theory predicts that the plastic expression of sex-traits should be modulated not only by their production costs but also by the benefits derived from the presence of rivals and mates, yet there is a paucity of evidence for an adaptive response of sex-trait expression to social environment. We studied antler size, a costly and plastic sex trait, and tooth wear, a trait related to food intake and longevity, in over 4,000 male Iberian red deer (Cervus elaphus hispanicus) from 56 wild populations characterized by two contrasting management practices that affect male age structure and adult sex-ratio. As a consequence, these populations exhibit high and low levels of male-male competition for mating opportunities. We hypothesized that males under conditions of low intra-sexual competition would develop smaller antlers, after controlling for body size and age, than males under conditions of high intra-sexual competition, thus reducing energy demands (i.e. reducing intake and food comminution), and as a consequence, leading to less tooth wear and a concomitant longer potential lifespan. our results supported these predictions. to reject possible uncontrolled factors that may have occurred in the wild populations, we carried out an experimental design on red deer in captivity, placing males in separate plots with females or with rival males during the period of antler growth. Males living with rivals grew larger antlers than males living in a female environment, which corroborates the results found in the wild populations. As far as we know, these results show, for the first time, the modulation of a sexual trait and its costs on longevity conditional upon the level of intra-sexual competition. The expression of many sex-traits is plastic and responds to individual-and population-specific reaction norms 1-6. There is evidence for many species that environmental factors (e.g. resource availability) affect body condition and the expression of sex-traits, such as signals and weapons 1,7-11. Condition-dependence theory relies on the relative value of energy costs, because costs of producing traits are expected to be lower for individuals in good condition as compared to those in poor condition 12-15. But also, in a sexual selection context, rivals and potential mates in the social environment strongly influence the benefits associated with trait expression, so that trait investment should respond in a trade-off fashion depending on the costs but also on the benefits of trait development. One example of this in the inter-sexual selection context is that male zebra finches invest more in coloring their beaks when there are females to receive the signal 16. For intra-sexual competition, the challenge hypothesis 2 applied this idea to testosterone production relative to the probability of winning contests, which may be related

In the last decades, climate change has caused an increase in mean temperatures and a reduction in average rainfall in southern Europe, which is expected to reduce resource availability for herbivores. Resource availability can influence animals' physical condition and population growth. However, much less is known on its effects on reproductive performance and sexual selection. In this study, we assessed the impact of three environmental factors related to climate change (rainfall, temperature and vegetation index) on Iberian red deer Cervus elaphus hispanicus reproductive timing and sexual behaviour, and their effects on the opportunity for sexual selection in the population. We measured rutting phenology as rut peak date, the intensity of male rutting activity as roaring rate, and the opportunity for sexual selection from the distribution of females among harem holding males in Doñana Biological Reserve (Southwest Spain), from data of daily observations collected during the rut over a period of 25 years. For this study period, we found a trend for less raining and hence poorer environmental conditions, which associated with delayed rutting season and decreased rutting intensity, but that appeared to favour a higher degree of polygyny and opportunity for sexual selection, all these relationships being modulated by population density and sex ratio. This study highlights how climate change (mainly rainfall reduction in this area) can alter the conditions for mating and the opportunity for sexual selection in a large terrestrial mammal.

Mammals are the third most threatened group of vertebrates and tropical ones are the most endangered according to recent studies. The Buenaventura Reserve protects 20 km 2 of Montane Tropical forest in the southwestern part of the Ecuadorian Andes. This study estimates the mammal species richness of this reserve by using camera traps and occasional sightings. We recorded 20 species of large and medium-sized mammals in this small protected area, which shows the reserve's important role in the conservation of these species. This study also shows the conservation priority that these forests should have in the western part of the Ecuadorian Andes.

Body condition for reproduction in capital breeders such as the red deer (Cervus elaphus) is mostly determined by their stored energy reserves. Thus, environmental conditions and resource availability may affect reproductive performance and breeding success. In warm Mediterranean regions, current climate change is driving to a hotter and drier scenario that is expected to affect the biology and dynamics of many populations. We examined the impact of these local climate variations on red deer body condition and the relationship with female reproductive phenology and breeding success. We used satellite information of landscape vegetation along with a 22-year data series of direct field behavioural observations during the rutting season in Doñana National Park (SW Spain). We analyzed faecal nitrogen content (FN) from faeces collected during the rut. We found that poor vegetation availability in drier years was related to worse body condition of deer (measured by FN) and a delay in the rutting season, which associated with lower reproductive rates (measured by the proportion of females with calves observed the next year). We also evidenced an interesting interaction between environmental conditions in consecutive years on the timing of breeding season, with timing of breeding being more delayed when previous year resource availability was high and many females bred, and the consecutive one was poor, so females hardly recovered condition and the rut occurred later. These findings highlight the carry-over effect of reproduction in capital breeders and the potential impact of climate-change conditions on red deer breeding.

An adult female Kinosternon leucostomum was found in Buenaventura Forest Reserve, El Oro province, Ecuador, on 1 August 2014 at an altitude of 523 m above sea level. This is the first report for this species in the province and is about 130 km south of the previously southernmost known location.