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Articles 61 - 90 of 107

Full-Text Articles in Evolution

The Association Of Size Variation In The Dental Arch To Third Molar Agenesis For A Modern Population, Devin N. Williams Apr 2018

The Association Of Size Variation In The Dental Arch To Third Molar Agenesis For A Modern Population, Devin N. Williams

USF Tampa Graduate Theses and Dissertations

The frequency with which individuals do not develop their third molars, or wisdom teeth, is increasing worldwide. This current topic of human evolution is relevant to the research of anthropologists, geneticists, dentists, and other researchers involved in the study of human dentition. Many explanations have been offered to account for the prevalence of molar agenesis including, evolutionary, environmental, and genetic theories. The purpose of this research project is to determine the frequency of third molar agenesis and investigate the relationship between third molar agenesis and maxillomandibular jaw dimensions in a sample of orthodontic patients. This research tests the hypotheses that: …


Hip Extensor Mechanics And The Evolution Of Walking And Climbing Capabilities In Humans, Apes, And Fossil Hominins, Elaine E. Kozma, Nicole M. Webb, William Harcourt-Smith, David A. Raichlen, Kristiaan D’Août, Mary H. Brown, Emma M. Finestone, Stephen R. Ross, Peter Aerts, Herman Pontzer Apr 2018

Hip Extensor Mechanics And The Evolution Of Walking And Climbing Capabilities In Humans, Apes, And Fossil Hominins, Elaine E. Kozma, Nicole M. Webb, William Harcourt-Smith, David A. Raichlen, Kristiaan D’Août, Mary H. Brown, Emma M. Finestone, Stephen R. Ross, Peter Aerts, Herman Pontzer

Publications and Research

The evolutionary emergence of humans’ remarkably economical walking gait remains a focus of research and debate, but experi- mentally validated approaches linking locomotor capability to postcranial anatomy are limited. In this study, we integrated 3D morphometrics of hominoid pelvic shape with experimental mea- surements of hip kinematics and kinetics during walking and climbing, hamstring activity, and passive range of hip extension in humans, apes, and other primates to assess arboreal–terrestrial trade-offs in ischium morphology among living taxa. We show that hamstring-powered hip extension during habitual walking and climbing in living apes and humans is strongly predicted, and likely constrained, by …


Selection Perception: Views On The Theory Of Evolution Among Residents Of Moshi, Tanzania, Robin Waterman Apr 2018

Selection Perception: Views On The Theory Of Evolution Among Residents Of Moshi, Tanzania, Robin Waterman

Independent Study Project (ISP) Collection

The theory of evolution is a major tenet of biological science and has many practical applications, particularly in agriculture, medicine, and conservation. Nevertheless, there is significant opposition to the theory and its incorporation into school curricula, largely on religious grounds. This disconnect between public opinion and scientific opinion has been studied at length in the US and to some extent in other industrialized nations, but little is known about the issue in other communities around the world. This paper will use the town of Moshi, Tanzania as a case study in community views and knowledge about the theory of evolution. …


A Model Species For Agricultural Pest Genomics: The Genome Of The Colorado Potato Beetle, Leptinotarsa Decemlineata (Coleoptera: Chrysomelidae), Sean D. Schoville, Yolanda H. Chen, Martin N. Andersson, Joshua B. Benoit, Anita Bhandari, Julia H. Bowsher, Kristian Brevik, Kaat Cappelle, Mei-Ju M. Chen, Anna K. Childers, Christopher Childers, Olivier Christiaens, Justin Clements, Elise M. Didion, Elena N. Elpidina, Patamarerk Engsontia, Markus Friedrich, Inmaculada García-Robles, Richard A. Gibbs, Chandan Goswami, Alessandro Grapputo, Kristina Gruden, Marcin Grynberg, Bernard Henrissat, Emily C. Jennings, Jeffery W. Jones, Megha Kalsi, Sher A. Khan, Abhishek Kumar, Fei Li, Vincent Lombard, Subba Reddy Palli, June-Sun Yoon Jan 2018

A Model Species For Agricultural Pest Genomics: The Genome Of The Colorado Potato Beetle, Leptinotarsa Decemlineata (Coleoptera: Chrysomelidae), Sean D. Schoville, Yolanda H. Chen, Martin N. Andersson, Joshua B. Benoit, Anita Bhandari, Julia H. Bowsher, Kristian Brevik, Kaat Cappelle, Mei-Ju M. Chen, Anna K. Childers, Christopher Childers, Olivier Christiaens, Justin Clements, Elise M. Didion, Elena N. Elpidina, Patamarerk Engsontia, Markus Friedrich, Inmaculada García-Robles, Richard A. Gibbs, Chandan Goswami, Alessandro Grapputo, Kristina Gruden, Marcin Grynberg, Bernard Henrissat, Emily C. Jennings, Jeffery W. Jones, Megha Kalsi, Sher A. Khan, Abhishek Kumar, Fei Li, Vincent Lombard, Subba Reddy Palli, June-Sun Yoon

Entomology Faculty Publications

The Colorado potato beetle is one of the most challenging agricultural pests to manage. It has shown a spectacular ability to adapt to a variety of solanaceaeous plants and variable climates during its global invasion, and, notably, to rapidly evolve insecticide resistance. To examine evidence of rapid evolutionary change, and to understand the genetic basis of herbivory and insecticide resistance, we tested for structural and functional genomic changes relative to other arthropod species using genome sequencing, transcriptomics, and community annotation. Two factors that might facilitate rapid evolutionary change include transposable elements, which comprise at least 17% of the genome and …


Audiobook Of A World From Dust, Ben Mcfarland Jan 2018

Audiobook Of A World From Dust, Ben Mcfarland

Faculty Open Access Books

A World From Dust is a popular science book about the chemical sequence behind the evolution of creation.

It’s about how geology, biology, and chemistry worked together over billions of years, providing a hidden order under the random flow of genes and lava and water.

It’s about the chemical job that each element takes up in life, and how that job is predictable from its place on the periodic table.

It can be told as the story of many elements: how iron and sulfur gave a spark of life; how manganese was a key for oxygen; and how copper and …


Generating Species Assemblages For Restoration And Experimentation: A New Method That Can Simultaneously Converge On Average Trait Values And Maximize Functional Diversity, David C. Laughlin, Loïc Chalmandrier, Chaitanya Joshi, Michael Renton, John M. Dwyer, Jennifer L. Funk Jan 2018

Generating Species Assemblages For Restoration And Experimentation: A New Method That Can Simultaneously Converge On Average Trait Values And Maximize Functional Diversity, David C. Laughlin, Loïc Chalmandrier, Chaitanya Joshi, Michael Renton, John M. Dwyer, Jennifer L. Funk

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

1.Restoring resilient ecosystems in an era of rapid environmental change requires a flexible framework for selecting assemblages of species based on functional traits. However, current trait‐based models have been limited to algorithms that select species assemblages that only converge on specified average trait values, and could not accommodate the common desire among restoration ecologists to generate functionally diverse assemblages.

2.We have solved this problem by applying a nonlinear optimization algorithm to solve for the species relative abundances that maximize Rao's quadratic entropy (Q) subject to other linear constraints. Rao's Q is a closed‐form algebraic expression of functional diversity …


Emerging Infectious Disease And The Imperiled Relict Leopard Frog, Anthony Wayne Waddle Dec 2017

Emerging Infectious Disease And The Imperiled Relict Leopard Frog, Anthony Wayne Waddle

UNLV Theses, Dissertations, Professional Papers, and Capstones

The disease chytridiomycosis, caused by the aquatic fungal pathogen Batrachochytrium dendrobatidis (Bd), has emerged as a major contributing factor for worldwide amphibian declines. Although relatively recently described, the impacts from the disease this pathogen causes have been definitively tied to amphibian declines, including some that occurred decades ago. In some cases, declines of individual species occurred with little documentation and are thus poorly understood. The relict leopard frog (Rana onca = Lithobates onca) has experienced such a decline and by the latter part of the 20th century only occurred in two general areas in southern Nevada. Recent research has found …


Handicap Principle Implies Emergence Of Dimorphic Ornaments, Sara Clifton, Daniel M. Abrams, Rosemary I. Braun Oct 2017

Handicap Principle Implies Emergence Of Dimorphic Ornaments, Sara Clifton, Daniel M. Abrams, Rosemary I. Braun

Annual Symposium on Biomathematics and Ecology Education and Research

No abstract provided.


The Effects Of Evolution On Food Web Diversity And Abundance, Rosalyn Rael Oct 2017

The Effects Of Evolution On Food Web Diversity And Abundance, Rosalyn Rael

Annual Symposium on Biomathematics and Ecology Education and Research

No abstract provided.


Software Development For Genome Sequence Analysis, David Farr May 2017

Software Development For Genome Sequence Analysis, David Farr

Symposium Of University Research and Creative Expression (SOURCE)

The cost of genome sequencing has decreased rapidly, expanding availability for many biological applications (Muir 2016). For example, researchers can now obtain genome sequences from multiple populations under different types of selection. Comparison of these sequences allows for identification of chromosome regions and specific genes associated with adaptive evolution (Kelly 2013). As an increasing number of researchers engage in this type of inquiry, many have created in-house computer scripts to analyze the raw sequence data (e.g., Kelly 2013), creating a gap in both continuity and standardization.

Using a test dataset and preliminary results from an ongoing artificial selection experiment in …


Hexarray: A Novel Self-Reconfigurable Hardware System, Fady Hussein May 2017

Hexarray: A Novel Self-Reconfigurable Hardware System, Fady Hussein

Boise State University Theses and Dissertations

Evolvable hardware (EHW) is a powerful autonomous system for adapting and finding solutions within a changing environment. EHW consists of two main components: a reconfigurable hardware core and an evolutionary algorithm. The majority of prior research focuses on improving either the reconfigurable hardware or the evolutionary algorithm in place, but not both. Thus, current implementations suffer from being application oriented and having slow reconfiguration times, low efficiencies, and less routing flexibility. In this work, a novel evolvable hardware platform is proposed that combines a novel reconfigurable hardware core and a novel evolutionary algorithm.

The proposed reconfigurable hardware core is a …


Cranial Morphological Distinctiveness Between Ursus Arctos And U. Americanus, Benjamin James Hillesheim May 2017

Cranial Morphological Distinctiveness Between Ursus Arctos And U. Americanus, Benjamin James Hillesheim

Electronic Theses and Dissertations

Despite being separated by millions of years of evolution, black bears (Ursus americanus) and brown bears (Ursus arctos) can be difficult to distinguish based on skeletal and dental material alone. Complicating matters, some Late Pleistocene U. americanus are significantly larger in size than their modern relatives, obscuring the identification of the two bears. In the past, fossil bears have been identified based on differences in dental morphology or size. This study used geometric morphometrics to look at overall differences in cranial shape and used step-wise discriminant analysis to identify specific characters that distinguish cranial morphology between …


Integrating The Field Of Prebiotic Chemistry Into A Christian Worldview, Matthew B. Anderson Apr 2017

Integrating The Field Of Prebiotic Chemistry Into A Christian Worldview, Matthew B. Anderson

Senior Honors Theses

This thesis will provide an overarching examination into the scientific field of prebiotic chemistry, the purported chemistry of the formation of life on earth. Prebiotic chemistry is a critical area of science particularly for Christian scientists to study since it is used by many evolutionists as evidence for the evolution of life, rather than the formation by an intelligent designer. Extensive literature-based research from previously published articles will be conducted on the formation of biologically necessary molecules, including amino acids. Primary focus will be placed on the formation of amino acids in a primordial earth environment, first demonstrated by the …


Five Species Of Fossil Equids Preserved In-Situ At Ashfall Fossil Beds, Rick E. Otto Jan 2017

Five Species Of Fossil Equids Preserved In-Situ At Ashfall Fossil Beds, Rick E. Otto

University of Nebraska State Museum: Programs Information

Fully articulated, three-dimensionally preserved skeletons from five species of fossil Equids are now represented, and preserved in-situat the Ashfall Fossil Beds in northcentral Nebraska. The site is well known for dozens of barrel-bodied rhino (Teleoceras major) skeletons. A diversity of horse species that inhabited Nebraska during the late Miocene Epoch have been exposed in the fossil bed. Genera include Cormohipparion, Neohipparon, Pliohippus, Protohippus, and Pseudhipparion. An exceptionally well-preserved skeleton of the small-sized, three-toed species Pseudhipparion gratumwas recently exposed, and is on display only a few feet from where visitors stand.


Evolution In The Deep Sea: Scales And Mechanisms Of Population Divergence, Amanda E. Glazier Dec 2016

Evolution In The Deep Sea: Scales And Mechanisms Of Population Divergence, Amanda E. Glazier

Graduate Doctoral Dissertations

The deep sea is the Earth’s largest ecosystem and harbors a unique and largely endemic fauna. Although most research has focused on the ecological mechanisms that allow coexistence, recent studies have begun to investigate how this remarkable fauna evolved.. My work quantifies geographic patterns of genetic variation and investigates potential mechanisms that shape evolution in the deep ocean.

Bathymetric genetic divergence is common in the deep sea with population structure typically decreasing with depth. The evolutionary mechanisms that underlie these patterns are poorly understood. Geographic patterns of genetic variation indicated that the protobranch bivalve Neilonella salicensis was composed of two …


Bounds On The Expected Size Of The Maximum Agreement Subtree, Colby Long, Daniel Irving Bernstein, Lam Si Tung Ho, Mike Steel, Katherine St. John, Seth Sullivant Oct 2016

Bounds On The Expected Size Of The Maximum Agreement Subtree, Colby Long, Daniel Irving Bernstein, Lam Si Tung Ho, Mike Steel, Katherine St. John, Seth Sullivant

Annual Symposium on Biomathematics and Ecology Education and Research

No abstract provided.


General Equations For Natural Selection Under Complete Dominance, Kasthuri Kannan, Adriana Heguy Oct 2016

General Equations For Natural Selection Under Complete Dominance, Kasthuri Kannan, Adriana Heguy

Annual Symposium on Biomathematics and Ecology Education and Research

No abstract provided.


Analysis Of The Intricacies Of Substrate Recognition Of High Mobility Group Proteins And Aminoacyl-Trna Synthetases Using Non-Cognate Substrates, Douglas Van Iverson Ii Aug 2016

Analysis Of The Intricacies Of Substrate Recognition Of High Mobility Group Proteins And Aminoacyl-Trna Synthetases Using Non-Cognate Substrates, Douglas Van Iverson Ii

Dissertations

The studies presented in section 1 (Chapters I-IV) focus on the design and development of nucleic acid four-way junctions (4WJs) to target a member of the high mobility group (HMG) proteins, the proinflammatory cytokine high mobility group box 1 protein (HMGB1). In the present study, hybrid PNA-DNA 4WJs based on a model DNA 4WJ were constructed to improve the thermal stability of 4WJs while maintaining strong binding affinity toward HMGB1. An electrophoretic mobility shift assay (EMSA) was used to examine the binding affinity of an isolated DNA binding domain of HMGB1, the HMGB1 b-box (HMGB1b), toward a set of PNA-DNA …


Revelation Of Yin-Yang Balance In Microbial Cell Factories By Data Mining, Flux Modeling, And Metabolic Engineering, Gang Wu May 2016

Revelation Of Yin-Yang Balance In Microbial Cell Factories By Data Mining, Flux Modeling, And Metabolic Engineering, Gang Wu

McKelvey School of Engineering Graduate Student Theses & Dissertations

The long-held assumption of never-ending rapid growth in biotechnology and especially in synthetic biology has been recently questioned, due to lack of substantial return of investment. One of the main reasons for failures in synthetic biology and metabolic engineering is the metabolic burdens that result in resource losses. Metabolic burden is defined as the portion of a host cells resources either energy molecules (e.g., NADH, NADPH and ATP) or carbon building blocks (e.g., amino acids) that is used to maintain the engineered components (e.g., pathways). As a result, the effectiveness of synthetic biology tools heavily dependents on cell capability to …


The End-Cretaceous Mass Extinction And The Deccan Traps Eruptions, Rebecca Teed May 2016

The End-Cretaceous Mass Extinction And The Deccan Traps Eruptions, Rebecca Teed

Earth and Environmental Sciences Faculty Publications

This handout focuses on the evidence for the theory that a series of flood-basalt eruptions in northern India caused the mass extinction at the end of the Cretaceous Period. The dinosaurs and about 75% of all marine invertebrate species and many other organisms died abruptly at this time. This is one of a set of four articles on possible causes of the Permian and Cretaceous mass extinctions that can be used to organize classroom debates or to have students compare and contrast the events and their causes.


The End-Cretaceous Mass Extinction And The Chicxulub Impact, Rebecca Teed May 2016

The End-Cretaceous Mass Extinction And The Chicxulub Impact, Rebecca Teed

Earth and Environmental Sciences Faculty Publications

This handout focuses on the evidence for the theory that a massive meteor impact off the coast of Mexico caused the mass extinction at the end of the Cretaceous Period. The dinosaurs and about 75% of all marine invertebrate species and many other organisms died abruptly at this time. It is part of a set of four articles on possible causes of the Permian and Cretaceous mass extinctions that can be used to organize classroom debates or to have students compare and contrast the events and their causes.


The End-Permian Mass Extinction And A Possible Massive Impact, Rebecca Teed May 2016

The End-Permian Mass Extinction And A Possible Massive Impact, Rebecca Teed

Earth and Environmental Sciences Faculty Publications

This handout examines the evidence for the theory that a massive meteor impact caused the mass extinction at the end of the Permian Period. This is the worst mass extinction known to geologists, and 90% or more of all species on Earth were wiped out. It is part of a set of four articles on possible causes of the Permian and Cretaceous mass extinctions that can be used to organize classroom debates or to have students compare and contrast the events and their causes.


The End-Permian Mass Extinction And The Siberian Traps Eruptions, Rebecca Teed May 2016

The End-Permian Mass Extinction And The Siberian Traps Eruptions, Rebecca Teed

Earth and Environmental Sciences Faculty Publications

This handout focuses on the evidence for the theory that a series of flood-basalt eruptions in Siberia caused the mass extinction at the end of the Permian Period. This is the worst mass extinction known to geologists, and 90% or more of all species on Earth were wiped out. It is part of a set of four articles on possible causes of the Permian and Cretaceous mass extinctions that can be used to organize classroom debates or to have students compare and contrast the events and their causes.


Resolving Gnetum Evolutionary History, Angela Mcfadden Jan 2016

Resolving Gnetum Evolutionary History, Angela Mcfadden

All Master's Theses

Gnetum are non-flowering seed plants of the tropics, indigenous to South America, Africa, and Asia. This group of about 40 species is fascinating to botanists because it shares distinctive morphological characteristics with flowering plants, such as broad leaves, woody stems, and flower-like strobili. There are still questions surrounding the relationships within the genus of Gnetum. With that in mind, I focused my work on generating phylogenetic hypotheses, using two molecular data sets: a concatenation of over 60 different chloroplast genes (66,815 base pairs), and the whole chloroplast genome (128,772 base pairs). This allowed me to compare the two phylogenies …


Ecology And Morphology Of The Late Miocene Musk Deer, Longirostromeryx Wellsi (Artiodactyla: Moschidae: Blastomerycinae), Katheryn Y. C. Chen Aug 2015

Ecology And Morphology Of The Late Miocene Musk Deer, Longirostromeryx Wellsi (Artiodactyla: Moschidae: Blastomerycinae), Katheryn Y. C. Chen

Department of Earth and Atmospheric Sciences: Dissertations, Theses, and Student Research

Longirostromeryx wellsi, one of the latest surviving members of the extinct clade Blastomerycinae (Artiodactyla: Moschidae), possesses highly derived craniodental morphology that deviates from typical musk deer form. Previous work suggests that the unique anatomy of L. wellsi represents adaptations for occupying open savannas. To test this hypothesis I conduct principal components analysis on five postcranial bones of L. wellsi, comparing them to that of several extant ruminant artiodactyls, which are divided among seven habitat categories. These elements are also compared with the postcrania of other blastomerycines. These analyses indicate that L. wellsi anatomy is most similar to that of other …


Speed And Resolution In The Age Of Technological Reproducibility, Shawn Taylor Jan 2015

Speed And Resolution In The Age Of Technological Reproducibility, Shawn Taylor

Theses and Dissertations

The rate of acceleration of the biologic and synthetic world has for a while now, been in the process of exponentially speeding up, maxing out servers and landfills, merging with each other, destroying each other. The last prehistoric relics on Earth are absorbing the same oxygen, carbon dioxide and electronic waves in our biosphere as us. A degraded .jpeg enlarged to full screen on a Samsung 4K UHD HU8550 Series Smart TV - 85” Class (84.5” diag.). Within this composite ecology, the ancient limestone of the grand canyon competes with the iMax movie of itself, the production of Mac pros, …


The Evolution Of Respiratory O2/No Reductases: An Out-Of-The-Phylogenetic-Box Perspective, Anne-Lise Ducluzeau, Barbara Schoepp-Cothenet, Robert Van Lis, Frauke Baymann, Michael J. Russell, Wilfgang Nitschke Jun 2014

The Evolution Of Respiratory O2/No Reductases: An Out-Of-The-Phylogenetic-Box Perspective, Anne-Lise Ducluzeau, Barbara Schoepp-Cothenet, Robert Van Lis, Frauke Baymann, Michael J. Russell, Wilfgang Nitschke

Department of Biochemistry: Faculty Publications

Complex life on our planet crucially depends on strong redox disequilibria afforded by the almost ubiquitous presence of highly oxidizing molecular oxygen. However, the history of O2-levels in the atmosphere is complex and prior to the Great Oxidation Event some 2.3 billion years ago, the amount of O2 in the biosphere is considered to have been extremely low as compared with present-day values. Therefore the evolutionary histories of life and of O2-levels are likely intricately intertwined. The obvious biological proxy for inferring the impact of changing O2-levels on life is the evolutionary history …


Inter-And Intra-Population Variability Across The Transcriptome Of Lake Baikal’S Endemic Copepod With Ramifications For Adapting To Climate Change, Larry L. Bowman Jr May 2014

Inter-And Intra-Population Variability Across The Transcriptome Of Lake Baikal’S Endemic Copepod With Ramifications For Adapting To Climate Change, Larry L. Bowman Jr

Electronic Theses and Dissertations

The future of Lake Baikal’s biodiversity is uncertain in response to climate change. Unlike its diverse benthos, Lake Baikal’s zooplankton is species poor, with up to 96% of its biomass being composed of a single Calanoid copepod species, Epischura baikalensis. This study characterizes the genetic differentiation and differential gene expression of E. baikalensis. Using partial-transcriptome sequences obtained by 454 Rosche and Illumina sequencing technologies, the genetic differentiation at inferred single nucleotide polymorphism (SNP) sites and differential gene expression in populations sampled from various parts of the lake were analyzed. The functional genomics of genes showed significant differential …


Body Size And Species Richness Changes In Glyptosaurinae (Squamata: Anguidae) Through Climatic Transitions Of The North American Cenozoic, Sara Elshafie Apr 2014

Body Size And Species Richness Changes In Glyptosaurinae (Squamata: Anguidae) Through Climatic Transitions Of The North American Cenozoic, Sara Elshafie

Department of Earth and Atmospheric Sciences: Dissertations, Theses, and Student Research

Poikilothermic vertebrates offer excellent climate proxies based on relationships between environment and measurable variables such as body size and species richness. Relationships of these variables in lizards to environmental transitions over long time scales are poorly understood. Here I show that patterns of body size and species richness in a lizard clade, Glyptosaurinae (Squamata: Anguidae), correspond to known histories of paleotemperatures through the Cenozoic of North America. Glyptosaurines have the richest fossil record among North American Cenozoic lizards and exhibit a wide range of skull sizes. In order to estimate body size for glyptosaurines and other fossil anguids, I collected …


Fossil Crocodilians From The High Guajira Peninsula Of Colombia, And The History Of Neogene Crocodilian Diversity In Tropical South America, Jorge W. Moreno-Bernal Apr 2014

Fossil Crocodilians From The High Guajira Peninsula Of Colombia, And The History Of Neogene Crocodilian Diversity In Tropical South America, Jorge W. Moreno-Bernal

Department of Earth and Atmospheric Sciences: Dissertations, Theses, and Student Research

The greatest diversity of Cenozoic crocodilians occurred during the Miocene in equatorial South America. However, the origin of this high diversity and its relationship to environmental factors are poorly understood. Most described species come from localities assigned to Laventan (13.8-11.8 Ma) and Huayquerian (9.0-6.8 Ma) South American land mammal ages (SALMAS), whereas the record is sparse in the early to middle Miocene and after the latest Miocene and Pliocene. Field research in the Castilletes (early Miocene-Pliocene) Formation in the High Guajira Peninsula of Colombia provides new fossil data on the origin of Neotropical crocodylian diversity. The Castilletes Formation crops out …