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The Functional Morphology of Shark Control Surfaces: A Comparative Analysis
Title
The Functional Morphology of Shark Control Surfaces: A Comparative Analysis.
Creator
Hoffmann, Sarah Louise, Porter, Marianne E., Florida Atlantic University, Charles E. Schmidt College of Science, Department of Biological Sciences
Abstract/Description
Sharks are an objectively diverse group of animals; ranging in maximum size from 2,000cm (whale shark) to 17cm (dwarf lantern shark); occupying habitats that are periodically terrestrial (epaulette shark) to the deepest parts of the ocean (frilled shark); relying on a diversity of diets from plankton to marine mammals; with vast amounts of morphology diversity such as the laterally expanded heads of hammerhead species, the elongate caudal fins of thresher species, and the tooth embedded...
Show moreSharks are an objectively diverse group of animals; ranging in maximum size from 2,000cm (whale shark) to 17cm (dwarf lantern shark); occupying habitats that are periodically terrestrial (epaulette shark) to the deepest parts of the ocean (frilled shark); relying on a diversity of diets from plankton to marine mammals; with vast amounts of morphology diversity such as the laterally expanded heads of hammerhead species, the elongate caudal fins of thresher species, and the tooth embedded rostrum of saw shark species representing some of the anatomical extremes. Yet despite these obvious differences in morphology, physiology, and ecology, the challenges associated with studying hard to access, large bodied, pelagic animals have limited our comparative understanding of form and function as it relates to swimming within this group. The majority of shark swimming studies examine species that succeed in captivity, which are usually benthic associated sharks that spend time resting on the substrate. These studies have also been limited by the use of flumes, in which the unidirectional flow and small working area precludes the analysis of larger animals, volitional swimming, and maneuvering. The few existing volitional kinematics studies on sharks quantify two-dimensional kinematics which are unable to capture movements not observable in the plane of reference. With this study, we quantified the volitional swimming kinematics of sharks in relation to morphological, physiological, and ecological variation among species. We developed a technique to analyze three-dimensional (3D) kinematics in a semi-natural, large volume environment, which, to our knowledge, provides the first3D analysis of volitional maneuvering in sharks. We demonstrated that Pacific spiny dogfish and bonnethead sharks rotate the pectoral fins substantially during yaw (horizontal) maneuvering and is correlated with turning performance. We proposed that ecomorphological differences correlate with the varied maneuvering strategies we observed between the two species. We also found that there is some mechanical constraint on shark pectoral fin shape that is explained by phylogenetic relationships but describe a continuum of morphological variables within that range. We propose standardized terminology and methodology for the future assessment of shark pectoral fin morphology and function. As with previous studies, the ease of access to species was a challenge in this study and future studies should continue to assess the functional ecomorphology of shark pectoral fins among species.
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Date Issued
2019
PURL
http://purl.flvc.org/fau/fd/FA00013217
Subject Headings
Sharks, Morphology (Animals), Kinematics
Format
Document (PDF)
Assessment of Sexual Dimorphism on the First and Second Ribs: Exploring Geometric Morphometrics
Title
Assessment of Sexual Dimorphism on the First and Second Ribs: Exploring Geometric Morphometrics.
Creator
Bhramdat, Henna D., Brown, Clifford T., Florida Atlantic University, Dorothy F. Schmidt College of Arts and Letters, Department of Anthropology
Abstract/Description
Estimating the sex of unknown human skeletal remains is important to the fields of forensic anthropology, bioarchaeology, and other specialties. I studied sexual dimorphism on the first and second ribs to estimate sex from skeletal remains. I employed two approaches. I used geometric morphometrics to analyze landmark and semilandmark coordinate points to examine the overall shape of the ribs. I also examined the sternal end of the ribs for size using the superior-inferior height (SIH) and...
Show moreEstimating the sex of unknown human skeletal remains is important to the fields of forensic anthropology, bioarchaeology, and other specialties. I studied sexual dimorphism on the first and second ribs to estimate sex from skeletal remains. I employed two approaches. I used geometric morphometrics to analyze landmark and semilandmark coordinate points to examine the overall shape of the ribs. I also examined the sternal end of the ribs for size using the superior-inferior height (SIH) and anteriorposterior breadth (APB) in a binary logistic regression (BLR) model. Differences in male and female first and second ribs are undetectable when landmark coordinate points are used to capture shape variability, but significant differences in the shape of the ribs, however, are detected through the use of semilandmark coordinate points. Using semilandmark points to estimate sex presented an accuracy rate of 80.7% from the first rib, and 72.9% from the second rib. The use of the sternal end presents consistent results in its ability to estimate sex with an accuracy rate of 84.2%. The BLR model reveals significant differences between males and females than the geometric morphometric approach; it is more applicable for discerning sexual dimorphism of unknown individuals. This study reveals that while geometric morphometrics provides a powerful approach to assessing morphological differences, it is not always better than simpler methods, in this case, simple measurements analyzed through BLR.
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Date Issued
2018
PURL
http://purl.flvc.org/fau/fd/FA00005976
Subject Headings
Sexual dimorphism (Animals), Ribs, Morphology
Format
Document (PDF)
Functional morphology ofspermatophores and sperm transfer in calanoid copepods
Title
Functional morphology ofspermatophores and sperm transfer in calanoid copepods.
Creator
Blades-Eckelbarger, Pamela I., Harbor Branch Oceanographic Institute
Date Issued
1991
PURL
http://purl.flvc.org/fau/fd/FA00007445
Subject Headings
Calanoida, Copepoda--Reproduction, Spermatophores, Morphology (Animals)
Format
Document (PDF)
Developmental Morphology of Flippers in Sea Turtles and Penguins
Title
Developmental Morphology of Flippers in Sea Turtles and Penguins.
Creator
Kwong, Grace W., Wyneken, Jeanette, Florida Atlantic University, Charles E. Schmidt College of Science, Department of Biological Sciences
Abstract/Description
There are no modem anatomical studies of flipper development or particularly any examining limb formation across distantly related taxa converging on similar flipper morphology. This study compares and contrasts the development of flippers in sea turtle (Caretta caretta) and penguin (Spheniscus demersus , Eudyptula minor) embryos. Embryos were fixed, cleared and stained for cartilage anlagen, and prepared as whole mounts. Skeletal elements forming the flipper and changes in their growth rates...
Show moreThere are no modem anatomical studies of flipper development or particularly any examining limb formation across distantly related taxa converging on similar flipper morphology. This study compares and contrasts the development of flippers in sea turtle (Caretta caretta) and penguin (Spheniscus demersus , Eudyptula minor) embryos. Embryos were fixed, cleared and stained for cartilage anlagen, and prepared as whole mounts. Skeletal elements forming the flipper and changes in their growth rates were described across developmental stages. Results suggest skeletal elements contribute differently to sea turtle and penguin flipper blades and there are significant differences in bone shape and growth patterns. Greater proportional increases in lengths and areas were found in sea turtles elements compared to penguins. Sea turtles appear to depend on a pathway resulting in elongation of distal elements to build a flipper, whereas penguin limbs undergo flattening and expansion of fewer elements to meet a similar structural goal.
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Date Issued
2006
PURL
http://purl.flvc.org/fau/fd/FA00000784
Subject Headings
Sea turtles--Physiology, Sea turtles--Morphology, Penguins--Morphology, Animal locomotion, Marine ecology
Format
Document (PDF)
Aspects of internalanatomy and reproduction in the copepoda
Title
Aspects of internalanatomy and reproduction in the copepoda.
Creator
Blades-Eckelbarger, Pamela I., Harbor Branch Oceanographic Institute
Date Issued
1986
PURL
http://purl.flvc.org/fau/fd/FA00007293
Subject Headings
Copepoda--Reproduction, Copepoda--Anatomy, Morphology (Animals), Calanoida
Format
Document (PDF)
Polypide morphology and feeding behavior in marine ectoprocts
Title
Polypide morphology and feeding behavior in marine ectoprocts.
Creator
Winston, Judith E., Harbor Branch Oceanographic Institute
Date Issued
1978
PURL
http://purl.flvc.org/FCLA/DT/3174433
Subject Headings
Bryozoa, Animal feeding, Morphology, Senses and sensation, Water currents
Format
Document (PDF)
Reevaluation of stalked aplysinid sponges, with description of a new species from the upper Bahamian slope
Title
Reevaluation of stalked aplysinid sponges, with description of a new species from the upper Bahamian slope.
Creator
Maldonado, Manuel, Young, Craig M., Harbor Branch Oceanographic Institute
Date Issued
1998
PURL
http://purl.flvc.org/FCLA/DT/3171650
Subject Headings
Sponges, Sponges --Bahamas, Sponges --Anatomy, Morphology (Animals), Oceanographic submersibles
Format
Document (PDF)
Halimeda pygmaea and Halimeda pumila (Bryopsidales, Chlorophyta): two new dwarf species from fore reef slopes in Fiji and the Bahamas
Title
Halimeda pygmaea and Halimeda pumila (Bryopsidales, Chlorophyta): two new dwarf species from fore reef slopes in Fiji and the Bahamas.
Creator
Verbruggen, Heroen, Littler, Diane S., Littler, Mark M., Harbor Branch Oceanographic Institute
Date Issued
2007
PURL
http://purl.flvc.org/FCLA/DT/3174425
Subject Headings
Halimeda, Phylogeny --Molecular aspects, Animals --Classification, Caulerpales, Morphology
Format
Document (PDF)
comparison of stability in swimming loggerhead (Caretta caretta) and green (Chelonia mydas) sea turtle posthatchlings
Title
A comparison of stability in swimming loggerhead (Caretta caretta) and green (Chelonia mydas) sea turtle posthatchlings.
Creator
Dougherty, Erin., Charles E. Schmidt College of Science, Department of Biological Sciences
Abstract/Description
Posthatchling green (Chelonia mydas) and loggerhead (Caretta caretta) turtles overlap ecologically but differ morphologically. This study compared hydrodynamic stability between the two species during swimming to test for functional differences in body shape. Flipper movement paths, four stability measures (yaw, pitch, heave, and sideslip), and the relative positions of the centers of buoyancy and gravity were compared between species. Both centers of buoyancy and gravity lie in the anterior...
Show morePosthatchling green (Chelonia mydas) and loggerhead (Caretta caretta) turtles overlap ecologically but differ morphologically. This study compared hydrodynamic stability between the two species during swimming to test for functional differences in body shape. Flipper movement paths, four stability measures (yaw, pitch, heave, and sideslip), and the relative positions of the centers of buoyancy and gravity were compared between species. Both centers of buoyancy and gravity lie in the anterior body; their positions relative to one another differed with species, but showed no functional consequences. Neither species demonstrated substantial yaw, sideslip, or pitch. Both experienced upward heave with the flippers' downstroke and downward heave with the upstroke; however phase relationships differed between these limb and body motions. No differences were found between the two species. Despite obvious morphological differences, loggerheads and green turtles were similarly stable during swimming, suggesting that the species use different mechanisms to achieve stability.
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Date Issued
2009
PURL
http://purl.flvc.org/FAU/186689
Subject Headings
Sea turtles, Morphology, Sea turtles, Physiology, Animal locomotion, Marine ecology
Format
Document (PDF)
Ecomorphology of Shark Electroreceptors
Title
Ecomorphology of Shark Electroreceptors.
Creator
Cornett, Anthony D., Kajiura, Stephen M., Florida Atlantic University
Abstract/Description
Sharks possess an electrosensory system which allows the detection of electric fields . How this system varies among related taxa and among species inhabiting different environments remains unexplored. Electroreceptor number was quantified for representative species of related taxa (genera, families, orders) from different environments (pelagic, coastal, deepwater) and taxa from similar environments to determine potential phylogenetic constraint or evolutionary convergence. Coastal open water...
Show moreSharks possess an electrosensory system which allows the detection of electric fields . How this system varies among related taxa and among species inhabiting different environments remains unexplored. Electroreceptor number was quantified for representative species of related taxa (genera, families, orders) from different environments (pelagic, coastal, deepwater) and taxa from similar environments to determine potential phylogenetic constraint or evolutionary convergence. Coastal open water sharks possess the greatest number of electroreceptors; deepwater sharks the least. Pelagic and coastal benthic sharks retain comparable electrosensory pore numbers despite inhabiting vastly different environments. Electrosensory pores were primarily located in ventral distributions, except among coastal open water sharks which possess roughly even distributions around the head. Among related species and genera, pore numbers and distribution are comparable, with greater variation among higher taxa. Results implicate evolutionary convergence as the primary influence in electroreceptor development, while phylogenetic constraint establishes similar base values for number and distribution.
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Date Issued
2006
PURL
http://purl.flvc.org/fau/fd/FA00000737
Subject Headings
Sharks--Ecology, Sharks--Morphology, Echolocation (Physiology), Aquatic animals--Physiology, Senses and sensation, Adaptation (Biology)
Format
Document (PDF)