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Several Predictions (several + prediction)
Selected AbstractsZoo and aquarium animal management and conservation: current trends and future challengesINTERNATIONAL ZOO YEARBOOK, Issue 1 2003M. HUTCHINS The turn of the century appears to be a good time to examine the role of zoos and aquariums, both in the past and present, and to predict what role these organizations will play in animal management and conservation in the future. In this review three main trends are considered: (1) the loss of wildlife habitats and, therefore, wildlife, (2) the increase in the number of animal-welfare and animal-rights organizations, and (3) the continued urbanization of the Earth's human population. Several predictions and positive action points are given for each trend and if these are taken on board and developed, zoos and aquariums of the future may become leaders in conservation, education and science. [source] Natal Attraction in Adult Female Baboons (Papio cynocephalus ursinus) in the Moremi Reserve, BotswanaETHOLOGY, Issue 8 2003Joan B. Silk Mammalian females are strongly attracted to infants and interact regularly with them. Female baboons make persistent attempts to touch, nuzzle, smell and inspect other females' infants, but do not hold them for long periods, carry them, or provide other kinds of care for them. Mothers generally tolerate these interactions, but never initiate them. The function of these brief alloparental interactions is not well understood. Infant handling might be a form of reproductive competition if females' interest in infants causes distress to mothers or harm to their infants. Alternatively, infant handling might be the product of selection for appropriate maternal care if females who are highly responsive to infants are the most successful mothers. We test several predictions derived from these hypotheses with data collected in a free-ranging group of baboons (Papio cynocephalus ursinus) in the Moremi Reserve of Botswana. Infants were most attractive when they were very young. Mothers of young infants were approached by other adult females on average once every 6 min, and other females attempted to handle their infants approximately once every 9 min. By the time infants were a year old, their mothers were being approached only once every 30 min and infants were being handled only once every 5 h. Females were more strongly attracted to other females' infants when they had young infants of their own, and their interest in other females' infants declined as their own infants matured. Females seemed to be equally attracted to all infants, but had greater access to offspring of their relatives and subordinate females. Females nearly always grunted as they handled infants. As in other contexts grunts are a reliable predictive signal that non-aggressive behavior will follow, the use of grunts before handling suggests that these interactions were not a form of deliberate harassment. [source] THE COMBINED EFFECTS OF RIVERS AND REFUGIA GENERATE EXTREME CRYPTIC FRAGMENTATION WITHIN THE COMMON GROUND SKINK (SCINCELLA LATERALIS)EVOLUTION, Issue 2 2010Nathan D. Jackson Rivers can act as both islands of mesic refugia for terrestrial organisms during times of aridification and barriers to gene flow, though evidence for long-term isolation by rivers is mixed. Understanding the extent to which riverine barrier effects can be heightened for populations trapped in mesic refugia can help explain maintenance and generation of diversity in the face of Pleistocene climate change. Herein, we implement phylogenetic and population genetic approaches to investigate the phylogeographic structure and history of the ground skink, Scincella lateralis, using mtDNA and eight nuclear loci. We then test several predictions of a river,refugia model of diversification. We recover 14 well-resolved mtDNA lineages distributed east,west along the Gulf Coast with a subset of lineages extending northward. In contrast, ncDNA exhibits limited phylogenetic structure or congruence among loci. However, multilocus population structure is broadly congruent with mtDNA patterns and suggests that deep coalescence rather than differential gene flow is responsible for mtDNA,ncDNA discordance. The observed patterns suggest that most lineages originated from population vicariance due to riverine barriers strengthened during the Plio,Pleistocene by a climate-induced coastal distribution. Diversification due to rivers is likely a special case, contingent upon other environmental or biological factors that reinforce riverine barrier effects. [source] TESTS OF SEX ALLOCATION THEORY IN SIMULTANEOUSLY HERMAPHRODITIC ANIMALSEVOLUTION, Issue 6 2009Lukas Schärer Sex allocation is a crucial life-history parameter in all sexual organisms. Over the last decades a body of evolutionary theory, sex allocation theory, was developed, which has yielded capital insight into the evolution of optimal sex allocation patterns and adaptive evolution in general. Most empirical work, however, has focused on species with separate sexes. Here I review sex allocation theory for simultaneous hermaphrodites and summarize over 50 empirical studies, which have aimed at evaluating this theory in a diversity of simultaneous hermaphrodites spanning nine animal phyla. These studies have yielded considerable qualitative support for several predictions of sex allocation theory, such as a female-biased sex allocation when the number of mates is limited, and a shift toward a more male-biased sex allocation with increasing numbers of mates. In contrast, many fundamental assumptions, such as the trade-off between male and female allocation, and numerous predictions, such as brooding limiting the returns from female allocation, are still poorly supported. Measuring sex allocation in simultaneously hermaphroditic animals remains experimentally demanding, which renders evaluation of more quantitative predictions a challenging task. I identify the main questions that need to be addressed and point to promising avenues for future research. [source] Iridescent hindwing patches in the Pipevine Swallowtail: differences in dorsal and ventral surfaces relate to signal function and contextFUNCTIONAL ECOLOGY, Issue 4 2010Ronald L. Rutowski Summary 1.,Iridescent colour signals are directional but, like diffusely reflected colours, vary within and among species in ways that may be adaptations to specific types of receivers in specific light environments. 2.,The hindwings of pipevine swallowtail butterflies exhibit brilliant blue and iridescent colour patches on the ventral surface in both sexes and on the dorsal wing surface in males. Evidence suggests that the ventral iridescent blue is a component of the warning coloration of this distasteful species, while the dorsal blue iridescent wing area is a sexual signal. Given differences in the function and ecological context of signal production, we analysed reflectance spectra from the iridescent blue areas of both field-caught and laboratory-reared animals to test several predictions about the iridescent colour patches on these wing surfaces. 3.,The ventral blue patches in the warning coloration of males and females should be most visible early and late in the day, due to wing orientation relative to sun angle. We therefore predicted that these iridescent colour patches would be brighter and of longer wavelengths than the male dorsal blue patch displayed during midday courtships. The prediction about reflectance intensity was supported but the prediction about hue was not. 4.,We predicted that the sexually selected dorsal hindwing iridescence of males would be more variable among individuals and condition dependent than the naturally selected ventral iridescent colour patches. To assess variation and condition dependence, laboratory-reared and field-captured individuals were compared. The prediction about variation was not supported, but only the dorsal wing surfaces showed evidence of being condition dependent. 5.,We investigated whether development of dorsal and ventral blue iridescence was coupled by determining correlations in colour properties between the wing surfaces. Our finding of positive correlations indicated a potential developmental constraint in the evolution of colour differences between the two wing surfaces. 6.,Results of this study suggest that some properties of iridescent coloration on the hindwing of the pipevine swallowtail (especially intensity) may have been fine-tuned by evolution in response to prevailing ambient light conditions and viewing perspectives that differ among types of signal receivers. [source] Poleward shifts in breeding bird distributions in New York StateGLOBAL CHANGE BIOLOGY, Issue 8 2009BENJAMIN ZUCKERBERG Abstract Like other regions of the northern hemisphere, the northeastern United States has experienced a general increase in regional temperatures over the past 20 years. Quantifying the ecological implications of these changing temperatures has been severely constrained by a lack of multispecies distributional data by which to compare long-term changes. We used the New York State Breeding Bird Atlas, a statewide survey of 5332 25 km2 blocks surveyed in 1980,1985 and 2000,2005, to test several predictions that the birds of New York State are responding to climate change. Our objective was to use an information-theoretic approach to analyze changes in three geographic range characteristics, the center of occurrence, range boundaries, and states of occurrence to address several predictions that the birds of New York State are moving polewards and up in elevation. As expected, we found all bird species (n=129) included in this analysis showed an average northward range shift in their mean latitude of 3.58 km [Prob(Ha|data)=0.87)]. Past studies have found that northern range boundaries are more likely to be influenced by climatic factors than southern range boundaries. Consequently, we predicted that northward shifts would be more evident in northern as opposed to southern range boundaries. We found, however, that the southern range boundaries of northerly birds moved northward by 11.4 km [n=43, Prob(Ha|data)=0.92], but this pattern was less evident in northern range boundaries of southerly birds. In addition, we found that bird species demonstrated a general shift downhill in their mean elevation, but demonstrated little change in their elevational boundaries. The repeated pattern of a predicted northward shift in bird ranges in various geographic regions of the world provides compelling evidence that climate change is driving range shifts. [source] Interaction of landscape and life history attributes on genetic diversity, neutral divergence and gene flow in a pristine community of salmonidsMOLECULAR ECOLOGY, Issue 23 2009DANIEL GOMEZ-UCHIDA Abstract Landscape genetics holds promise for the forecasting of spatial patterns of genetic diversity based on key environmental features. Yet, the degree to which inferences based on single species can be extended to whole communities is not fully understood. We used a pristine and spatially structured community of three landlocked salmonids (Salvelinus fontinalis, Salmo salar, and Salvelinus alpinus) from Gros Morne National Park (Newfoundland, Canada) to test several predictions on the interacting effects of landscape and life history variation on genetic diversity, neutral divergence, and gene flow (m, migration rate). Landscape factors consistently influenced multispecies genetic patterns: (i) waterfalls created strong dichotomies in genetic diversity and divergence between populations above and below them in all three salmonids; (ii) contemporary m decreased with waterway distance in all three species, while neutral genetic divergence (,) increased with waterway distance, albeit in only two taxa; (iii) river flow generally produced downstream-biased m between populations when waterfalls separated these, but not otherwise. In contrast, we expected differential life history to result in a hierarchy of neutral divergence (S. salar > S. fontinalis > S. alpinus) based on disparities in dispersal abilities and population size from previous mark-recapture studies. Such hierarchy additionally matched varying degrees of spatial genetic structure among species revealed through individual-based analyses. We conclude that, whereas key landscape attributes hold power to predict multispecies genetic patterns in equivalent communities, they are likely to interact with species-specific life history attributes such as dispersal, demography, and ecology, which will in turn affect holistic conservation strategies. [source] | ||||||||||