme variedad de representaciones de datos con más de 200 ejemplos. La visualización ayuda a entender lo que pueden comunicar los datos. Además, ayuda a expandir el análisis...
Introduced psittacine birds can become highly invasive. In this study, we assessed invasions of Psittaciformes in Puerto Rico. We reviewed the literature, public databases, citizen science records, and performed in situ population surveys across the island to determine the historical and current status and distribution of psittacine species. We use...
Supplementary Materials S1-S5
S1: Puerto Rico psittacine species checklist and status
S2: Psittacine species occurrence locations and counts
S3: Puerto Rico Landcover classification scheme
S4: Psittacine species sighted by local groups (LGs) in Puerto Rico S5: Distribution of Psittaciformes in Puerto Rico based on location records from Ebird (1960–...
Puerto Rico has experienced multiple introductions of Psittaciformes which have established self-sustaining populations, and the white-winged parakeets (Brotogeris versicolurus) has been considered the most successful invasive psittacine species in the island. In this study, we evaluated their population size, calculated growth rates and estimated...
Historical land use can have long term effects and vegetation recovery of original components may vary. The tropical myco-heterotrophic orchid, Wullschlaegelia calcarata, is known to be sensitive to past disturbance, being most abundant in minimally disturbed forests of Puerto Rico in the West Indies. But spatial patterns of abundance do not necess...
Introduced psittacine birds can become highly invasive. In this study, we assessed invasions of Psittaciformes in Puerto Rico. We reviewed the literature, public databases, citizen science records, and performed in situ population surveys across the island to determine the historical and current status and distribution of psittacine species. We use...
Kreft et al. (2008) presented a global analysis of factors relating to differences in species numbers among 488 island and 970 mainland floras. They tested the relationship between island characteristics (area, isolation, topography, climate and geology) and species richness using traditional and spatial models. They found that area was the stronge...
Premise of research. Tropical epiphytes are susceptible to climatic changes, as evidenced by documented
population declines, range contractions, and range shifts; however, physiological changes in individual plants
may also be indicative of deteriorating climate conditions. Consequently, physiological analyses of tropical
epiphytes whose natural ha...
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 Sou...
The level of invasion (number or proportion of invasive species) in a given area depends on features of the invaded community, propagule pressure, and climate. In this study, we assess the invasive flora of nine islands in the West Indies to identify invasion patterns and evaluate whether invasive species diversity is related to geographical, ecolo...
The original version of the article unfortunately contained an error in Figure 1. The arrow pointing from the native weevil (Stethobaris polita) to the invasive ant (Solenopsis invicta) should be in reverse. Invasive ants attack native weevils, preventing them from feeding on flowers and ovipositing in fruits (see corrected Fig. 1). The caption of...
Non-native species often acquire novel interspecific interactions, which are central to several hypotheses of invasion success, including biotic resistance and invasional meltdown. However, the outcome of these interactions is not often linked with the demographic evidence based on the full life cycle of the species. The Philippine Ground Orchid (S...
Charles Elton proposed that high species diversity and low levels of disturbance provide a measure of biotic resistance against invasions by alien species. While there is some evidence for this hypothesis, there are numerous other factors associated with invasive species richness, and the strength of those relationships is often scale-dependent. Am...
An orchid conservation partnership for southeastern Australia, Proceedings of 6th International Orchid Conservation Congress (IOCC6), 16-20 May 2016, Hong Kong, China, pp. 13. (2016)
Non-native species often acquire novel interspecific interactions, which are central to several hypotheses of invasion success, such as biotic resistance and invasional meltdown. However, the outcome of these interactions is not often linked with the demographic evidence based on the full life cycle of the species. The Philippine Ground Orchid (Spa...
In this paper we describe the phenotypic variation and pollination ecology of the twig orchid epiphyte Rodriguezia granadensis. The species presents flower color polymorphism (pink to white), suggesting that different color forms might be pollinated by different pollinators. To evaluate this hypothesis, one hundred plants were monitored in the fiel...
Movement has broad implications for many areas of biology, including evolution, community and population ecology. Movement is crucial in metapopulation ecology because it facilitates colonization and reduces the likelihood of local extinction via rescue effects. Most metapopulation modeling approaches describe connectivity using pair-wise Euclidean...
Background:
The current live vaccinia virus vaccine used in the prevention of smallpox is contraindicated for millions of immune-compromised individuals. Although vaccination with the current smallpox vaccine produces protective immunity, it might result in mild to serious health complications for some vaccinees. Thus, there is a critical need for...
Background and aims:
Evaluation of population projection matrices (PPMs) that are focused on asymptotically based properties of populations is a commonly used approach to evaluate projected dynamics of managed populations. Recently, a set of tools for evaluating the properties of transient dynamics has been expanded to evaluate PPMs and to conside...
The metapopulation concept is widely established in population biology. It predicts that the likelihood of colonization of an empty patch is positively correlated with its connectivity, because colonizers from occupied patches will be more likely to reach an empty patch if they are closer to it. Another prediction is that the likelihood of extincti...
Predicting population dynamics for rare species is of paramount importance in order to evaluate the likelihood of extinction and planning conservation strategies. However, evaluating and predicting population viability can be hindered from a lack of data. Rare species frequently have small populations, so estimates of vital rates are often very unc...
Aim
The aim of this analysis was to identify strategies that will maximize efficiency and effectiveness in conservation planning. As many orchids are threatened with extinction for various reasons, our primary objective was to combine hotspots analyses with stochastic extinction modelling to highlight possible conservation priorities for Lepanthes...
The distribution of orchids in the epiphytic or lithophytic environment is likely to result from the interactions with other plant species. We tested for associations between bryophyte cover and diversity and the densities of different demographic stages (seedlings and juveniles vs adults) of Lepanthes rupestris (Rock Babyboot Orchid), a riparian t...
Background/Question/Methods
Variation in movement has broad implications for evolutionary biology, community ecology and population dynamics. In metapopulation ecology, movement provides the means to promote the persistence of the metapopulation and local populations over time. Most metapopulation approaches quantify colonization and extinction d...
Lepanthes caritensis is a small epiphytic orchid endemic to Puerto Rico. Although
this species is very rare and demographic studies show that its numbers are declining, it is not protected under the United States Federal Endangered Species Act (ESA). Furthermore, questions remain regarding its distribution, population size and ecological interactio...
Novel markers of fecal pollution in tropical waters are needed since conventional methods recommended for other geographical regions may not apply. To address this, the prevalence of thermotolerant coliforms, enterococci, coliphages, and enterophages was determined by culture methods across a watershed. Additionally, human-, chicken-, and cattle-sp...
ABSTRACT: Lepanthes caritensis is a small epiphytic orchid endemic to Puerto Rico. Although
this species is very rare and demographic studies show that its numbers are declining, it is not protected
under the United States Federal Endangered Species Act (ESA). Furthermore, questions
remain regarding its distribution, population size and ecological...
Premise of the study:
Biotic changes are an inevitable consequence of climate change. Epiphytes may be more susceptible to changes in climate variation, but data regarding responses to climate variability under field conditions are limited. We evaluated whether the abundance of demographic stages in the epiphytic orchid Lepanthes rupestris at the...
Background/Question/Methods
We present the progress and preliminary results of an educational project aim to facilitate eight undergraduate students to develop quantitative analysis (QA) and critical thinking (CT) skills, and to review community and population ecology concepts to learn how to be trained on habitat evaluation (of red-bellied racer...
The ornamental plant-trade is a multi-billion dollar industry, and is a major source for biological invasions. Many exotic plants are known to cause negative economical, ecological, and environmental impacts around the world. Orchids are rarely perceived as invasive species, yet some species are succesful invaders (e.g. Oeceoclades maculata). Among...
Patterns of variation and their fitness consequences are critical in revealing natural selection. One
of the most variable groups of plants are the deception-pollinated orchids, pollinators of which are deceived
in their search for a food reward. Negative frequency-dependent selection and disruptive selection have been
suggested as the means by whi...
Natural selection and genetic drift are the two processes that can lead to cladogenesis. Without a doubt the great diversity and floral adaptation to specific pollinators are likely consequences of natural selection. Detecting natural selection in the wild requires measuring fitness advantage for specific characters. However, few published orchid s...