Assessing the intensity of sexual selection on male body mass and antler length in roe deer Capreolus capreolus: is bigger better in a weakly dimorphic species?

Oikos ◽  
2010 ◽  
Vol 119 (9) ◽  
pp. 1484-1492 ◽  
Author(s):  
Cécile Vanpé ◽  
Jean-Michel Gaillard ◽  
Petter Kjellander ◽  
Olof Liberg ◽  
Daniel Delorme ◽  
...  
1996 ◽  
Vol 74 (2) ◽  
pp. 245-253 ◽  
Author(s):  
A. J. M. Hewison ◽  
J. M. Angibault ◽  
E. Bideau ◽  
J. P. Vincent ◽  
J. Boutin ◽  
...  

Patterns of growth and seasonal variation in body mass, kidney fat level, and bone marrow fat level were investigated in a roe deer population south of Paris. Size dimorphism was not apparent until the deer were 2 years of age, following a second period of rapid growth in males during spring–summer. No differences between the sexes in fat accumulation or in the periodicity of the annual fat cycle were observed. However, annual cycles of adult body mass were asynchronous between the sexes. Carcase mass was stable for much of the year, but one marked seasonal decline was observed in animals of each sex. For females (April–August) this reflected investment in late gestation and lactation, but among males (April–November) it was presumably linked to the costs of rutting. Contrary to reports for other ungulates, no over-winter decline in adult carcase mass, kidney fat level, or bone marrow fat level was observed, possibly because winters were mild. All four fat indices (kidney fat index, three bone-marrow fat indices) declined over spring–summer. This seasonal cyclicity does not match the energy requirements of reproductive activity, suggesting that the fat cycle is intrinsic, linked to seasonal metabolic variation in roe deer. We suggest that carcase mass is a more reliable index of condition in roe deer.


1997 ◽  
Vol 75 (9) ◽  
pp. 1532-1535 ◽  
Author(s):  
Janne Kotiaho ◽  
Rauno V. Alatalo ◽  
Johanna Mappes ◽  
Silja Parri

In the wolf spider Hygrolycosa rubrofasciata, males court females by drumming dry leaves with their abdomen. Females prefer to mate with the most actively drumming males, and courtship drumming activity is also positively correlated with male viability. However, body mass of the males seems to have only a minor, if any, effect on female choice or male viability. There is also no correlation between male body mass and courtship drumming activity. We studied the effect of body mass and courtship drumming activity on the outcome of agonistic encounters between male H. rubrofasciata. For this purpose, males and females were randomly placed in a plastic arena, where male courtship drumming activity and agonistic encounters were recorded. Large differences in body mass and drumming activity between two rivals seemed to independently increase the probability of the larger or more active males winning. We conclude that while courtship drumming activity affects the fighting success of the males, and body mass more so, male–male interactions may not be of major importance in sexual selection of H. rubrofasciata.


2006 ◽  
Vol 84 (10) ◽  
pp. 1505-1512 ◽  
Author(s):  
E. Raganella-Pelliccioni ◽  
L. Boitani ◽  
S. Toso

We investigated the effect of body mass, spring and summer total rainfall, birth period, and local population density on the survival of 130 roe deer ( Capreolus capreolus (L., 1758)) fawns captured over seven fawning seasons (1997–2003) and radio-monitored daily. We modelled survival using the program MARK, incorporating biological questions into different models, following a priori hypotheses. The best model was selected using Akaike’s information criterion. The population was surveyed by counts and estimates were obtained using mark–resight methods. Weekly survival of roe deer fawns exhibits a pseudo-threshold time trend. Probability of survival is low (0.33 ± 0.0046) in summer, increases (0.79 ± 0.0021) in fall, and approaches the highest value typical of adult survival (0.90 ± 0.00091 and 0.96 ± 0.00021 by the end of March and May, respectively) during early spring following birth. The final model predicts that survival of roe deer fawns is positively affected by total precipitation in spring and body mass under a pseudo-threshold time variation pattern. In contrast with other studies, we did not detect any effect of population density on survival of fawns. This study contributes to the scarce knowledge about the performance of roe deer populations in Mediterranean ecosystems, providing evidence that climate variables and individual characteristics shape the vital rates of roe deer populations.


2014 ◽  
Vol 281 (1790) ◽  
pp. 20140873 ◽  
Author(s):  
L. Debeffe ◽  
N. Morellet ◽  
N. Bonnot ◽  
J. M. Gaillard ◽  
B. Cargnelutti ◽  
...  

When individuals disperse, they modify the physical and social composition of their reproductive environment, potentially impacting their fitness. The choice an individual makes between dispersal and philopatry is thus critical, hence a better understanding of the mechanisms involved in the decision to leave the natal area is crucial. We explored how combinations of behavioural (exploration, mobility, activity and stress response) and morphological (body mass) traits measured prior to dispersal were linked to the subsequent dispersal decision in 77 roe deer Capreolus capreolus fawns. Using an unusually detailed multi-trait approach, we identified two independent behavioural continuums related to dispersal. First, a continuum of energetic expenditure contrasted individuals of low mobility, low variability in head activity and low body temperature with those that displayed opposite traits. Second, a continuum of neophobia contrasted individuals that explored more prior to dispersal and were more tolerant of capture with those that displayed opposite traits. While accounting for possible confounding effects of condition-dependence (body mass), we showed that future dispersers were less neophobic and had higher energetic budgets than future philopatric individuals, providing strong support for a dispersal syndrome in this species.


2010 ◽  
Vol 25 (1) ◽  
pp. 39-45 ◽  
Author(s):  
C. KIFFNER ◽  
C. LÖDIGE ◽  
M. ALINGS ◽  
T. VOR ◽  
F. RÜHE

2001 ◽  
Vol 79 (9) ◽  
pp. 1650-1660 ◽  
Author(s):  
Shane P Mahoney ◽  
John A Virgl ◽  
Kim Mawhinney

Phenotypic variation in body size and degree of sexual size dimorphism of North American black bears (Ursus americanus) was quantified for populations from New Brunswick, Quebec, Ontario, Maine, Alaska, and the island of Newfoundland. Based on a model of island biogeography developed by Case, we predicted that body size should be larger in Newfoundland bears than in mainland populations. The presence of few large predators and minimal competition between herbivore prey on Newfoundland allow an appropriate test of the model (i.e., food availability for bears may differ between populations on the mainland and in Newfoundland). In addition, sexual-selection theory predicts that the coevolution of polygyny and large size will be coupled with an increase in sexual size dimorphism. Therefore, we also predicted that among the six populations, male body mass should scale hyperallometrically with female body mass (i.e., slope > 1). Analysis of deterministic growth curves indicated that bears from Newfoundland attained greater asymptotic body size than populations on the mainland, which supports our first prediction. On average, the relative difference in asymptotic body mass between females from the island and mainland populations was 55%, while the relative difference between males was 37%. However, we found that sexual size dimorphism did not increase disproportionately with body mass among the six populations, which refuted our second prediction. We discuss a range of abiotic and biotic selection pressures possibly responsible for larger body size in Newfoundland bears. We suggest that the ability to exploit seasonally abundant and spatially dispersed dietary protein by female and male black bears on the island has been and is still a primary environmental factor selecting for large body size in Newfoundland bears. Although the relationship between sexual size dimorphism and body size is tenuous (slope [Formula: see text] 1), it does suggest that (an)other adaptive mechanism(s), opposing sexual selection for extreme male size, explain(s) a large amount of the variation in sexual size dimorphism among black bear populations.


1997 ◽  
Vol 75 (5) ◽  
pp. 731-739 ◽  
Author(s):  
Christiane Mauget ◽  
Robert Mauget ◽  
Antoine Sempéré

Indirect calorimetry measurements were made continuously over a 2-year period in 10 adult female roe deer (Capreolus capreolus) maintained in outdoor enclosures on ad libitum feeding. Results from adult nonpregnant does revealed no endogenous seasonal rhythm in resting metabolic rate (RMR), in contrast to most cervid species. Throughout the 2 years of our study, RMR (overall mean 4695 ± 65 kJ∙d−1) fluctuated in parallel with variations in body mass. The mass-specific RMR ranged from 221.2 ± 4.8 to 230.7 ± 4.0 kJ∙kg−1∙d−1 (466.0 ± 10.8 to 495.5 ± 9.7 kJ∙kg−0.75∙d−1). Results from pregnant females (five in the first year, four in the second) showed that their energy expenditure increased by 15% during the last 2 months of gestation, in step with the increase in body mass. A 27% increase in RMR was recorded in lactating females during the first month post partum. These results show that in a small-bodied cervid such as the roe deer, reproduction costs are no higher than in other wild herbivores.


Sign in / Sign up

Export Citation Format

Share Document