scholarly journals Honest signaling in mouse lemur vocalizations?

2021 ◽  
Author(s):  
Claudia Fichtel ◽  
Peter M. Kappeler ◽  
Martine Perret ◽  
Elise Huchard ◽  
Pierre-Yves Henry
Keyword(s):  
Social Interactions ◽  
Body Mass ◽  
Honest Signaling ◽  
Acoustic Features ◽  
Motivational State ◽  
Structural Rules ◽  
Honest Signals ◽  
Animal Vocalizations ◽  
Dietary Regime ◽  
Ad Libitum

AbstractAnimal vocalizations may provide information about a sender’s condition or motivational state and, hence, mediate social interactions. In this study, we examined whether vocalizations of gray mouse lemurs (Microcebus murinus) emitted in aggressive contexts (grunts, tsaks) co-vary with physical condition, which would underly and indicate honest signaling. We recorded calls from captive individuals that were subjected to a caloric restricted (CR) or ad libitum (AL) diet, assuming that individuals on an ad libitum dietary regime were in better condition. We analyzed 828 grunts produced by seven CR and nine AL individuals and 270 tsaks by eight CR and five AL individuals. Grunts consisted of two separate elements, with the 1st element having more energy in higher frequencies than the 2nd element. Body mass correlated negatively with acoustic features of grunts, and heavier individuals produced lower-frequency grunts. Acoustic features of grunts did not differ between sexes. Acoustic features of tsaks were predicted by neither body mass nor sex. However, tsaks produced by AL individuals were noisier than those of CR individuals. Hence, manipulation of body condition via dietary regimes affected acoustic features of calls given during aggression in different ways: acoustic features of grunts varied according to the rule of acoustic allometry, and can be considered as honest signals. Acoustic features of tsaks, however, varied according to motivational structural rules. Longitudinal studies are now indicated to examine whether intra-individual changes in body mass are also reflected in the acoustic structure of calls, allowing callers to signal more flexible variation in condition.

scholarly journals Stable eusociality via maternal manipulation when resistance is costless

2015 ◽  
Author(s):  
Mauricio González-Forero
Keyword(s):  
Mathematical Model ◽  
Resource Allocation ◽  
Maternal Care ◽  
Honest Signaling ◽  
Queen Pheromones ◽  
Honest Signals ◽  
Long Run ◽  
Maternal Manipulation ◽  
Selection For ◽  
Eusocial Species

In many eusocial species, queens use pheromones to influence offspring to express worker phenotypes. While evidence suggests that queen pheromones are honest signals of the queen's reproductive health, here I show that queen's honest signaling can result from ancestral maternal manipulation. I develop a mathematical model to study the coevolution of maternal manipulation, offspring resistance to manipulation, and maternal resource allocation. I assume that (1) maternal manipulation causes offspring to be workers against offspring's interests; (2) offspring can resist at no direct cost, as is thought to be the case with pheromonal manipulation; and (3) the mother chooses how much resource to allocate to fertility and maternal care. In the coevolution of these traits, I find that maternal care decreases, thereby increasing the benefit that offspring obtain from help, which in the long run eliminates selection for resistance. Consequently, ancestral maternal manipulation yields stable eusociality despite costless resistance. Additionally, ancestral manipulation in the long run becomes honest signaling that induces offspring to help. These results indicate that both eusociality and its commonly associated queen honest signaling can be likely to originate from ancestral manipulation.

scholarly journals Maternal stress during pregnancy causes sex-specific alterations in offspring memory performance, social interactions, indices of anxiety, and body mass

2011 ◽  
Vol 104 (2) ◽  
pp. 340-347 ◽  
Author(s):  
Kalynn M. Schulz ◽  
Jennifer N. Pearson ◽  
Eric W. Neeley ◽  
Ralph Berger ◽  
Sherry Leonard ◽  
...  
Keyword(s):  
Social Interactions ◽  
Body Mass ◽  
Maternal Stress ◽  
Memory Performance

Effect of acute nutritional deprivation on diaphragm structure and function in adolescent rats

1992 ◽  
Vol 73 (3) ◽  
pp. 974-978 ◽  
Author(s):  
M. I. Lewis ◽  
G. C. Sieck
Keyword(s):  
Body Mass ◽  
Muscle Fiber ◽  
Fiber Type ◽  
Structure And Function ◽  
Muscle Fiber Type ◽  
Medial Gastrocnemius ◽  
Diaphragm Muscle ◽  
Nutritional Deprivation ◽  
Ad Libitum ◽  
And Function

The influence of 90 h of acute nutritional deprivation (ND; water ad libitum only) on in vitro contractile and fatigue properties, muscle fiber type proportions, and cross-sectional areas (CSA) of the adolescent rat diaphragm was determined. Diaphragm muscle properties in the ND rats were compared with those in control rats (CTL; food and water ad libitum). Acute ND resulted in a 32% reduction in body mass, whereas the body mass of CTL rats increased by 29%. Acute ND resulted in a significant reduction in the mass of the diaphragm (costal, 36%; crural, 43%), soleus (36%), and medial gastrocnemius (45%) muscles. Isometric twitch characteristics of the diaphragm muscle (contraction and half-relaxation times) were prolonged in the ND animals. Peak twitch and maximum tetanic forces were unaffected by ND. Fatigue resistance of the diaphragm muscle was improved in ND animals. Diaphragm muscle fiber type proportions were similar in ND and CTL groups. The CSA of type I and II diaphragm muscle fibers were reduced by 22 and 40%, respectively, in ND animals compared with CTL. We conclude that, whereas an identical protocol of acute ND had no significant effects on diaphragm muscle structure and function in adult rats, adolescent animals exhibit significantly less nutritional reserve. These differences may be due to curtailment of the rapid anabolic rate in growing animals.

The Influence of Heat Acclimation and Hypohydration on Post-Weight-Loss Exercise Performance

2020 ◽  
Vol 15 (2) ◽  
pp. 213-221
Author(s):  
Oliver R. Barley ◽  
Dale W. Chapman ◽  
Georgios Mavropalias ◽  
Chris R. Abbiss
Keyword(s):  
Body Mass ◽  
Exercise Performance ◽  
Fluid Intake ◽  
Heat Acclimation ◽  
Hydration Status ◽  
Performance Variables ◽  
Pooled Data ◽  
Ad Libitum ◽  
Experimental Trials ◽  
Food And Fluid Intake

Purpose: To examine the influence of fluid intake on heat acclimation and the subsequent effects on exercise performance following acute hypohydration. Methods: Participants were randomly assigned to 1 of 2 groups, either able to consume water ad libitum (n = 10; age 23 [3] y, height 1.81 [0.09] m, body mass 87 [13] kg; HAW) or not allowed fluid (n = 10; age 26 [5] y, height 1.76 [0.05] m, body mass 79 [10] kg; HANW) throughout 12 × 1.5-h passive heat-acclimation sessions. Experimental trials were completed on 2 occasions before (2 baseline trials) and 1 following the heat-acclimation sessions. These sessions involved 3 h of passive heating (45°C, 38% relative humidity) to induce hypohydration followed by 3 h of ad libitum food and fluid intake after which participants performed a repeat sled-push test to assess physical performance. Urine and blood samples were collected before, immediately, and 3 h following hypohydration to assess hydration status. Mood was also assessed at the same time points. Results: No meaningful differences in physiological or performance variables were observed between HANW and HAW at any time point. Using pooled data, mean sprint speed was significantly (P < .001) faster following heat acclimation (4.6 [0.7] s compared with 5.1 [0.8] s). Furthermore, heat acclimation appeared to improve mood following hypohydration. Conclusions: Results suggest that passive heat-acclimation protocols may be effective at improving short-duration repeat-effort performance following acute hypohydration.

Exercise and body composition

1991 ◽  
Vol 70 (3) ◽  
pp. 994-997 ◽  
Author(s):  
G. B. Forbes
Keyword(s):  
Young Adults ◽  
Body Composition ◽  
Lean Body Mass ◽  
Body Mass ◽  
Body Fat ◽  
Training Programs ◽  
Published Data ◽  
Additional Information ◽  
Body Fat Content ◽  
Ad Libitum

We assessed changes in body composition in 41 young adults who engaged in various exercise and/or training programs on ad libitum diets. Most of those who gained weight sustained an increase in lean body mass (LBM), and most of those who lost weight lost LBM as well as fat. The change in LBM was directly related to the change in weight, with a regression slope of 0.500. An analysis of published data confirms these findings and, in concert with our data, provides the additional information that the magnitude of the change in body composition in exercising individuals is influenced by body fat content, just as it is for nonexercising individuals.

scholarly journals Ad Libitum Fluid Consumption via Self- or External Administration

2015 ◽  
Vol 50 (1) ◽  
pp. 51-58 ◽  
Author(s):  
Susan W. Yeargin ◽  
Megan E. Finn ◽  
Lindsey E. Eberman ◽  
Matthew J. Gage ◽  
Brendon P. McDermott ◽  
...  
Keyword(s):  
Body Mass ◽  
Repeated Measures ◽  
Athletic Trainers ◽  
Urine Osmolality ◽  
Time Frame ◽  
Hydration Status ◽  
Fluid Consumption ◽  
Self Administration ◽  
Average Volume ◽  
Ad Libitum

Context: During team athletic events, athletic trainers commonly provide fluids with water bottles. When a limited number of water bottles exist, various techniques are used to deliver fluids. Objective: To determine whether fluid delivered via water-bottle administration influenced fluid consumption and hydration status. Design: Crossover study. Setting: Outdoor field (22.2°C ± 3.5°C). Patients or Other Participants: Nineteen participants (14 men, 5 women, age = 30 ± 10 years, height = 176 ± 8 cm, mass = 72.5 ± 10 kg) were recruited from the university and local running clubs. Intervention(s): The independent variable was fluid delivery with 3 levels: self-administration with mouth-to-bottle direct contact (SA-DC), self-administration with no contact between mouth and bottle (SA-NC), and external administration with no contact between the mouth and the bottle (EA-NC). Participants warmed up for 10 minutes before completing 5 exercise stations, after which an ad libitum fluid break was given, for a total of 6 breaks. Main Outcome Measure(s): We measured the fluid variables of total volume consumed, total number of squirts, and average volume per squirt. Hydration status via urine osmolality and body-mass loss, and perceptual variables for thirst and fullness were recorded. We calculated repeated-measures analyses of variance to assess hydration status, fluid variables, and perceptual measures to analyze conditions across time. Results: The total volume consumed for EA-NC was lower than for SA-DC (P = .001) and SA-NC (P = .001). The total number of squirts for SA-DC was lower than for SA-NC (P = .009). The average volume per squirt for EA-NC was lower than for SA-DC (P = .020) and SA-NC (P = .009). Participants arrived (601.0 ± 21.3 mOsm/L) and remained (622.3 ± 38.3 mOsm/L) hydrated, with no difference between conditions (P = .544); however, the EA-NC condition lost more body mass than did the SA-DC condition (P = .001). There was no main effect for condition on thirst (P = .147) or fullness (P = .475). Conclusions: External administration of fluid decreased total volume consumed via a decreased average volume per squirt. The SA-DC method requires fewer squirts within a specific time frame. Fluid breaks every 15 minutes resulted in maintenance of euhydration; however, loss of body mass was influenced by fluid administration. Athletic trainers should avoid external administration to promote positive hydration behaviors. When fluid is self-administered, individual bottles may be the best clinical practice because more volume can be consumed per squirt.

scholarly journals Drinking to Thirst Versus Drinking Ad Libitum During Road Cycling

2014 ◽  
Vol 49 (5) ◽  
pp. 624-631 ◽  
Author(s):  
Lawrence E. Armstrong ◽  
Evan C. Johnson ◽  
Laura J. Kunces ◽  
Matthew S. Ganio ◽  
Daniel A. Judelson ◽  
...  
Keyword(s):  
Body Mass ◽  
Perceived Exertion ◽  
Fluid Intake ◽  
Thermal Sensation ◽  
Drinking Behavior ◽  
Total Fluid Intake ◽  
Finish Line ◽  
Road Cycling ◽  
Significant Difference ◽  
Ad Libitum

Context: The sensation of thirst is different from the complex behavior of drinking ad libitum. Rehydration recommendations to athletes differ, depending on the source, yet no previous researchers have systematically compared drinking to thirst (DTT) versus ad libitum drinking behavior (DAL). Objective: To compare 2 groups of trained cyclists (DTT and DAL) who had similar physical characteristics and training programs (P &gt; .05). The DTT group (n = 12, age = 47 ± 7 years) drank only when thirsty, whereas the DAL group (n = 12, age = 44 ± 7 years) consumed fluid ad libitum (ie, whenever and in whatever volume desired). Design: Cohort study. Setting: Road cycling (164 km) in the heat (36.1°C ± 6.5°C). Patients or Other Participants: Ultraendurance cyclists (4 women, 20 men). Intervention(s): We recorded measurements 1 day before the event, on event day before the start, at 3 roadside aid stations, at the finish line, and 1 day after the event. Main Outcome Measure(s): Body mass, urinary hydration indices, and food and fluids consumed. Results: No between-groups differences were seen on event day for total exercise time (DTT = 6.69 ± 0.89 hours, DAL = 6.66 ± 0.77 hours), urinary indices (specific gravity, color), body mass change (DTT = −2.22% ± 1.73%, DAL = −2.29% ± 1.62%), fluid intake (DTT = 5.63 ± 2.59 L/6.7 h, DAL = 6.04 ± 2.37 L/6.7 h), dietary energy intake, macronutrient intake, ratings of thirst (DTT start = 2 ± 1, DTT finish = 6 ± 1, DAL start = 2 ± 1, DAL finish = 6 ± 1), pain, perceived exertion, or thermal sensation. Total fluid intake on recovery day +1 was the primary significant difference (DAL = 5.13 ± 1.87 L/24 h, DTT = 3.13 ± 1.53 L/24 h, t18 = 2.59, P = .02). Conclusions: Observations on event day indicated that drinking to thirst and drinking ad libitum resulted in similar physiologic and perceptual outcomes. This suggests that specific instructions to “drink to thirst” were unnecessary. Indeed, if athletes drink ad libitum, they can focus on training and competition rather than being distracted by ongoing evaluation of thirst sensations.

scholarly journals Single-Arm 8-Week Ad Libitum Self-Prepared Paleo Diet Reduces Cardiometabolic Disease Risk Factors in Overweight Adults

2019 ◽  
pp. 155982761986615
Author(s):  
Melissa M. Markofski ◽  
Kristofer Jennings ◽  
Chad Dolan ◽  
Natalie A. Davies ◽  
Emily C. LaVoy ◽  
...  
Keyword(s):  
Risk Factors ◽  
Blood Pressure ◽  
Body Mass ◽  
Dietary Intervention ◽  
Disease Risk ◽  
Cardiometabolic Disease ◽  
Paleo Diet ◽  
Ad Libitum ◽  
Physically Inactive ◽  
Cardiometabolic Disease Risk

The paleo diet is popular among the general population due to promoted weight loss and disease prevention benefits. We examined the effectiveness of a self-administered paleo diet in improving cardiometabolic disease risk factors. Overweight, physically inactive but otherwise healthy adults (males = 4, females = 3, age 32.7 ± 4.9 years, body mass index [BMI] 29.4 ± 2.4 kg/m2) habitually eating a traditional Western diet (1853.4 ± 441.2 kcal; 34.0% carbohydrate; 41.4% fat; 19.2% protein) completed an ad libitum self-administered paleo diet for 8 weeks. Height, weight, blood pressure, and a fasting blood sample were collected pre– and post–paleo dietary intervention. Blood samples were analyzed for fasting cardiometabolic disease biomarkers—including brain-derived neurotropic factor (BDNF), fibroblast growth factor (FGF) 21, and leptin. After 8 weeks, body mass (−5.3 kg, P = .008), BMI (−1.7 kg/m2, P = .002), serum leptin (−56.2%, P = .012), serum FGF21 (−26.7%, P = .002), and serum BDNF (−25.8%, P = .045) significantly decreased. Systolic and diastolic blood pressure were unchanged following the paleo dietary intervention ( P > .05). Average energy intake (−412.6 kcal, P = .016) significantly decreased with the paleo dietary intervention mostly due to a reduction in carbohydrate consumption (−69.2 g; P = .003). An 8-week self-administered paleo dietary intervention was effective in improving cardiometabolic disease risk factors in a healthy, physically inactive overweight adult population.

Selected Contribution: Bone adaptation with aging and long-term caloric restriction in Fischer 344 × Brown-Norway F1-hybrid rats

2003 ◽  
Vol 95 (4) ◽  
pp. 1739-1745 ◽  
Author(s):  
Jeremy M. LaMothe ◽  
Russell T. Hepple ◽  
Ronald F. Zernicke
Keyword(s):  
Life Span ◽  
Caloric Restriction ◽  
Structural Properties ◽  
Body Mass ◽  
Bone Geometry ◽  
Bone Adaptation ◽  
Brown Norway ◽  
F1 Hybrid ◽  
Fischer 344 ◽  
Ad Libitum

Rodents are commonly used as models for human aging because of their relatively short life span, the ease of obtaining age-specific tissue samples, and lower cost. However, age-associated disease may confound inbred animal studies. For example, numerous physiologically significant lesions, such as chronic nephropathy, are more common in aged Fischer 344 (F344) rats than in other strains (Bronson RT, Genetic Effects of Aging, 1990). Conversely, F344 × Brown-Norway F1-hybrid (F344BN) rats, developed by the National Institute on Aging for aging research, live considerably longer and have fewer pathologies at any given age vs. inbred strains (Lipman RD, Chrisp CE, Hazzard DG, and Bronson RT, J Gerontol A Biol Sci Med Sci 51: 54-59, 1996). To our knowledge, there are no data regarding the effect of age on bone geometry and mechanics in this strain of rat. Furthermore, caloric restriction (CR) extends the mean and maximal life span of animals and significantly reduces age-associated disease but may have adverse consequences for bone growth and mechanics. Thus we investigated the effects of age and CR on bone geometry and mechanics in the axial and appendicular skeleton of F344 Brown-Norway rats. Ad libitum fed rats were assessed at 8 mo (young adult; n = 6), 28 mo (late middle age; n = 5), and 36 mo (senescence; n = 6). CR rats were assessed at 28 mo ( n = 6). Tibiae and the sixth lumbar vertebrae (L6) were dissected, scanned (micro-computed tomography) to determine geometry, and tested mechanically. From 8 to 36 mo, there were no significant changes in L6 geometry, and only the cross-sectional moment of inertia changed (increased) with the tibia. CR-induced body mass reductions accounted for changes in L6 load at proportional limit, maximal load, and stiffness (structural properties), but altered tibial structural properties were independent of body mass. In tibiae, geometric changes dominated alterations in structural properties. Those data demonstrated that, whereas aging in ad libitum-fed animals induced minor changes in bone mechanics, axial and appendicular bones were adversely influenced by CR in late-middle-aged animals in different manners.

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