Spawning Mode and Reproductive Output of the Tropical Cephalopod Idiosepius pygmaeus

1993 ◽  
Vol 50 (1) ◽  
pp. 20-28 ◽  
Author(s):  
Andrew R. Lewis ◽  
J. Howard Choat
Keyword(s):  
Body Weight ◽  
Egg Size ◽  
Reproductive Output ◽  
Reproductive Potential ◽  
Adult Life ◽  
Somatic Growth ◽  
Egg Laying ◽  
Adult Life Span ◽  
Adult Weight ◽  
Food Stress

Reproductive biology of the tropical sepioid cephalopod Idiosepius pygmaeus was investigated in wild specimens and in individuals maintained in aquaria through the adult life span. This species produced multiple egg batches over 80% of the observable adult weight range, indicating a coordination of reproductive and somatic growth. Reproductive output was consistent within, but variable between, individuals. Oocyte synthesis and maturation occur continuously after sexual maturation has been reached. Senescence and death are not related to an exhaustion of reproductive potential. On average, captive female I. pygmaeus with access to unlimited food produced 640 eggs in 11 batches over 18 d. When reproductive output was expressed as a ratio of dry female body weight, on average, specimens had incorporated five times their body weight into eggs and egg coatings. Under food stress, captive specimens laid fewer eggs but maintained egg size and periodicity of egg laying. Food stress had no effect on either laying duration or weight at death. This study provides further evidence that terminal spawning modes are not ubiquitous amongst cephalopods.

scholarly journals Reproductive traits of the gray ratsnake Ptyas korros from three geographically distinct populations

2012 ◽  
Vol 58 (6) ◽  
pp. 820-827 ◽  
Author(s):  
Long-Hui Lin ◽  
Fei Mao ◽  
Ce Chen ◽  
Xiang Ji
Keyword(s):  
Clutch Size ◽  
Egg Size ◽  
Reproductive Output ◽  
Reproductive Traits ◽  
Egg Laying ◽  
Laying Date ◽  
Egg Mass ◽  
Size Number ◽  
Female Reproductive Traits ◽  
Clutch Mass

Abstract We collected gravid gray rat snakes Ptyas korros from three geographically distinct populations in China, Chenzhou (CZ), Jiangshan (JS) and Dinghai (DH), to study geographical variation in female reproductive traits. Egg-laying dates differed among the three populations such that at the most northern latitude egg-laying was latest, and earliest at the most southern lati-tutde. Clutch size, clutch mass, egg mass, egg shape, within clutch variability in egg sizes and relative clutch mass differed among the three populations, whereas post-oviposition body mass did not. Except for egg-laying date, none of the traits examined varied in a geographically continuous trend. CZ and DH females, although separated by a distance of approximately 1100 km as the crow flies, were similar in nearly all traits examined. JS females were distinguished from CZ and DH females by their higher fecundity (clutch size), greater reproductive output (clutch mass) and more rounded eggs. Our data do not validate the prediction that larger offspring should be produced in colder localities. The absence of an egg size-number trade-off in each of the three populations presumably suggests that P. korros is among species where eggs are well optimized for size within a population.

scholarly journals The Effects of Temperature and of Egg-Laying on the Longevity of Drosophila Subobscura

1958 ◽  
Vol 35 (4) ◽  
pp. 832-842 ◽  
Author(s):  
J. MAYNARD SMITH
Keyword(s):  
Young Adult ◽  
Survival Time ◽  
Sharp Increase ◽  
Adult Life ◽  
Egg Laying ◽  
Drosophila Subobscura ◽  
Partial Regression ◽  
Adult Life Span ◽  
Prolongation Of Life ◽  
Effects Of Temperature

1. The adult life span of Drosophila subobscura has been measured at temperatures varying from 20° to 33° C. A sharp increase in the slope of the curve of log survival time against temperature occurs at temperatures above 31° C. 2. Changes which occur in individuals at 33° C. or above are reversible, at least in part, at 20° C.; but changes occurring at 30·5° C. are irreversible in the sense that the total survival time at 30·5° C. is not increased by intervening periods at 20° C. 3. Exposure of young adult flies to 30·5° C. for a period of about half their expectation of life at that temperature significantly increases the further expectation of life of females at 20° C. but does not alter the expectation of life of males. Such exposure causes a partial regression of the ovaries of females, a permanent change in their behaviour and a reduction in their rate of egg-laying; exposure does not alter the behaviour or seriously reduce the fertility of males. 4. ‘Ovariless’ females and virgin females live for significantly longer than do normal mated females. The expectation of life of ‘ovariless’ females at 20° C. is not altered by exposure to 30·5° C. It is concluded that egg-laying accelerates the ageing of females at 20° C., and that the prolongation of life of females exposed to 30·5° C. is due to the reduction in the rate at which such females subsequently lay eggs.

Biology of pulse beetle, Callosobruchus maculatus (F.) and its response to botanicals in stored pigeonpea, Cajanus cajan (L.) grains

2017 ◽  
Author(s):  
Rupesh Sharma ◽  
Renu Devi ◽  
Sunita Yadav ◽  
Poonam Godara
Keyword(s):  
Callosobruchus Maculatus ◽  
Adult Life ◽  
Egg Laying ◽  
Mustard Oil ◽  
Seed Kernel ◽  
Neem Oil ◽  
Groundnut Oil ◽  
Adult Life Span ◽  
Seed Damage ◽  
Pulse Beetle

Biology of pulse beetle (Callosobruchus maculatus F.) was studied on pigeonpea grains during 2014-15 in laboratory conditions. The adult beetle was oval in shape and reddish-brown in colour, with dark stripes on each side of dorsal abdomen with average fecundity of 74.8±1.8 eggs per female. The average incubation period was 4.2±0.2 days with hatching 98.2±0.3 percent. Average larval-pupal period, oviposition, post-oviposition period, total life period and adult life span were 21.3±0.3, 8.2±0.5, 2.8±0.5, 33.3 ±2.4 and 12.0±2.1 days, respectively. The effect of nine botanicals viz., neem oil, mustard oil, groundnut oil, turmeric powder and their mixture and surface protectants viz., neem seed kernel powder, saw dust, sand, dung cake ash and wheat husk were used on pigeonpea seed against Callosobruchus maculatus. The highest mortality (84-100%) was observed by neem oil @ 10ml/kg and lowest (3.33%) by turmeric powder @ 3.5g/kg seeds, after 135 days of storage. Neem oil @ 10ml/kg was completely inhibited the oviposition, adult emergence and seed damage. All the oils and inert materials prevented egg laying, reduced population build up of beetles and minimized the seed damage as compare to control.

Clutch size and egg size of spruce grouse in relation to spring diet, food supply, and endogenous reserves

1989 ◽  
Vol 67 (4) ◽  
pp. 969-980 ◽  
Author(s):  
Brian J. Naylor ◽  
James F. Bendell
Keyword(s):  
Body Weight ◽  
Clutch Size ◽  
Food Supply ◽  
Crude Protein ◽  
Egg Size ◽  
Follicular Development ◽  
Egg Laying ◽  
High Rate ◽  
Large Clutch ◽  
Endogenous Reserves

We examined the hypothesis that female spruce grouse (Dendragapus canadensis) rely entirely on their spring diet or endogenous reserves for the nutrients required for clutch formation. Spring food habits of 40 radio-tagged hens were documented by direct observation (21 262 min) during the period encompassing oviducal recrudescence, follicular development, and egg laying (late April – late May 1984 – 1986) and compared with clutch size and mean egg weight. Hens consumed conifer foliage, flowers, fruits, and foliage of ground plants, grit, and arthropods. Compared with their prebreeding diet, foods preferred in spring were rich in protein and P, but not necessarily Ca. Large clutch size was associated with a high rate of intake of the two most preferred foods, flowers of trailing arbutus (Epigaea repens) and spore capsules of Polytrichum mosses, and crude protein, P, and Ca, but was not related to the size of hens (body weight) or the size of endogenous reserves (scaled body weight). Egg size was not associated with spring diet or the size of endogenous reserves, but appeared to be related to the size of hens. Rate of intake of arbutus flowers and moss capsules was correlated with their availability on territories, suggesting that clutch size might have been proximately limited by food supply. However, rough estimates of nutrient intake suggested that the spring diet provided only about 60% of the protein and 45% of the Ca needed for clutch formation. Consequently, hens appeared to rely on both their spring diet and stored reserves for the nutrients required for clutch formation.

scholarly journals Increased production of mitochondrial reactive oxygen species and reduced adult life span in an insecticide-resistant strain of Anopheles gambiae

2014 ◽  
Vol 104 (3) ◽  
pp. 323-333 ◽  
Author(s):  
D. Otali ◽  
R.J. Novak ◽  
W. Wan ◽  
S. Bu ◽  
D.R. Moellering ◽  
...  
Keyword(s):  
Body Weight ◽  
Energy Metabolism ◽  
Life Span ◽  
Adult Life ◽  
Developmental Time ◽  
The Body ◽  
Susceptible Strain ◽  
Adult Survival ◽  
Adult Life Span ◽  
Adult Females

AbstractControl of the malaria vector An. gambiae is still largely obtained through chemical intervention using pyrethroids, such as permethrin. However, strains of An. gambiae that are resistant to the toxic effects of pyrethroids have become widespread in several endemic areas over the last decade. The objective of this study was to assess differences in five life-history traits (larval developmental time and the body weight, fecundity, hatch rate, and longevity of adult females) and energy metabolism between a strain of An. gambiae that is resistant to permethrin (RSP), due to knockdown resistance and enhanced metabolic detoxification, and a permethrin susceptible strain reared under laboratory conditions. We also quantified the expression levels of five antioxidant enzyme genes: GSTe3, CAT, GPXH1, SOD1, and SOD2. We found that the RSP strain had a longer developmental time than the susceptible strain. Additionally, RSP adult females had higher wet body weight and increased water and glycogen levels. Compared to permethrin susceptible females, RSP females displayed reduced metabolic rate and mitochondrial coupling efficiency and higher mitochondrial ROS production. Furthermore, despite higher levels of GSTe3 and CAT transcripts, RSP females had a shorter adult life span than susceptible females. Collectively, these results suggest that permethrin resistance alleles might affect energy metabolism, oxidative stress, and adult survival of An. gambiae. However, because the strains used in this study differ in their genetic backgrounds, the results need to be interpreted with caution and replicated in other strains to have significant implications for malaria transmission and vector control.

Interdisciplinary Adult Life Span Learning (Really!)

1996 ◽  
Vol 41 (6) ◽  
pp. 590-591
Author(s):  
Barbara R. Bjorklund
Keyword(s):  
Life Span ◽  
Adult Life ◽  
Adult Life Span

Emotion experience and expression across the adult life span: Insights from a multimodal assessment study.

2006 ◽  
Vol 21 (2) ◽  
pp. 303-317 ◽  
Author(s):  
Carol Magai ◽  
Nathan S. Consedine ◽  
Yulia S. Krivoshekova ◽  
Elizabeth Kudadjie-Gyamfi ◽  
Renee McPherson
Keyword(s):  
Life Span ◽  
Adult Life ◽  
Adult Life Span ◽  
Multimodal Assessment ◽  
Emotion Experience ◽  
Assessment Study

Interchannel Relationships for Emotional Perception Across the Adult Life Span

2008 ◽  
Author(s):  
Katie Finley ◽  
Joan C. Borod ◽  
Adam Brickman ◽  
J. M. Schmidt ◽  
Stephanie Assuras ◽  
...  
Keyword(s):  
Life Span ◽  
Adult Life ◽  
Adult Life Span ◽  
Emotional Perception

Modeling Spoken Discourse Comprehension Across the Adult Life Span

2008 ◽  
Author(s):  
Sandra Hale ◽  
Mitchell S. Sommers ◽  
Joel Myerson ◽  
Nancy Tye-Murray ◽  
Nathan Rose ◽  
...  
Keyword(s):  
Life Span ◽  
Adult Life ◽  
Discourse Comprehension ◽  
Adult Life Span ◽  
Spoken Discourse

Decoy effects in preferential choice across the adult life span

2006 ◽  
Author(s):  
Mark E. Faust ◽  
Kristi S. Multhaup ◽  
Patricia A. Brooks ◽  
Sarah Frey ◽  
Blair Hicks ◽  
...  
Keyword(s):  
Life Span ◽  
Adult Life ◽  
Adult Life Span ◽  
Preferential Choice ◽  
Decoy Effects
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