3. Reproduction and life history

2021 ◽  
pp. 48-71
Author(s):  
T. S. Kemp
Keyword(s):  
Life History ◽  
Life Cycle ◽  
Parental Care ◽  
Juvenile Stage ◽  
Number Of Species ◽  
Area Of Interest ◽  
Rapid Transformation

‘Reproduction and life history’ discusses the life cycle of amphibians, which includes a fully aquatic, juvenile stage. This is the larva, known in the anurans as the tadpole. It feeds and grows, and eventually undergoes a rapid transformation, or metamorphosis, into the adult. Metamorphosis can take place in as little as nine days from the eggs hatching. A small number of species in all three amphibian orders have evolved the most complete mode of parental care of all, viviparity, which is bearing the young live. An area of interest here is the courtship and mating practices of amphibians.

On the genus Holophryxus (Isopoda: Epicaridea), with description of the male and redescription of the female of Holophryxus acanthephyrae

1986 ◽  
Vol 66 (2) ◽  
pp. 303-314 ◽  
Author(s):  
M. B. Jones ◽  
G. Smaldon
Keyword(s):  
Life History ◽  
Life Cycle ◽  
Definitive Host ◽  
Final Host ◽  
Juvenile Stage ◽  
Decapod Crustaceans ◽  
Body Form ◽  
Larval Stages ◽  
History Of ◽  
The One

INTRODUCTIONAdults of the isopod genus Holophryxus (Dajidae) occur as ectoparasites on natant decapod crustaceans, but little is known of the ecology and life-history of most species. Species of Holophryxus are thought to have a typical dajid life cycle involving an intermediate host (copepod), a definitive host (prawn) and three larval stages (epicaridium, microniscus, cryptoniscus), and the one species for which details are available fits this pattern (Coyle & Mueller, 1981). The final host is infected by the cryptoniscus, a stage superficially resembling a cirolanid isopod, and the first cryptoniscus to settle loses its isopod-like appearance and develops through a juvenile stage into a rather inflated, highly modified female (Coyle & Mueller, 1981). Any subsequent settler becomes a male, retains the small cryptoniscus body form and lives within the marsupium of the female.

Experimentally increased costs of parental care are shunted to offspring in species with extended care

2019 ◽  
Author(s):  
Gretchen F. Wagner ◽  
Emeline Mourocq ◽  
Michael Griesser
Keyword(s):  
Life History ◽  
Parental Care ◽  
Total Duration ◽  
Bird Species ◽  
Life History Strategy ◽  
Experimental Treatment ◽  
Cost Of Care ◽  
Adult Survival ◽  
Supporting Evidence ◽  
Trade Offs

Biparental care systems are a valuable model to examine conflict, cooperation, and coordination between unrelated individuals, as the product of the interactions between the parents influences the fitness of both individuals. A common experimental technique for testing coordinated responses to changes in the costs of parental care is to temporarily handicap one parent, inducing a higher cost of providing care. However, dissimilarity in experimental designs of these studies has hindered interspecific comparisons of the patterns of cost distribution between parents and offspring. Here we apply a comparative experimental approach by handicapping a parent at nests of five bird species using the same experimental treatment. In some species, a decrease in care by a handicapped parent was compensated by its partner, while in others the increased costs of care were shunted to the offspring. Parental responses to an increased cost of care primarily depended on the total duration of care that offspring require. However, life history pace (i.e., adult survival and fecundity) did not influence parental decisions when faced with a higher cost of caring. Our study highlights that a greater attention to intergenerational trade-offs is warranted, particularly in species with a large burden of parental care. Moreover, we demonstrate that parental care decisions may be weighed more against physiological workload constraints than against future prospects of reproduction, supporting evidence that avian species may devote comparable amounts of energy into survival, regardless of life history strategy.

The life-cycle of Echinoparyphium hydromyos sp.nov. (Digenea: Echinostomatidae) from the Australian water-rat

Parasitology ◽  
1967 ◽  
Vol 57 (1) ◽  
pp. 19-30 ◽  
Author(s):  
L. Madeline Angel
Keyword(s):  
Life History ◽  
Life Cycle ◽  
Experimental Work ◽  
Field Work ◽  
Type Material ◽  
South Australian Museum ◽  
The South ◽  
Australian Water ◽  
Australian Museum ◽  
Hydromys Chrysogaster

Echinoparyphium hydromyos sp.nov. with forty-five collar spines is described from the Australian water rat, Hydromys chrysogaster Geoffr.The cercaria occurs naturally in Plananisus isingi (Cotton & Godfrey), and all stages in the life-history have been demonstrated experimentally.Encystation occurs in the kidneys of tadpoles.The adult is most closely related to Echinoparyphium recurvatum (Linstow). It differs from this in its greater number of eggs and in its life-history. E. recurvatum occurs predominantly in birds, and is rarely found naturally in mammals. E. hydromyos has been found only in a mammal.Cercaria echinoparyphii hydromyos is compared with C. clelandae Johnston and Angel; it differs from the latter in the ‘compound’ nature of the excretory granules. The adult of C. clelandae has not been demonstrated in spite of a number of experiments to determine it.Type material has been deposited in the South Australian Museum.I wish to acknowledge the help given by my colleague, Patricia M. Thomas, in field work and in other ways, and by Mr Ian Smith, of this department, in the experimental work on life-history studies.

Life history and pathogenicity of Eimeria adenoeides Moore & Brown, 1951, in the turkey poult

Parasitology ◽  
1958 ◽  
Vol 48 (1-2) ◽  
pp. 70-88 ◽  
Author(s):  
M. J. Clarkson
Keyword(s):  
Life History ◽  
Life Cycle ◽  
Great Britain ◽  
General Pattern ◽  
Blood Picture ◽  
Highly Pathogenic ◽  
Turkey Poult ◽  
Turkey Poults ◽  
Cell Inoculation ◽  
Microscopic Pathology

The life cycle and pathogenicity of a strain of Eimeria isolated in Great Britain from turkey poults by single cell inoculation are described and, using the criteria laid down by Tyzzer, the species is identified as E. adenoeides.The life cycle is of the same general pattern as in other Eimeria species, consisting of two asexual and one sexual generations.The organism is highly pathogenic for young poults, a dose of 200,000 oocysts producing 100 % mortality in 3-week-old birds and smaller doses causing reduced weight gain. Birds 11 weeks old resisted a dose of 3 million oocysts.The gross and microscopic pathology of the infection is described. No changes were found in the blood picture.

The reproduction and larval development of Nereis fucata (Savigny)

1959 ◽  
Vol 38 (1) ◽  
pp. 65-80 ◽  
Author(s):  
J. B. Brown-Gilpin
Keyword(s):  
Life History ◽  
Life Cycle ◽  
Experimental Methods ◽  
Point Of View ◽  
Hermit Crabs ◽  
Special Importance ◽  
Reproductive Patterns ◽  
Complete Life Cycle ◽  
History Of ◽  
The Many

The wide variety of reproductive patterns and behaviour in the many species of Nereidae already studied clearly justifies further research. But the life history of Nereis fucata (Savigny) is not only of interest from the comparative point of view. Its commensal habit (it occurs within shells occupied by hermit crabs) immediately gives it a special importance. This alone warrants a detailed study, particularly as no commensal polychaete has yet been reared through to metamorphosis and settlement on its host (Davenport, 1955; Davenport & Hickok, 1957). The numerous interesting problems which arise, and the experimental methods needed to study them, are, however, beyond the range of a paper on nereid development. It is therefore proposed to confine the present account to the reproduction and development up to the time when the larvae settle on the bottom. The complete life cycle, the mechanism of host-adoption, and related topics, will be reported in later papers.

scholarly journals A STUDY OF THE LIFE HISTORY OF TRICHOBILHARZIA CAMERONI SP. NOV. (FAMILY SCHISTOSOMATIDAE)

1953 ◽  
Vol 31 (4) ◽  
pp. 351-373 ◽  
Author(s):  
Liang-Yu Wu
Keyword(s):  
Life History ◽  
Life Cycle ◽  
Room Temperature ◽  
Migratory Birds ◽  
Local Infection ◽  
Domestic Ducks ◽  
Ottawa River ◽  
Daughter Sporocyst ◽  
Physa Gyrina ◽  
History Of

A cause of swimmer's itch in the lower Ottawa River is Trichobilharzia cameroni sp. nov. Its life cycle has been completed experimentally in laboratory-bred snails and in canaries and ducks, and the various stages are described. The eggs are spindle-shaped. The sporocysts are colorless and tubular. Mother sporocysts become mature in about a week. The younger daughter sporocyst is provided with spines on the anterior end and becomes mature in about three weeks. The development in the snail requires from 28 to 35 days. A few cercariae were found to live for up to 14 days at 50 °C., although their life at 16° to 18 °C. was about four days. Cercariae kept at room temperature for 60 to 72 hr. were found infective. The adults become mature in canaries and pass eggs in about 12 to 14 days. Physa gyrina is the species of snail naturally infected. It was found in one case giving off cercariae for five months after being kept in the laboratory. Domestic ducks were found to become infected until they were at least four months old, with the parasites developing to maturity in due course; no experiments were made with older ducks. Furthermore, miracidia were still recovered from the faeces four months after the duck had been experimentally infected, and it is suggested that migratory birds are the source of the local infection.

Memoirs: An Account of Amoeba Discoides; its Culture and Life History

1938 ◽  
Vol s2-80 (319) ◽  
pp. 459-478
Author(s):  
CATHERINE HAYES
Keyword(s):  
Life History ◽  
Life Cycle ◽  
Amoeba Proteus ◽  
Tropical Fish ◽  
Free Living ◽  
Free Living Amoeba ◽  
College Laboratory ◽  
Petri Dishes ◽  
Fish Tanks

1. A large free-living amoeba found by Mr. Harry Watkinson in the tropical fish tanks of Mr. Albert Sutcliffe of Grimsby has been identified as Amoeba discoides (Schaeffer, 1916) = Metachaos discoides (Schaeffer, 1926). 2. From the inoculation material obtained from these tanks Amoeba discoides has been successfully cultivated in the Notre Dame Training College Laboratory by a technique similar to that used for the cultivation of Amoeba proteus: wheat being the pabulum employed. In contrast to what obtains in the cultivation of Amoeba proteus , however, Amoeba discoides flourishes more luxuriantly in shallow Petri dishes, than in deeper troughs. 3. The nucleus in the resting and dividing stages is described; division is amitotic. 4. The more important cytoplasmic contents, including nutritive spheres, and crystals are likewise described. 5. The life-history has been worked out. The adult amoeba becomes an agamont giving rise to agametes which eventually grow into adult amoebae, the life-cycle occupying roughly about four months. 6. Descriptions of the nucleus of the newly hatched and developing amoebae are deferred. I wish to offer my sincerest thanks to Professor Graham Kerr under whom this work was begun, and who has continued from afar to watch over it with ever kindly interest and encouragement and who has read the paper in typescript. My thanks are also extended to Professor Hindle, under whom the work was completed, for his kind advice and for reading the paper in typescript. In conclusion I would like to express my appreciation of her skill and of the care and trouble bestowed by Miss Brown Kelly in the execution of the original drawing of fig. 1, PI. 31.

Outbreak and life cycle of the hook tip moth, Deroca inconclusa (Walker,1856) (Lepidoptera: Drepanidae) on Himalayan Dogwood, Cornus capitata Wall. ex Roxb. (Cornaceae) in Garhwal region of Western Himalaya, India

ENTOMON ◽  
2020 ◽  
Vol 45 (4) ◽  
pp. 311-316
Author(s):  
Arun Pratap Singh ◽  
Gaurav Chand Ramola
Keyword(s):  
Life History ◽  
Life Cycle ◽  
Western Himalaya ◽  
Forest Division ◽  
Reserve Forest ◽  
Garhwal Region ◽  
First Time

During the course of survey carried out in Chakrata hills (Chakrata Forest Division, Dehradun district, Uttarakhand (Western Himalaya), sporadic infestation by the hook tip moth, Deroca inconclusa (Walker,1856) (Lepidoptera: Drepanidae : Drepaninae) was recorded on Cornus capitata Wall. ex Roxb. trees in Chakrata Reserve Forest at several locations. Outbreak of the hook tip moth is being reported for the first time from this region along with its life history on C. capitata from the Garhwal region of the Western Himalaya.

scholarly journals Endocrine Control of Life-Cycle Stages: A Constraint on Response to the Environment?

The Condor ◽  
2000 ◽  
Vol 102 (1) ◽  
pp. 35-51 ◽  
Author(s):  
Jerry D. Jacobs ◽  
John C. Wingfield
Keyword(s):  
Life History ◽  
Life Cycle ◽  
Control Systems ◽  
Life Cycles ◽  
Environmental Cues ◽  
Endocrine Control ◽  
Theoretical Approaches ◽  
Life Cycle Stages ◽  
Wide Range ◽  
Breeding Seasons

Abstract Most organisms live in seasonal environments that fluctuate on a predictable schedule and sometimes unpredictably. Individuals must, therefore, adjust so as to maximize their survival and reproductive success over a wide range of environmental conditions. In birds, as in other vertebrates, endocrine secretions regulate morphological, physiological, and behavioral changes in anticipation of future events. The individual thus prepares for predictable fluctuations in its environment by changing life-cycle stages. We have applied finite-state machine theory to define and compare different life-history cycles. The ability of birds to respond to predictable and unpredictable regimes of environmental variation may be constrained by the adaptability of their endocrine control systems. We have applied several theoretical approaches to natural history data of birds to compare the complexity of life cycles, the degree of plasticity of timing of stages within the cycle, and to determine whether endocrine control mechanisms influence the way birds respond to their environments. The interactions of environmental cues on the timing of life-history stages are not uniform in all populations. Taking the reproductive life-history stage as an example, arctic birds that have short breeding seasons in severe environments appear to use one reliable environmental cue to time reproduction and they ignore other factors. Birds having longer breeding seasons exhibit greater plasticity of onset and termination and appear to integrate several environmental cues. Theoretical approaches may allow us to predict how individuals respond to their environment at the proximate level and, conversely, predict how constraints imposed by endocrine control systems may limit the complexity of life cycles.

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