683 research outputs found
Why do we want to think humans are different?
One harmful consequence of creating categories where one group is unique and superior to others is that it justifies committing negative, often atrocious, acts on the members of the inferior group. Correcting divisive human categorizations (racial superiority, gender superiority) has bettered society. Scholars have often claimed that humans are unique and superior to nonhuman animals. These claims need to be reevaluated. Many have already been refuted. Animals have been shown to outperform humans in many tasks, including cognitive ones. Here we raise the question: Has the false sense of superiority been used to justify human cruelty to animals
Diversity on human difference: Unanimity on human responsibility
Further commentaries on our original target article add important new points and expand our understanding of the differences between animals, particularly between non-human and human primates. But whether they affirm or deny that humans are unique, all commentators agree that our special abilities mean we should be taking responsibility for the care of nature and the plants and animals it supports. We ask: is humankind doing this
Refining thoughts about human/nonhuman differences
Our commentators come from many fields and disciplines and express highly divergent views, illustrating broad interest in the question. From the breadth of comments, we have identified two recurring themes, which we focus on here. The first is a preponderance of cautionary remarks about evaluating the differences between humans and nonhuman animals. The second concerns whether considering animals as worthy of moral consideration is one of many useful tools for conservationists trying to prevent extinction, habitat destruction, and climate change
Trends and Variability in Localized Precipitation Around Kibale National Park, Uganda, Africa
Our objective was to understand and describe local spatial and temporal variability in precipitation around Kibale National Park, a tropical forest area of high conservation value. Continental or regional-scale trends are often relied upon to make policy and management decisions, but these analyses are often at too coarse a resolution to capture important variability at a finer scale where management actions operate. Monthly rainfall data derived from ten long-term station records (1941-1975) were used to evaluate local spatiotemporal variability in seasonal and annual rainfall for the area surrounding Kibale National Park. The magnitude, direction and significance of trends in seasonal and annual rainfall within the area surrounding the park were identified using the Mann-Kendall trend test and Sen’s slope estimator. The standardized precipitation index was calculated at 3- and 12-month periods to identify areas of relative wetness or dryness. Analysis of annual trends and precipitation indices indicated that patterns in annual time series do not reflect the direction and magnitude of seasonal trends nor the spatial variability in intra-annual rainfall at the local scale. Significant negative trends in the seasonal long rains, following dry season and short rains were identified at stations west of Kibale, while significant positive trends in the seasonal short rains occurred at stations north of the park. Stations along the western park boundary tended to have more years in which the two dry seasons were abnormally dry than those stations located further from the park
Integrating landscapes that have experienced rural depopulation and ecological homogenization into tropical conservation planning
If current trends of declining fertility rates and increasing abandonment of rural land as a result of urbanization continue, this will signal a globally significant transformation with important consequences for policy makers interested in conservation planning. This transformation is presently evident in a number of countries and projections suggest it may occur in the future in many developing countries. We use rates of population growth and urbanization to project population trends in rural areas for 25 example countries. Our projections indicate a general decline in population density that has either occurred already (e.g., Mexico) or may occur in the future if current trends continue (e.g., Uganda). Using both temperate and tropical examples we present evidence that this process will lead to ecological homogenization as a dominant habitat (e.g., forest replaces a mosaic of human-maintained landscapes), resulting in declines in biodiversity at the local scale. Building on this information, we consider research programs that need to be conducted so that policy makers are prepared to effectively manage depopulated rural areas
Parks, people and pixels: evaluating landscape effects of an East African national park on its surroundings
Landscapes surrounding protected areas, while still containing considerable biodiversity, have rapidly growing human populations and associated agricultural development in most of the developing world that tend to isolate them, potentially reducing their conservation value. Using field studies and multi-temporal Landsat imagery, we examine a forest park, Kibale National Park in western Uganda, its changes over time, and related land cover change in the surrounding landscape. We find Kibale has successfully defended its borders and prevents within-park deforestation and other land incursions, and has maintained tree cover throughout the time period of the study. Outside the park there was a significant increase in tea plantations and continued forest fragmentation and wetland loss. The question of whether the park is a conservation success because of the network of forest fragments and wetlands or in spite of them remains unanswered
Maternal Age as a Determinant of Larval Growth and Survival in a Marine Fish, \u3ci\u3eSebastes Melanops\u3c/i\u3e
Relative body size has long been recognized as a factor influencing reproductive success in fishes, but maternal age has only recently been considered. We monitored growth and starvation resistance in larvae from 20 female black rockfish (Sebastes melanops), ranging in age from five to 17 years. Larvae from the oldest females in our experiments had growth rates more than three times as fast and survived starvation more than twice as long as larvae from the youngest females. Female age was a far better predictor of larval performance than female size. The apparent underlying mechanism is a greater provisioning of larvae with energy-rich triacylglycerol (TAG) lipids as female age increases. The volume of the oil globule (composed primarily of TAG) present in larvae at parturition increases with maternal age and is correlated with subsequent growth and survival. These results suggest that progeny from older females can survive under a broader range of environmental conditions compared to progeny from younger females. Age truncation commonly induced by fisheries may, therefore, have severe consequences for long-term sustainability of fish populations
Population pressure and global markets drive a decade of forest cover change in Africa\u27s Albertine Rift
Africa\u27s Albertine Rift region faces a juxtaposition of rapid human population growth and protected areas, making it one of the world\u27s most vulnerable biodiversity hotspots. Using satellite-derived estimates of forest cover change, we examined national socioeconomic, demographic, agricultural production, and local demographic and geographic variables, to assess multilevel forces driving local forest cover loss and gain outside protected areas during the first decade of this century. Because the processes that drive forest cover loss and gain are expected to be different, and both are of interest, we constructed models of significant change in each direction. Although rates of forest cover change varied by country, national population change was the strongest driver of forest loss for all countries – with a population doubling predicted to cause 2.06% annual cover loss, while doubling tea production predicted to cause 1.90%. The rate of forest cover gain was associated positively with increased production of the local staple crop cassava, but negatively with local population density and meat production, suggesting production drivers at multiple levels affect reforestation. We found a small but significant decrease in loss rate as distance from protected areas increased, supporting studies suggesting higher rates of landscape change near protected areas. While local population density mitigated the rate of forest cover gain, loss was also correlated with lower local population density, an apparent paradox, but consistent with findings that larger scale forces outweigh local drivers of deforestation. This implicates demographic and market forces at national and international scales as critical drivers of change, calling into question the necessary scales of forest protection policy in this biodiversity hotspot. Using a satellite derived estimate of forest cover change for both loss and gain added a dynamic component to more traditionally static and unidirectional studies, significantly improving our understanding of landscape processes and drivers at work
Barking up the right tree: Understanding local attitudes towards dogs in villages surrounding Ranomafana National Park, Madagascar can benefit applied conservation
Exotic carnivores, particularly feral and domestic dogs, represent a serious threat to Madagascar’s endemic fauna. We obtained information from the local community about dogs in villages in and around Ranomafana National Park (RNP), Madagascar. Surveys were conducted (N=359) to assess local opinions of dogs, reasons for owning dogs, and the willingness of dog owners to participate in spay/neuter/vaccine programs. Of surveyed individuals without dogs (N=211), 58.9% of respondents reported negative feelings towards free-roaming dogs, with only 1% of respondents identifying free-roaming dogs as a positive aspect of village life. Of individuals with dogs (N=148), 8.1% of respondents reported using their dog for hunting, and 41.2% reported that their dog had killed at least one wild animal, with 11.8% reporting that this occurred on a weekly basis. Villagers approve of spay/neuter/vaccine programs and 90.3% of respondents with dogs state they would use them if freely available. The interest in veterinary services combined with a generally negative attitude towards free-roaming dogs indicates that a spay/neuter/vaccine program would be an effective means of controlling dog populations.RÉSUMÉLes carnivores exotiques, particulièrement les chiens domestiques et ceux retournés à l’état sauvage, représentent une menace sérieuse pour la faune endémique de Madagascar. Nous avons récolté des informations auprès des communautés riveraines sur les chiens vivant dans les villages et autour du Parc National de Ranomafana (RNP) au sud-est de Madagascar. Nous avons mené des enquêtes (N=359) afin d’évaluer les avis de la communauté locale sur les chiens, les raisons pour lesquelles les gens possèdent ces animaux et la volonté des propriétaires pour s’engager dans un programme de stérilisation/vaccination canine. Les villageois qui ne possédaient pas de chiens (N=211) représentaient 58,9 % des personnes interrogées ; ils ont rapporté avoir des sentiments négatifs envers les chiens errants et seulement 1 % des personnes interrogées ont vu un aspect positif pour la vie du village dans les chiens errants. Parmi les propriétaires de chiens (N=148), 8,1 % des personnes interrogées ont rapporté utiliser leur chien pour la chasse et 41,2% des personnes interrogées indiquent que leur chien a déjà tué au moins un animal sauvage, dont 11,8 % rapportant que cela arrivait toutes les semaines. Les villageois approuvent le programme de stérilisation/ vaccination canine et 90,3 % des propriétaires de chiens y auraient volontiers recours si celui-ci était gratuit et librement disponible
Social Structure Facilitated the Evolution of Care-giving as a Strategy for Disease Control in the Human Lineage
Humans are the only species to have evolved cooperative care-giving as a strategy for disease control. A synthesis of evidence from the fossil record, paleogenomics, human ecology, and disease transmission models, suggests that care-giving for the diseased evolved as part of the unique suite of cognitive and socio-cultural specializations that are attributed to the genus Homo. Here we demonstrate that the evolution of hominin social structure enabled the evolution of care-giving for the diseased. Using agent-based modeling, we simulate the evolution of care-giving in hominin networks derived from a basal primate social system and the three leading hypotheses of ancestral human social organization, each of which would have had to deal with the elevated disease spread associated with care-giving. We show that (1) care-giving is an evolutionarily stable strategy in kin-based cooperatively breeding groups, (2) care-giving can become established in small, low density groups, similar to communities that existed before the increases in community size and density that are associated with the advent of agriculture in the Neolithic, and (3) once established, care-giving became a successful method of disease control across social systems, even as community sizes and densities increased. We conclude that care-giving enabled hominins to suppress disease spread as social complexity, and thus socially-transmitted disease risk, increased
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