Locomotor impairment and defense in gravid lizards (Eumeces laticeps): behavioral shift in activity may offset costs of reproduction in an active forager

1990 ◽  
Vol 27 (3) ◽  
pp. 153-157 ◽  
Author(s):  
William E. Cooper ◽  
Laurie J. Vitt ◽  
Richard Hedges ◽  
Raymond B. Huey
Keyword(s):  
Costs Of Reproduction ◽  
Locomotor Impairment ◽  
Eumeces Laticeps ◽  
Active Forager

A West Indian Midwife’s Tale

2017 ◽  
Author(s):  
Katherine Paugh
Keyword(s):  
Population Growth ◽  
Family Life ◽  
West Indian ◽  
Wage Labor ◽  
British Government ◽  
Costs Of Reproduction ◽  
Radical Reform ◽  
Registry System ◽  
Sugar Market ◽  
The Caribbean

The abolition of the Atlantic slave trade by the British government in 1807 was prompted by a confluence of geopolitical developments and concerns about reproduction. Shifts in the Atlantic world sugar economy had led to a glut on the British sugar market, and boosting production was therefore less of an economic concern than safeguarding reproduction. After 1807, demographic and financial calculations regarding the future of the plantation system intensified with the institution of a registry system designed to track slave populations. By 1823, British politicians, both abolitionists and West Indian planters, agreed to further radical reform: they hoped that encouraging Christian marital mores would finally bring about economically beneficial population growth. Acts legalizing Afro-Caribbean marriage were subsequently passed throughout the Caribbean. The outcome of this new emphasis on family life was ironic: as slavery gave way to wage labor, the costs of reproduction were shifted to Afro-Caribbean parents.

scholarly journals Aerobic fitness is a potential crucial factor in protecting paralympic athletes with locomotor impairments from atherosclerotic cardiovascular risk

2020 ◽  
Author(s):  
Marco Bernardi ◽  
Silvio Romano ◽  
Maria Rosaria Squeo ◽  
Emanuele Guerra ◽  
Paolo Emilio Adami ◽  
...  
Keyword(s):  
Risk Factors ◽  
Cardiovascular Risk ◽  
Aerobic Fitness ◽  
Health Conditions ◽  
Limb Amputation ◽  
Atherosclerotic Cardiovascular Disease ◽  
Cord Injury ◽  
Sport Type ◽  
Locomotor Impairment ◽  
Prevalence Of Obesity

Abstract Purpose To test the hypothesis that aerobic fitness is inversely related to the risk of atherosclerotic cardiovascular disease (ACVD) in athletes with locomotor impairments deriving from health conditions, such as spinal cord injury (SCI), lower limb amputation, cerebral palsy, poliomyelitis, and other health conditions different from the previous ones. Methods A total of 68 male athletes who competed in either summer or winter Paralympic games were divided in two health conditions groups (35 with SCI, mean age 37.2 ± 8.0 years, and 33 with different health conditions, mean age 37.8 ± 9.9 years) and in four sport type groups (skill, power, intermittent—mixed metabolism—and endurance). They were evaluated through anthropometric and blood pressure measurements, laboratory blood tests, and graded cardiopulmonary maximal arm cranking exercise test, with oxygen uptake peak (VO2peak) measurement. Cardiovascular risk profile was assessed in each athlete. Results The prevalence of ACVD-risk factors in the overall population was 20.6% for hypertension; 47% and 55.9% for high values of total and LDL cholesterol, respectively; 22.1% for reduce glucose tolerance; and 8.8% for obesity. No difference was found between athletes with and without SCI, while the prevalence of obesity was significantly higher in those practicing skill sports (22.7%, p = 0.035), which was the sport type group with Paralympic athletes with the lowest VO2peak (22.5 ± 5.70 ml kg−1 min−1). VO2peak was lower in athletes with SCI than those with different health conditions (28.6 ± 10.0 vs 33.6 ± 8.9 ml kg−1 min−1p = 0.03), and in those with 3–4 risk factors (19.09 ± 5.34 ml kg−1 min−1) than those with 2 risk factors (27.1 ± 5.50 ml kg−1 min−1), 1 risk factor (31.6 ± 8.55 ml kg−1 min−1), or none (36.4 ± 8.76 ml kg−1 min−1) (p < 0.001). Conclusions The present study suggests that having higher VO2peak seems to offer greater protection against ACVD in individuals with a locomotor impairment. Prescribing physical exercise at an intensity similar to that of endurance and intermittent sports should become a fundamental tool to promote health among people with a locomotor impairment.

scholarly journals The physiological costs of reproduction in small mammals

2007 ◽  
Vol 363 (1490) ◽  
pp. 375-398 ◽  
Author(s):  
John R Speakman
Keyword(s):  
Life History ◽  
Small Mammals ◽  
Morphological Changes ◽  
Life History Evolution ◽  
Indirect Costs ◽  
Direct Costs ◽  
Costs Of Reproduction ◽  
Dominant Component ◽  
Trade Offs ◽  
Almost All

Life-history trade-offs between components of fitness arise because reproduction entails both gains and costs. Costs of reproduction can be divided into ecological and physiological costs. The latter have been rarely studied yet are probably a dominant component of the effect. A deeper understanding of life-history evolution will only come about once these physiological costs are better understood. Physiological costs may be direct or indirect. Direct costs include the energy and nutrient demands of the reproductive event, and the morphological changes that are necessary to facilitate achieving these demands. Indirect costs may be optional ‘compensatory costs’ whereby the animal chooses to reduce investment in some other aspect of its physiology to maximize the input of resource to reproduction. Such costs may be distinguished from consequential costs that are an inescapable consequence of the reproductive event. In small mammals, the direct costs of reproduction involve increased energy, protein and calcium demands during pregnancy, but most particularly during lactation. Organ remodelling is necessary to achieve the high demands of lactation and involves growth of the alimentary tract and associated organs such as the liver and pancreas. Compensatory indirect costs include reductions in thermogenesis, immune function and physical activity. Obligatory consequential costs include hyperthermia, bone loss, disruption of sleep patterns and oxidative stress. This is unlikely to be a complete list. Our knowledge of these physiological costs is currently at best described as rudimentary. For some, we do not even know whether they are compensatory or obligatory. For almost all of them, we have no idea of exact mechanisms or how these costs translate into fitness trade-offs.

Reproductive effort and costs of reproduction in female European ground squirrels

Oecologia ◽  
1999 ◽  
Vol 121 (1) ◽  
pp. 19-24 ◽  
Author(s):  
Susanne Huber ◽  
Eva Millesi ◽  
Manfred Walzl ◽  
John Dittami ◽  
Walter Arnold
Keyword(s):  
Reproductive Effort ◽  
Ground Squirrels ◽  
Costs Of Reproduction

Flux hydriques et métabolisme énergétique dans un peuplement de Lacertidés des îles Kerkennah (Tunisie)

1988 ◽  
Vol 66 (3) ◽  
pp. 555-561 ◽  
Author(s):  
Roland Vernet ◽  
Claude Grenot ◽  
Saïd Nouira
Keyword(s):  
Energy Expenditure ◽  
Daily Activity ◽  
Water Flux ◽  
Sympatric Species ◽  
Doubly Labeled Water ◽  
Daily Energy Expenditure ◽  
Water Turnover ◽  
Semiarid Environment ◽  
Daily Energy ◽  
Active Forager

Water flux and daily energy expenditure were measured with doubly labeled water (3HH18O) in two insectivorous sympatric species of Lacertidae of Kerkennah islands (Tunisia), Eremias olivieri (mean body mass: 1.1 g) and Acanthodactylus pardalis (4.5 g) in a semiarid environment. Water turnover and field metabolic rate of Eremias olivieri (174 μL H2O g−1 d−1 and 250 J g−1 d−1) were, respectively, 2.5 and 5 times higher than those of Acanthodactylus pardalis (70 μL H2O g−1 d−1 and 52 J g−1 d−1). The water turnover of Eremias olivieri is one of the highest known among insectivorous lizards, and the daily energy expenditure of Acanthodactylus pardalis one of the lowest. The most plausible explanations are the differences in the size of the prey eaten by each species at this time of the season and in the duration of daily activity; the daily activity of Acanthodactylus pardalis is short (4.5 h d−1) although it is a sit-and-wait predator, whereas Eremias olivieri is active regularly every day for a longer period (7.5 h d−1) although it is an active forager. The high values of water turnover in Eremias olivieri suggest that food is not the only source of water for lizards in this particular insular environment.

scholarly journals Cornel Iridoid Glycoside Improves Locomotor Impairment and Decreases Spinal Cord Damage in Rats

2016 ◽  
Vol 2016 ◽  
pp. 1-12
Author(s):  
Wen-jing Tang ◽  
Deng-lei Ma ◽  
Cui-cui Yang ◽  
Li Zhang ◽  
Ya-li Li ◽  
...  
Keyword(s):  
Spinal Cord ◽  
Rating Scale ◽  
Iridoid Glycoside ◽  
Neurotrophin Receptor ◽  
Intragastric Administration ◽  
P75 Neurotrophin Receptor ◽  
Lesion Site ◽  
Cord Injury ◽  
Locomotor Impairment ◽  
Cornel Iridoid Glycoside

Purpose. This study was to investigate the effects of cornel iridoid glycoside (CIG) on spinal cord injury (SCI) in rats. Methods. The thoracic cord (at T9) of rats was injured by clip compression for 30 sec. Locomotor function was assessed using the Basso, Beattie, and Bresnahan (BBB) rating scale. Neuroanatomic stereological parameters as well as Nogo-A, p75 neurotrophin receptor (p75NTR), and ROCKII expression were measured by histological processing, immunohistochemistry, and stereological analyses. The axons passing through the lesion site were detected by BDA tracing. Results. Intragastric administration of CIG (60 and 180 mg/kg) improved the locomotor impairment at 10, 17, 24, and 31 days post-injury (dpi) compared with untreated SCI model rats. CIG treatment decreased the volume of the lesion epicenter (LEp) and increased the volume of spared tissue and the number of surviving neurons in the injured spinal cord at 31 dpi. CIG promoted the growth of BDA-positive axons and their passage through the lesion site and decreased the expression of Nogo-A, p75NTR, and ROCKII both in and around the LEp. Conclusion. CIG improved the locomotor impairment, decreased tissue damage, and downregulated the myelin-associated inhibition signaling pathway in SCI rats. The results suggest that CIG may be beneficial for SCI therapy.

Deferred agonistic behavior in a long-lived scincid lizard Eumeces laticeps

Oecologia ◽  
1987 ◽  
Vol 72 (3) ◽  
pp. 321-326 ◽  
Author(s):  
W. E. Cooper ◽  
L. J. Vitt
Keyword(s):  
Agonistic Behavior ◽  
Eumeces Laticeps

The costs of reproduction in tree swallows (Tachycineta bicolor)

1991 ◽  
Vol 69 (10) ◽  
pp. 2540-2547 ◽  
Author(s):  
Nathaniel T. Wheelwright ◽  
Joanna Leary ◽  
Caragh Fitzgerald
Keyword(s):  
Life History ◽  
Clutch Size ◽  
Brood Size ◽  
Life History Theory ◽  
Tachycineta Bicolor ◽  
Laying Date ◽  
Tree Swallows ◽  
Costs Of Reproduction ◽  
Return Rates ◽  
Trade Offs

We investigated the effect of brood size on nestling growth and survival, parental survival, and future fecundity in tree swallows (Tachycineta bicolor) over a 4-year period (1987–1990) in an effort to understand whether reproductive trade-offs limit clutch size in birds. In addition to examining naturally varying brood sizes in a population on Kent Island, New Brunswick, Canada, we experimentally modified brood sizes, increasing or decreasing the reproductive burdens of females by two offspring. Unlike previous studies, broods of the same females were enlarged or reduced in up to 3 successive years in a search for evidence of cumulative costs of reproduction that might go undetected by a single brood manipulation. Neither observation nor experiment supported the existence of a trade-off between offspring quality and quantity, in contrast with the predictions of life-history theory. Nestling wing length, mass, and tarsus length were unrelated to brood size. Although differences between means were in the direction predicted, few differences were statistically significant, despite large sample sizes. Nestlings from small broods were no more likely to return as breeding adults than nestlings from large broods, but return rates of both groups were very low. Parental return rates were also independent of brood size, and there was no evidence of a negative effect of brood size on future fecundity (laying date, clutch size). Reproductive success, nestling size, and survival did not differ between treatments for females whose broods were manipulated in successive years. Within the range of brood sizes observed in this study, the life-history costs of feeding one or two additional nestlings in tree swallows appear to be slight and cannot explain observed clutch sizes. Costs not measured in this study, such as the production of eggs or postfledging parental care, may be more important in limiting clutch size in birds.

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