scholarly journals Female reproductive biology, and age of deep-sea squid Histioteuthis miranda from southern Africa

2009 ◽  
Vol 66 (9) ◽  
pp. 1868-1872 ◽  
Author(s):  
Hendrik Jan T. Hoving ◽  
Marek R. Lipiński
Keyword(s):  
Reproductive Biology ◽  
Southern Africa ◽  
Deep Sea ◽  
Reproductive Strategy ◽  
Marine Science ◽  
Potential Fecundity ◽  
Male And Female ◽  
Short Period ◽  
Daily Deposition

Abstract Hoving, H. J. T., and Lipiński, M. R. 2009. Female reproductive biology, and age of deep-sea squid Histioteuthis miranda from southern Africa. – ICES Journal of Marine Science, 66: 1868–1872. Data on female reproductive strategy and male and female length–weight relationships and age are presented for the mesopelagic squid Histioteuthis miranda. Females exhibit synchronous ovulation, indicating that eggs are spawned at once or over a short period. The maximum potential fecundity seems to range from 89 000 to 148 000 oocytes. Assuming daily deposition of statolith increments, maturing females were 10–15 months old. Male H. miranda mature young (∼6 months) and reach at least 15 months old.

scholarly journals Sexual ratio and floral biology of the dioecious Neea theifera Oerst. (Nyctaginaceae) in a cerrado rupestre of central Brazil

2011 ◽  
Vol 25 (4) ◽  
pp. 785-792 ◽  
Author(s):  
Felipe Wanderley Amorim ◽  
Clesnan Mendes-Rodrigues ◽  
Pietro Kiyoshi Maruyama ◽  
Paulo Eugênio Oliveira
Keyword(s):  
Resource Allocation ◽  
Sex Ratio ◽  
Reproductive Biology ◽  
Reproductive Strategy ◽  
Pollen Viability ◽  
Floral Biology ◽  
Pollinator Limitation ◽  
Dioecious Species ◽  
Male And Female ◽  
Pollination Success

Dioecy is characterized by a complete separation of sexual functions on male and female plants. It has evolved many times in flowering plants and is widespread among distinct Angiosperm families. It is viewed as a reproductive strategy to reduce endogamy, and to promote optimal resource allocation between male and female sexual functions. Neea theifera is a common species in Cerrado, neotropical savannas in Brazil, but information regarding its reproductive biology is still incomplete. In order to investigate how environmental conditions possibly affect this dioecious species, we studied its floral biology, sex ratio and spatial distribution of sexual morphs along a soil-altitudinal gradient. The sex ratio did not significantly deviate from the expected 1:1 ratio. However, flower abundance in the population was significantly biased towards staminate flowers. Female individuals were larger than male individuals and plant size was negatively correlated with altitude, but did not differ between sexual morphs. The population did not show spatial segregation of sexes and male individuals were sexually mature earlier than female ones. Staminate flowers were larger than pistillate flowers and presented high pollen viability. Meliponini bees, small flies and thrips were potential pollinators, but pollination success was very low. Dioecy in N. theifera corroborates many general features of this reproductive strategy, such as woody habit, inconspicuous flowers, pollination by small generalist insects and differential resource allocation between male and female plants. However, reproduction in this species seems to be impaired by pollinator limitation. The results showed that the soil-altitude gradient influenced the growth pattern of the species and may play an important role in its reproductive biology but did not affect dioecy directly.

scholarly journals First Description of Reproductive Behavior and Alternative Reproductive Strategy in the Deep-sea Fish, Careproctus pellucidus.

2021 ◽  
Author(s):  
Toshiaki Mori ◽  
Kazuya Fukuda ◽  
Syouko Ohtsuka ◽  
Shinya Yamauchi ◽  
Tatsuki Yoshinaga
Keyword(s):  
Reproductive Biology ◽  
Reproductive Behavior ◽  
Deep Sea ◽  
Reproductive Strategy ◽  
Aggressive Display ◽  
Territorial Male ◽  
First Report ◽  
Spawning Substrate ◽  
Alternative Reproductive Strategy ◽  
Sea Fish

Abstract The reproductive biology of deep-sea fishes is largely unknown because of the difficulty of behavioral observations in this environment. In this study, the reproductive behavior of the deep-sea snailfish, Careproctus pellucidus, which lives at depths > 200 m, was observed in an aquarium. To the best of our knowledge, this is the first report to observe and describe the reproductive behavior of deep-sea fish under free-living conditions. Fishes were collected at a depth of approximately 300 m (36°70′ N; 141°00′ E) on July and August 2018 and kept for observation until March 2019. We observed that almost all spawnings took place between one male and one female. Males defended a spawning substrate against other males and exhibited body-wiggling behavior for both courtship and aggressive display. Females visited the male’s territory and spawned a demersal adhesive egg mass on the substrate. The territorial male then sought the spawned eggs using filamentous rays in the lower pectoral-fin lobe and released sperm when he located the eggs. Males remained near the spawning substrate after spawning but did not perform any parental care. Notably, sneaking behavior by a non-territorial male was observed in one case; this is the first report of this alternative reproductive strategy (or tactic) in a deep-sea fish. Our study reveals the unique reproductive biology of the deep-sea fish, C. pellucidus, which does not depend on visual information and uses other sensory modalities.

Loss of sleep or loss of dark?

2018 ◽  
Author(s):  
Richard G. Stevens
Keyword(s):  
Mood Disorders ◽  
Deep Sea ◽  
Short Distance ◽  
Water Surface ◽  
Ocean Floor ◽  
Physiological Adaptation ◽  
Poor Sleep ◽  
Short Period ◽  
The World ◽  
Night And Day

Before electricity, night was something akin to the deep sea: just as we could not descend much below the water surface, we also could not investigate the night for more than a short distance, and for a short period of time. Things changed with two inventions: the Bathysphere to plumb the ocean floor, and electricity to light the night for sustained exploration. Exploration led to dominance, and night has become indistinguishable from day in many parts of the world. The benefits of electric light are myriad, but so too are the possible detriments of loss of dark at night, including poor sleep, obesity, diabetes, cancer, and mood disorders. Our primordial physiological adaptation to the night and day cycle is being flummoxed by the maladaptive signals coming from electric lighting around the clock. The topic of sleep and health has finally attained scientific respect, but dark and health is not yet fully appreciated.

Glossary of terms used in developmental and reproductive toxicology (IUPAC Recommendations 2016)

2016 ◽  
Vol 88 (8) ◽  
pp. 713-830
Author(s):  
John H. Duffus ◽  
Michael Schwenk ◽  
Douglas M. Templeton
Keyword(s):  
Risk Assessment ◽  
Reproductive Biology ◽  
Environmental Risk ◽  
Environmental Risk Assessment ◽  
Primary Objective ◽  
Human Reproduction ◽  
Reproductive Systems ◽  
Teratogenic Effects ◽  
Male And Female ◽  
Medical Practitioners

Abstract The primary objective of this glossary is to give clear definitions for those who contribute to studies relevant to these disciplines, or who must interpret them, but are not themselves reproductive physiologists or physicians. This applies especially to chemists who need to understand the literature of reproductive and teratogenic effects of substances without recourse to a multiplicity of other glossaries or dictionaries. The glossary includes terms related to basic and clinical reproductive biology and teratogenesis, insofar as they are necessary for a self-contained document, particularly terms related to diagnosing, measuring, and understanding the effects of substances on the embryo, the fetus, and on the male and female reproductive systems. The glossary consists of about 1200 primary alphabetical entries and includes Annexes of common abbreviations and examples of chemicals with known effects on human reproduction and development. The authors hope that toxicologists, pharmacologists, medical practitioners, risk assessors, and regulatory authorities are among the groups who will find this glossary helpful, in addition to chemists. In particular, the glossary should facilitate the worldwide use of chemical terminology in relation to occupational and environmental risk assessment.

scholarly journals Histologic Examination of a Sea Pig (Scotoplanes sp.) Using Bright Field Light Microscopy

2021 ◽  
Vol 9 (8) ◽  
pp. 848
Author(s):  
Elise E. B. LaDouceur ◽  
Linda A. Kuhnz ◽  
Christina Biggs ◽  
Alicia Bitondo ◽  
Megan Olhasso ◽  
...  
Keyword(s):  
Deep Sea ◽  
Body Wall ◽  
Monterey Bay ◽  
Bright Field ◽  
Male And Female ◽  
Rete Mirabile ◽  
Lateral Body ◽  
Bright Field Microscopy ◽  
Microscopic Findings ◽  
Tube Feet

Sea pigs (Scotoplanes spp.) are deep-sea dwelling sea cucumbers of the phylum Echinodermata, class Holothuroidea, and order Elasipodida. Few reports are available on the microscopic anatomy of these deep-sea animals. This study describes the histologic findings of two, wild, male and female Scotoplanes sp. collected from Monterey Bay, California. Microscopic findings were similar to other holothuroids, with a few notable exceptions. Sea pigs were bilaterally symmetrical with six pairs of greatly enlarged tube feet arising from the lateral body wall and oriented ventrally for walking. Neither a rete mirabile nor respiratory tree was identified, and the large tube feet may function in respiration. Dorsal papillae protrude from the bivium and are histologically similar to tube feet with a large, muscular water vascular canal in the center. There were 10 buccal tentacles, the epidermis of which was highly folded. Only a single gonad was present in each animal; both male and female had histologic evidence of active gametogenesis. In the male, a presumed protozoal cyst was identified in the aboral intestinal mucosa, and was histologically similar to previous reports of coccidians. This work provides control histology for future investigations of sea pigs and related animals using bright field microscopy.

The Reproductive Biology of Ophiacantha Bidentata (Echinodermata: Ophiuroidea) From The Rockall Trough

1982 ◽  
Vol 62 (1) ◽  
pp. 45-55 ◽  
Author(s):  
P. A. Tyler ◽  
J. D. Gage
Keyword(s):  
Reproductive Biology ◽  
Deep Water ◽  
Larval Stage ◽  
North Pacific ◽  
Deep Sea ◽  
Direct Development ◽  
The Arctic ◽  
Shallow Waters ◽  
Arctic Seas ◽  
Rockall Trough

INTRODUCTIONOphiacantha bidentata (Retzius) is a widespread arctic-boreal ophiuroid with a circumpolar distribution in the shallow waters of the Arctic seas and penetrating into the deep sea of the.North Atlantic and North Pacific (Mortensen, 1927, 1933a; D'yakonov, 1954). Early observations of this species were confined to defining zoogeo-graphical and taxonomic criteria including the separation of deep water specimens as the variety fraterna (Farran, 1912; Grieg, 1921; Mortensen, 1933a). Mortensen (1910) and Thorson (1936, pp. 18–26) noted the large eggs (o.8 mm diameter) in specimens from Greenland and Thorson (1936) proposed that this species had ‘big eggs rich in yolk, shed directly into the sea. Much reduced larval stage or direct development’. This evidence is supported by observations of O. bidentata from the White and Barents Seas (Semenova, Mileikovsky & Nesis, 1964; Kaufman, 1974)..

Sex difference in the cytosolic and nuclear distribution of androgen receptor in mouse submandibular gland

1986 ◽  
Vol 108 (2) ◽  
pp. 267-273 ◽  
Author(s):  
S. Kyakumoto ◽  
R. Kurokawa ◽  
Y. Ohara-Nemoto ◽  
M. Ota
Keyword(s):  
Androgen Receptor ◽  
Nuclear Receptors ◽  
Binding Sites ◽  
Androgen Receptors ◽  
Dissociation Constants ◽  
Scatchard Analysis ◽  
Male And Female ◽  
Short Period ◽  
Almost All ◽  
Androgen Binding

ABSTRACT Cytosol and nuclear androgen receptors in submandibular glands of male and female mice were measured by an exchange assay at 0 °C. The binding of [3H]methyltrienolone to cytosol receptors in females was mostly saturated within a short period of incubation (3 h), whereas the saturation was much slower in males; suggesting that almost all of the cytosol receptors were unoccupied in females and the receptors were partially occupied in males. Nuclear receptors were extracted with pyridoxal 5′-phosphate (5 mmol/l) from nuclear fractions with 93–95% efficiency. The exchange of the bound steroids occurred by 24–48 h at 0 °C, suggesting that most of the nuclear androgen receptor was occupied. The binding was low at higher temperatures, probably due to inactivation of the receptor. Scatchard analysis showed that the apparent dissociation constants of cytosol and nuclear receptors were similar (0·8 and 0·9 nmol/l respectively) in both sexes. On the other hand, the number of androgen-binding sites in the nucleus was much higher in males than in females (1052 fmol/mg DNA and 32 fmol/mg DNA respectively), while the number in the cytosol was higher in females than in males (512 fmol/mg DNA and 368 fmol/mg DNA respectively). These observations show that androgen receptors exist mainly (74%) in the nuclei of males, while they exist mostly (94%) in the cytosol of females. J. Endocr. (1986) 108, 267–273

COLLABORATIVE TACTICS FOR NESTSITE SELECTION BY PAIRS OF BLUE FOOTED BOOBIES

Behaviour ◽  
2002 ◽  
Vol 139 (11-12) ◽  
pp. 1383-1412 ◽  
Author(s):  
Hugh Drummond ◽  
Miriam Calderón-De Anda ◽  
Carmen Perez ◽  
Judy Stamps
Keyword(s):  
Reproductive Biology ◽  
Veto Power ◽  
Male And Female ◽  
Communication Signal ◽  
Joint Decisions ◽  
Clutch Initiation ◽  
A Site ◽  
Behavioural Strategies

AbstractThe dual concern model suggests that pairs of animals can use four different behavioural strategies to resolve disputes that arise when making joint decisions. Based on their reproductive biology, we predicted that mated pairs of blue footed boobies would use one of these strategies, collaboration, when deciding on a location for their nest. Many of the behaviour tactics diagnostic of collaboration were observed in boobies. For instance, nestsite selection was accompanied by extensive exchanges of a specialized communication signal (nestpointing), rates of nestpointing at a given site were strongly related to the likelihood that a pair would select that site for their nest, couples in which the male and female 'disagreed' about the merits of an initial site went on to investigate additional sites together ('expanding the pie'), individuals pointed at maximal rates at a site only after their partner had already pointed at that same site ('feeling out procedures'), and both sexes appeared to have 'veto power' over potential nestsites, in the sense that a site was virtually never accepted for the nest if one of the two partners failed to point at that site prior to clutch initiation. These results support the hypothesis that mated pairs of blue footed boobies may use collaborative tactics when selecting a nestsite; descriptive accounts suggest that similar tactics may occur in other birds in which mated pairs jointly decide on the location for their nest.

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