Incidence of male intersex in adult Pacific lamprey (Entosphenus tridentatus), with a brief discussion of intersex vs. hermaphroditism in lampreys (Petromyzontiformes)

2012 ◽  
Vol 90 (9) ◽  
pp. 1201-1206 ◽  
Author(s):  
Benjamin J. Clemens ◽  
Stacia A. Sower ◽  
Stan van de Wetering ◽  
Carl B. Schreck
Keyword(s):  
Fresh Water ◽  
Histological Examination ◽  
The Other ◽  
Spawning Migration ◽  
Pacific Lamprey ◽  
Primary Growth ◽  
Entosphenus Tridentatus ◽  
In The Beginning

We report the incidence of male intersex in adult Pacific lamprey ( Entosphenus tridentatus (Richardson, 1836)) during their pre-spawning migration in fresh water. Although “hermaphrodites” have been suggested in other adult lampreys, this is the first detailed description and discussion of this phenomenon. A total of 0.5% of our adult Pacific lamprey from Willamette Falls (2 out of 427 adults) were intersex, with oocytes in the testes. This phenomenon was identifiable only by histological examination. The testes of the intersex males were immature, in the beginning stages of meiosis. One intersex male possessed primary growth or perinucleolar stage oocytes loosely interspersed throughout the testes, and the other possessed at least 6 mid-vitellogenic oocytes (0.6 mm, mean long diameter) separate from the testes. Because premetamorphic lamprey can possess both female and male gonial cells, we hypothesize that intersex is a remnant larval trait and that these fish failed to fully develop into males during metamorphosis.

Pre-spawning migration of adult Pacific lamprey, Entosphenus tridentatus, in the Willamette River, Oregon, U.S.A.

2011 ◽  
Vol 93 (2) ◽  
pp. 245-254 ◽  
Author(s):  
Benjamin J. Clemens ◽  
Matthew G. Mesa ◽  
Robert J. Magie ◽  
Douglas A. Young ◽  
Carl B. Schreck
Keyword(s):  
Spawning Migration ◽  
Pacific Lamprey ◽  
Willamette River ◽  
Entosphenus Tridentatus

Maturation characteristics and life-history strategies of the Pacific lamprey, Entosphenus tridentatus

2013 ◽  
Vol 91 (11) ◽  
pp. 775-788 ◽  
Author(s):  
Benjamin J. Clemens ◽  
Stan van de Wetering ◽  
Stacia A. Sower ◽  
Carl B. Schreck
Keyword(s):  
Life History ◽  
Fresh Water ◽  
Body Mass ◽  
Life Histories ◽  
Oocyte Diameter ◽  
Liver Lipids ◽  
Pacific Lamprey ◽  
Total Length ◽  
Significant Difference ◽  
Entosphenus Tridentatus

Lampreys (Petromyzontiformes) have persisted over millennia and now suffer a recent decline in abundance. Complex life histories may have factored in their persistence; anthropogenic perturbations in their demise. The complexity of life histories of lampreys is not understood, particularly for the anadromous Pacific lamprey, Entosphenus tridentatus Gairdner, 1836. Our goals were to describe the maturation timing and associated characteristics of adult Pacific lamprey, and to test the null hypothesis that different life histories do not exist. Females exhibited early vitellogenesis – early maturation stages; males exhibited spermatogonia – spermatozoa. Cluster analyses revealed an “immature” group and a “maturing–mature” group for each sex. We found statistically significant differences between these groups in the relationships between (i) body mass and total length in males; (ii) Fulton’s condition factor and liver lipids in males; (iii) the gonadosomatic index (GSI) and liver lipids in females; (iv) GSI and total length in females; (v) mean oocyte diameter and liver lipids; and (vi) mean oocyte diameter and GSI. We found no significant difference between the groups in the relationship of muscle lipids and body mass. Our analyses support rejection of the hypothesis of a single life history. We found evidence for an “ocean-maturing” life history that would likely spawn within several weeks of entering fresh water, in addition to the formerly recognized life history of spending 1 year in fresh water prior to spawning—the “stream-maturing” life history. Late maturity, semelparity, and high fecundity suggest that Pacific lamprey capitalize on infrequent opportunities for reproduction in highly variable environments.

BIOCHEMICAL STUDIES ON SOCKEYE SALMON DURING SPAWNING MIGRATION: IV. THE NON-PROTEIN NITROGENOUS CONSTITUENTS OF THE MUSCLE

1958 ◽  
Vol 36 (8) ◽  
pp. 833-838 ◽  
Author(s):  
J. D. Wood
Keyword(s):  
Sockeye Salmon ◽  
The Other ◽  
Spawning Migration ◽  
Female Fish ◽  
Male And Female ◽  
Low Level ◽  
Early Stages ◽  
Biochemical Studies

The non-protein nitrogenous constituents of muscle of migrating sockeye salmon were investigated. These constituents were found to be the same in both male and female fish and were present in approximately the same amounts in both sexes. The histidine content of the muscle in all fish decreased to one fifth of the original value during the early stages of the migratory journey and remained at the low level thereafter. Some of the other constituents changed to a smaller extent, usually increasing in the later stages of the migration. This was especially noticeable in female fish. However, the increase in the concentration of these constituents in the muscle was due to a decrease in the amount of muscle in the fish rather than to an increase in the amounts of the compounds themselves.

Biochemical Studies on Sockeye Salmon During Spawning Migration: XI. The Free Histidine Content of the Tissues

1960 ◽  
Vol 17 (3) ◽  
pp. 347-351 ◽  
Author(s):  
J. D. Wood ◽  
D. W. Duncan ◽  
M. Jackson
Keyword(s):  
Amino Acid ◽  
Sockeye Salmon ◽  
Alimentary Tract ◽  
Oncorhynchus Nerka ◽  
The Other ◽  
Spawning Migration ◽  
Fraser River ◽  
Initial Value ◽  
Spawning Grounds ◽  
Biochemical Studies

During the first 250 miles (400 km) of spawning migration of Fraser River sockeye salmon (Oncorhynchus nerka) the free histidine content of the muscle, alimentary tract, and head+skin+bones+tail decreased to a small fraction of the initial value. A further decrease occurred in the levels of this amino acid in the alimentary tract during the subsequent 415-mile (657-km) migration to the spawning grounds, no change being observed with the other tissues. Comparatively small changes in free histidine were found with heart, spleen, liver, kidney and gonads during migration.

scholarly journals The Influence of Charismatic Church Development on Religious Christians Life in the City of Semarang 1970-2015

2020 ◽  
Vol 4 (2) ◽  
pp. 155-169
Author(s):  
Oni Andhi Asmara ◽  
Endang Susilowati ◽  
Agustinus Supriyono
Keyword(s):  
Rapid Development ◽  
The Other ◽  
Major Influence ◽  
Church Development ◽  
Christian Life ◽  
Worship Services ◽  
The Times ◽  
In The Beginning ◽  
Historical Methods ◽  
The City

This article discusses the development of the Charismatic church on the Christians life in Semarang City in 1970-2015 using historical methods and using social religion approach. Since its inception in 1970, the Charismatic church in the city of Semarang has had a major influence on the Christian life in the city. A series of innovations in worship and evangelism that are adapted to the times have made the Charismatic church much in demand by Christians in big cities, one of them is Semarang. Christian interest in the Charismatic church can be seen from the development of the number of Charismatic churches in the city of Semarang. One of the Charismatic churches that is experiencing rapid development is JKI Injil Kerajaan. In the beginning, there were 25 people in the congregations. One decade later it reached 3,557 people and continued to increase to 13,324 people on the next decade. This rapid development has brought significant changes to the Christians life in the city of Semarang. It can be seen, among others, from the increasing number of churches that are full of Charismatic churches at worship services. But on the other hand, the presence of Charismatic church with a new pattern of worship caused less harmonious relationship between non-Charismatic churches and charismatic churches as the result of the high increasing number of original church people who moved to the Charismatic church. It is because Christians in Semarang are mostly more interested in taking worship in the Charismatic church.

Historical Account or Discourse on Identity? A Reexamination of Fulbe Hegemony and Autochthonous Submission in Banyo

1998 ◽  
Vol 25 ◽  
pp. 93-110 ◽  
Author(s):  
Quentin Gausset
Keyword(s):  
Nineteenth Century ◽  
The Other ◽  
Islamic State ◽  
Local Populations ◽  
Northern Cameroon ◽  
Definition Of ◽  
Historical Accounts ◽  
In The Beginning ◽  
Almost All ◽  
The Military

Traditional accounts of the nineteenth-century Fulbe conquest in northern Cameroon tell roughly the same story: following the example of Usman Dan Fodio in Nigeria, the Fulbe of Cameroon organized in the beginning of the nineteenth century a “jihad” or a “holy war” against the local pagan populations to convert them to Islam and create an Islamic state. The divisions among the local populations and the military superiority of the Fulbe allowed them to conquer almost all northern Cameroon. They forced those who submitted to give an annual tribute of goods and servants, and they raided the other groups. In these traditional accounts the Fulbe are presented as unchallenged masters, while the local populations are depicted as slaves who were powerless over their fate; their role in the conquest of the region and in the administration of the new political order is supposed to have been insignificant.I will show that, on the contrary, in the area of Banyo the Wawa and Bute played a crucial role in the conquest of the sultanate and in its administration. I will then re-examine the cliche that all members of the local populations were the slaves of the Fulbe by distinguishing the fate of the Wawa and Bute on one side from that of the Kwanja and Mambila on the other, and by showing the importance of the Fulbe's identity in shaping the definition of slavery. Finally I will argue that, if the historical accounts found in the scientific literature invariably insist on Fulbe hegemony and minimize the role played by the local populations, it is because those accounts are often based on Fulbe traditions, and because these traditions are remodeled by the Fulbe in order to correspond to their discourse on identity.

Disequilibrium 1: Potential Gradients and Flows

1993 ◽  
Author(s):  
Brian Bayly
Keyword(s):  
Fresh Water ◽  
Flow Rate ◽  
Real Life ◽  
Water Levels ◽  
Bulk Flow ◽  
The Other ◽  
Water Salt ◽  
Potential Gradients ◽  
The Right ◽  
Two Sides

As in Chapter 2, so again here the intention is to review ideas that are already familiar, rather than to introduce the unfamiliar; to build a springboard, but not yet to leap off into space. The familiar idea is of flow down a gradient—water running downhill. Parallels are electric current in a wire, salt diffusing inland from the sea, heat flowing from the fevered brow into the cool windowpane, and helium diffusing through the membrane of a helium balloon. For any of these, we can imagine a linear relation: . . . Flow rate across a unit area = (conductivity) x (driving gradient) . . . where the conductivity retains a constant value, and if the other two quantities change, they do so in a strictly proportional way. Real life is not always so simple, but this relation serves to introduce the right quantities, some suitable units and some orders of magnitude. For present purposes, the second and fourth of the examples listed are the most relevant. To make comparison easier we imagine a barrier through which salt can diffuse and through which water can percolate, but we imagine circumstances such that only one process occurs at a time. Specifically, imagine a lagoon separated from the ocean by a manmade dike of gravel and sand 4 m thick, as in Figure 3.1. If the lagoon is full of seawater but the water levels on the two sides of the dike are unequal, water will percolate through the dike, whereas if the levels are the same and the dike is saturated but the lagoon is fresh water, salt will diffuse through but there will be no bulk flow of water. (More correctly, because seawater and fresh water have different densities, and because of other complications, the condition of no net water flow would be achieved in circumstances a little different from what was just stated. For present purposes all we need is the idea that conditions exist where water does not percolate but salt does diffuse.) For flow of water driven by a pressure gradient, suitable units are shown in the upper part of Table 3.1 and for diffusion of salt driven by a concentration gradient, suitable units are shown in the lower part.

scholarly journals Morphology, development and heterochrony of the carapace of Giant Amazon River Turtle Podocnemis expansa (Testudines, Podocnemidae)

2016 ◽  
Vol 36 (5) ◽  
pp. 436-446 ◽  
Author(s):  
Lucélia G. Vieira ◽  
André L.Q. Santos ◽  
Léa R. Moura ◽  
Stiwens R.T. Orpinelli ◽  
Kleber F. Pereira ◽  
...  
Keyword(s):  
Close Relation ◽  
Staining Technique ◽  
The Other ◽  
Amazon River ◽  
Direct Relation ◽  
Podocnemis Unifilis ◽  
Podocnemis Expansa ◽  
Morphology Development ◽  
In The Beginning ◽  
Osseous Structure

Abstract: With aim to report the ontogeny of the osseous elements of the carapace in Peurodiras, 62 embryos and 43 nestlings of Podocnemis expansa were collected and submitted to the clearing and staining technique of bones and cartilages and study of serial histological slices. The carapace has mixed osseous structure of endo and exoskeleton, formed by 8 pairs of costal bones associated with ribs, 7 neural bones associated with neural arches, 11 pairs of peripheral bones, 1 nuchal, 1 pygal and 1 suprapygal. This structure begins its formation in the beginning of stage 16 with the ossification of the periosteal collar of the ribs. With exception of the peripheral bones, the other ones begin their ossification during the embrionary period. In histologic investigation it was found that the costal bones and neural bones have a close relation to the endoskeleton components, originating themselves as intramembranous expansions of the periosteal collar of the ribs and neural arches, respectively. The condensation of the mesenchyme adjacent to the periosteal collar induces the formation of spikes that grow in trabeculae permeated by fibroblasts below the dermis. The nuchal bone also ossifies in an intramembranous way, but does not show direct relation to the endoskeleton. Such information confirms those related to the other Pleurodira, mainly with Podocnemis unifilis, sometimes with conspicuous variations in the chronology of the ossification events. The formation of dermal plates in the carapace of Pleurodira and Criptodira follow the same pattern.

Art. VII.—Extracts from Report on the Islands and Antiquities of Bahrein

1880 ◽  
Vol 12 (2) ◽  
pp. 189-201
Author(s):  
Durand ◽  
H. C. Rawlinson
Keyword(s):  
Fresh Water ◽  
The Other ◽  
Clear Sky ◽  
Exact Position ◽  
As If

These Islands, from which the Portuguese were expelled by a British fleet aiding Shah Abbas in 1622 A.D., and of which the advantages were tersely put to me by a native the other day in the words, “The land is silver and the sea is pearl,” are situated generally in lat. 26° and long. 50°, the exact position of the Portuguese fort on the larger island being given as lat. 26° 13′ 53„ N., long. 50° 31′ 45„ E. They are surrounded by shoal water on every side, which greatly adds to the beauty of the place. Thus, on looking out to sea on the morning of a clear sky and a fresh nor'-wester, it would seem as if Nature, at all times lavish of effect, had here, however, exhausted every tint of living green in her paint box; and then, wearying of the effort, had splashed an angry streak of purple into the foreground. The water itself is so clear that you can see far down into the coral depths, while springs of fresh water bubble up through the brine, both near the entrance of the harbour and at several other places along the coast.

scholarly journals Predicting larval metamorphosis of Pacific lamprey Entosphenus tridentatus through measurements of length and mass

2020 ◽  
Vol 97 (3) ◽  
pp. 804-816
Author(s):  
Timothy A. Whitesel ◽  
Michelle McGree ◽  
Gregory S. Silver
Keyword(s):  
Larval Metamorphosis ◽  
Pacific Lamprey ◽  
Entosphenus Tridentatus
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