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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

BEHAVIORAL MANIFESTATIONS OF PHOTOSENSITIVITY IN CERCARIAE OF SCHISTOSOMA MANSONI (DIGENEA: SCHISTOSOMATIDAE)

Unknown Date (has links)
Source: Dissertation Abstracts International, Volume: 40-07, Section: B, page: 3045. / Thesis (Ph.D.)--The Florida State University, 1979.
2

PREDATORY BEHAVIOR OF EASTERN DIAMONDBACK RATTLESNAKES (CROTALUS ADAMANTEUS): FIELD ENCLOSURE AND Y-MAZE LABORATORY STUDIES, EMPHASIZING PREY TRAILING BEHAVIORS

Unknown Date (has links)
Source: Dissertation Abstracts International, Volume: 41-07, Section: B, page: 2510. / Thesis (Ph.D.)--The Florida State University, 1980.
3

THE REPRODUCTIVE ANATOMY, SEASONAL CYCLES, AND DEVELOPMENT OF THE ATLANTIC STINGRAY, DASYATIS SABINA (LESUEUR) (PISCES, DASYATIDAE) FROM THE NORTHEASTERN GULF OF MEXICO

Unknown Date (has links)
Adult and juvenile specimens of Dasyatis sabina were collected throughout 1976 and 1977. Embryos were collected from gestating females in both years. Representative specimens were examined for gross and histological anatomy and seasonal change. Females became sexually mature between 225 and 240 mm DW; males, between 205 and 215 mm DW. Anatomically, the reproductive systems of D. sabina appeared to be typical in most respects to other myliobatoids. Seasonally, males underwent a distinct annual cycle. Spermatogenesis followed typical elasmobranch patterns and served as a marker for the cycle which consisted of five phases, latent (May to August), early spermatogenesis (August to November), mid-spermatogenesis (September to February), late spermatogenesis (February to April), and pre-latent (April to May). Males contained ripe sperm in their seminal vesicles from September to May. Females also exhibited a yearly cycle. Though oocytes continually developed over the entire year, most underwent atresia. However, each year one group began to enlarge in the summer and continued to develop to maturation in April. Mating occurred at least twice (Fall and Spring) and sperm cells were observed in association with the uterine lining in a manner that suggested sperm storage from October to April. Ovulation and fertilization occurred in April and gestation continued to July or August. During the later stages of fetal development the uterine lining of the mother underwent dramatic changes associated with the secretion of an histotroph. Birth occurred when fetuses were between 100 and 135 mm DW. Brood size ranged from one to four but most females contained two fetuses. / Source: Dissertation Abstracts International, Volume: 43-03, Section: B, page: 0650. / Thesis (Ph.D.)--The Florida State University, 1982.
4

SIZE AND SHAPE IN THE BARNACLE GENUS BALANUS

Unknown Date (has links)
Influence of size upon shell shape and various other aspects of the body plan of the genus Balanus was investigated using linear and volumetric measurements collected from 232 adult individuals of 14 species representing variation in size, shell form and shell design thought to occur in the genus. Statistical techniques applied included Least-Squares regression, multiple step-wise regression, principal components analysis (PCA), analysis of variance (ANOVA) and analysis of covariance (ANCOVA). / Four of 15 morphometric variables examined are satisfactory estimators of individual size (total weight): valve weight, soma weight, total shell volume and basal length; the last two being generally preferred. / While shell form among species is superficially similar, no two species are, in fact, identical; neither do they scale alike. Intraspecific variation for five ratio variables shows strong allometry over the adult size range of each species. As size increases, there is a trend for the basis and orifice to maintain their shapes or to become slghtly more elliptical and for shells to become more conical and relatively taller. / Throughout their size ranges, species can be described by these geometries: paraboloid (6 species), frustum of an ellipsoidal cone (5 species), frustum of a cone (2 species) and a cone (1 species). Shell geometry is not a function of size. However, there does appear to be a correlation between shell geometry and shell volume. Species with relatively small shell volumes are described by a frustum of an ellipsoidal cone or a cone while those with a relatively large shell volume are described by a paraboloid or the frustum of a cone. / Scaling of shell and tissue components was investigated. The dry shell represents 71% of the total wet weight in small individuals to 85% in large individuals. The soma scales against size more as area than volume, possibly owing to area-dependent functions such as food capture and respiration. Mantle cavity volume is inversely related to brood size and can be correlated with differences in metabolic rates for cold water versus warm water species. / Source: Dissertation Abstracts International, Volume: 45-04, Section: B, page: 1131. / Thesis (Ph.D.)--The Florida State University, 1984.
5

MORPHOLOGY AND EVOLUTION OF THE AEGLIDAE (CRUSTACEA, DECAPODA, ANOMURA) (SOUTH AMERICA, AEGLA, SYSTEMATICS, PHENETICS CLADISTICS)

Unknown Date (has links)
Live specimens of the genus Aegla, unique crab-like decapod crustaceans endemic to freshwaters of temperate South America, were returned to aquaria at Florida State University. External morphology was described with light and scanning electron microscopy. Morphology of aeglids closely resembles that of members of the marine family Galatheidae, which are presently grouped with aeglids in the superfamily Galatheoidea Samouelle. Certain characters of Aegla are not seen in the Galatheidae or in any other family of the Galatheoidea. These characters include a complex system of dorsal carapace sutures, trichobranchiate gills, absence of male pleopods, direct development, and a tendency to be left handed (i.e., have the left cheliped larger than the right). The occurrence of some of these characters in other superfamilies of the Anomura, specifically the Paguroidea sensu largo, would seem reason to question the currently accepted phylogenetic placement of the aeglids within the Galatheoidea. / Behavior of aeglids is similar to that known for other families of the Anomura. Grooming behavior involves primarily the third maxilliped and chelate fifth pereiopod. Setal types on aeglid appendages are essentially identical to those of other anomurans. Grooming behavior and general morphology of grooming appendages in aeglids resemble those of their marine relatives in the Anomura rather than those of other freshwater decapods. This observation suggests that grooming behavior may serve as an indicator of phyletic affinity. Comparison of aeglid grooming with studies of grooming in the Paguroidea should be made with caution; apparent similarities must be tempered by the realization that few such studies exist in other anomuran superfamilies. / Phenetic and phylogenetic (cladistic) analyses were performed on 20 taxa that are now or have previously been included in the Anomura. Fifty-four morphological and ecological characters were scored for all families and selected characters illustrated for representatives of 11 families. The dendrobranchiate genus Penaeus was used as an outgroup for the cladistic analyses. Results of both phenetic and cladistic analyses depict aeglids as members of the superfamily Galatheoidea, in accordance with classifications of earlier workers. A suggested hypothesis for anomuran phylogeny separates thalassinoids from Anomura sensu stricto, places aeglids with other galatheoids, and removes lithodids and Lomis from the paguroid line. Thus, the suggested phylogeny deviates only slightly from traditional classificatory schemes. / Source: Dissertation Abstracts International, Volume: 47-06, Section: B, page: 2342. / Thesis (Ph.D.)--The Florida State University, 1986.
6

THE SYSTEMATICS OF THE SNAPPING SHRIMP ALPHEUS FROM THE EASTERN PACIFIC (DECAPODA: ALPHEIDAE)

Unknown Date (has links)
A revision of the genus Alpheus revealed 53 nominal species reported from the eastern Pacific. Of these, 23 species are considered valid and an additional 21 new species are described, resulting in 44 eastern Pacific species. A key to all 44 species is provided. Forty four species are described and 41 are illustrated. / Currently seven nominal "groups" (Macrocheles, Sulcatus, Obesomanus, Crinitus, Diadema, Brevirostris, and Edwardsii groups) have been used by various authors as a means of separating the large number of species (more than 250) in the genus Alpheus. Morphological similarities among 37 species representing the seven "groups" were examined using 68 characters. An analysis using UPGMA (unweighted pair-group method using arithmetic averages) does not clearly group the eastern Pacific species into the currently recognized groups. In general, the Macrocheles group is isolated from the other groups, Edwardsii and Crinitus groups are discrete and Sulcatus group is a heterogeneous group. / The species occur in a variety of habitats including coral (18 species), rocky intertidal (29 species), mangroves (3 species), and sand-mud (21 species). Most species occur in several habitats while a few (e.g. Alpheus lottini) are found only in a single habitat. / Seventy seven percent of the species are endemic to the eastern Pacific while 11% also occur on both coasts of the Atlantic. Five percent are shared with the Indo-West Pacific and 2% each with the western Atlantic, eastern Atlantic and Indo-West Pacific and all other tropical regions. Within the eastern Pacific, species of Alpheus occur as far north as Horseshoe Cave, Sonora County, California and as far south as Puerto Montt, Chile. Twenty species occur in the Galapagos Islands of which only one is apparently endemic. The greatest number of species (33) is found in the subregion between about 12(DEGREES)N and 2(DEGREES)N (Costa Rica, Panama, Columbia) with the number decreasing north and south of this subregion. / Source: Dissertation Abstracts International, Volume: 47-01, Section: B, page: 0100. / Thesis (Ph.D.)--The Florida State University, 1985.
7

THE DIGESTIVE SYSTEM AND LANTERN COMPLEX OF THYONELLA GEMMATA (POURTALES): STRUCTURE AND REGENERATION

Unknown Date (has links)
Source: Dissertation Abstracts International, Volume: 32-09, Section: B, page: 5539. / Thesis (Ph.D.)--The Florida State University, 1971.
8

CHARACTERIZATION AND CONTROL OF MATING AND MOLTING IN THE SPINY LOBSTER PANULIRUS ARGUS (PHOTOPERIOD, TEMPERATURE, REPRODUCTION)

Unknown Date (has links)
I examined spatio-temporal features and environmental controls of reproduction and molting in the western Atlantic spiny lobster, Panulirus argus. / Laboratory-held lobsters exhibited nocturnal rhythmicity through the molt cycle, though daily form varied as a function of activity level and molt stage. Foraging and walking peaked in the early evening; all activity ceased at or before sunrise. Ecdysis was predominantly nocturnal. / Locomotor activity and feeding rates were not equivalent through the molt cycle, though both peaked in postecdysis and early metecdysis. Locomotor activity remained high in metecdysis, decreased sharply through proecdysis, then increased near ecdysis. Activity was low during ecdysis, though lobsters were capable of intense and coordinated activity. Feeding decreased through metecdysis, increasing temporarily near proecdysis. Food intake thereafter declined rapidly and ceased in late proecdysis. Feeding resumed in postecdysis, intensifying rapidly to a maximum in late postecdysis or early metecdysis. / The frequency of agonistic interactions (not aggression per se) remained relatively constant through the cycle, peaking in metecdysis. Lobsters near ecdysis were submissive and avoided physical contact with conspecifics. / Mating in nature was initiated by large males moving about in the open during daytime. A male drew a female into sternum to sternum contact using his elongate second walking legs, eventually positioning himself upside down below the embraced female. The male vigorously contracted his abdomen during ejaculation of the spermatophore. Copulation lasted less than one minute. Females participated in courtship; prolonged pair formation was not evident. / I monitored aggression, courtship and physiological condition of lobsters collected prior to the reproductive season, and placed in semi-natural tanks with winter and summer combinations of photoperiod and temperature. Photoperiod and temperature did not alter aggression levels significantly. Long daylength stimulated courtship and gonadal development significantly more than short daylength, regardless of temperature. Warm temperatures increased the daily occurrence of courtship, and speeded breeding and molting cycles. / Large males typically initiated mating in laboratory tanks, whereas unmated females generally initiated mating only when they neared spawning. Courtship peaked near crepuscular periods, but with substantial diurnal and nocturnal incidence, contrasting the predominantly nocturnal feeding and locomotor activity. / Source: Dissertation Abstracts International, Volume: 45-11, Section: B, page: 3443. / Thesis (Ph.D.)--The Florida State University, 1984.
9

FOOD-SHARING IN COLONIES OF THE IMPORTED FIRE ANT, SOLENOPSIS INVICTA

Unknown Date (has links)
Source: Dissertation Abstracts International, Volume: 40-10, Section: B, page: 4694. / Thesis (Ph.D.)--The Florida State University, 1979.
10

INVESTIGATIONS OF COLOR, MORPHOLOGY AND DEVELOPMENT OF THE SEA WHIP, LEPTOGORGIA VIRGULATA, (LAMARCK) (CNIDARIA: OCTOCORALLIA: GORGONACEA)

Unknown Date (has links)
Fertilized eggs of the gorgonian, Leptogorgia virgulata were obtained by controlling the photoperiod. These were reared in the laboratory through metamorphosis, then transferred to field locations for growth to maturity. A precise timetable for development was obtained and compared to other octocorals. The inheritance of color was studied by transmission genetics. Spicular color is governed by a single gene with four alleles: Magenta, orange, yellow and metachromatic. The first three are codominant; while metachromatic is dominant to magenta, but recessive to both orange and yellow. Color variance and distribution in the population of Leptogorgia at Alligator Harbor, Florida could be explained on the basis of genetics and growth. An attempt was made to analyze the spicules by physical and chemical techniques. The coloring material is derived from a colorless organic molecule that becomes colored when bound into the calcium carbonate matrix of the spicule. Attempts to reconstitute the pigment-crystal complex by precipitation or recrystallization were unsuccessful. The ectoparasitic snail, Siminialena uniplicata, feeds on Leptogorgia and possesses a shell that matches its host in color. The snail shell coloration is obtained directly from the tissues of the host coral; the color was not extracted from ingested spicules. / Source: Dissertation Abstracts International, Volume: 41-03, Section: B, page: 0849. / Thesis (Ph.D.)--The Florida State University, 1980.

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