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Territorial behaviour can only be adaptive if its costs are outweighed by its benefits. Territorial individuals incur costs by defending their territories against intruders. Usually these intruders are assumed to be non-territorial floaters attempting to take over the whole territory or neighbours trying to extend the borders of their own territory. We instead investigate how costs and benefits of territorial behaviour are affected by neighbours which invade to steal resources on a territory.We show analytically that in the absence of defence intrusion into neighbouring territories always pays and that even if territories are defended intrusion levels can still be high. Using a more detailed simulation model we find that territory defence usually disappears from the population even if owners have a strong advantage over intruders in terms of fighting costs or foraging efficiency. Defence and thus territoriality can only be evolutionarily stable if fighting costs for the intruder relative to the productivity of the territory are very high or if crossing the borders between territories carries additional costs.Our results show that stealing of resources by neighbours can have a considerable effect on the evolutionary stability of territory defence and thus territoriality itself. A more mechanistic model of territorial behaviour is needed to incorporate these kinds of mechanisms into a general theory on the evolution of territoriality. 相似文献
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Managing Human Tissue Transfer Across National Boundaries – An Approach from an Institution in South Africa
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With biobank research on the increase and the history of exploitation in Africa, it has become necessary to manage the transfer of human tissues across national boundaries. There are many accepted templates of Material Transfer Agreements (MTAs) that currently exist internationally. However, these templates do not address the specific concerns of South Africa and even of Africa as a continent. This article will examine three significantly important ethico‐legal concepts that were deliberated and carefully adapted by a South African Institution to suit the transfer of Human Biological Materials (HBMs) and associated data for biobank research, namely: informed consent; benefit sharing arrangements; and ownership together with intellectual property rights in human tissues. The discussion includes an analysis of current practice; the ethico‐legal challenges in the South African/African context; the decisions made with regard to how the related ethico‐legal challenges were addressed in the MTA; and justifications for implementing these decisions. The processes considered could be of benefit to other developing world countries who consider it necessary to manage the transfer of HBMs across national boundaries. 相似文献
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Shiro Horiuchi 《Ecological Research》2008,23(3):551-556
Previous studies have discussed the evolution of ownership using the Hawk–Dove–Bourgeois game. Decisive parameters are resource
values (V) and contest costs (C). However, ownership may also evolve as a result of the effects of population density. To compare the effects of population
density with those of resource values, I created a learning-based model of a revised Hawk–Dove–Bourgeois game. The game simulates
the dynamics of agents that struggle for regions (“territories”) along a line. With appropriate sets of r (resource value) and l (reciprocal of the population density), the model showed that ownership is more likely to evolve when the resource value
is small and population density is high. An area containing high-value resources is likely to accompany high population density.
However, simulations showed that population density has stronger effects than resource value on the evolution of ownership. 相似文献
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Evaristo Barrera-Algarín Francisco Estepa-Maestre José Luís Sarasola-Sánchez-Serrano José Carlos Malagón-Siria 《Revista espa?ola de geriatría y gerontología》2021,56(4):208-217
PurposeTo find out whether elements such as public expenditure, the coverage ratio, public or private ownership, and the size of Nursing homes relate to the number of deaths in residences per COVID-19.Material and methodsA total of 15 variables are analyzed in 17 Autonomous Communities (n = 17), where the following stand out: public expenditure per dependent person; incidence of COVID-19 in each Autonomous Community; deaths in Nursing homes by COVID-19; and analysis of places in Nursing homes. Reliability of r = 0.613. Regression analyses are carried out with the different variables, and ANOVA tests.ResultsPercentages of deaths by COVID-19 in Nursing homes, between 40% and 88%, of the total of (p < 0.001, X2 = 0.975). A relationship is established between the number of deaths from COVID-19 in Nursing homes, and the higher number of private Nursing homes (p < 0.001, X2 = 0.633). The larger the size of the Nursing home, the more deaths by COVID-19 were recorded (p < 0.001, X2 = 0.787), with private Nursing homes having +100 places, and public Nursing homes having +100 places (p < 0.001, X2 = 0.808).ConclusionsIt was found that there is a relationship between the number of deaths from COVID-19 in Nursing homes, and the fact that there are a greater number of private Nursing homes in that autonomous community. It was detected that the model of Nursing home best prepared to face the COVID-19: public Nursing homes with less than 25 places. 相似文献
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Many animal species have morphological and cognitive adaptations for fighting with others to gain resources, but it remains unclear how humans make fighting decisions. Non-human animals adaptively calibrate fighting behavior to ecological variables such as resource quantity and resource distribution. Also, many species reduce fighting costs by resolving disputes based on power asymmetries or conventions. Here we show that humans apply an ownership convention in response to the problem of costly fighting. We designed a virtual environment where participants, acting as avatars, could forage and fight for electronic food items (convertible to cash). In two experimental conditions, resources were distributed uniformly or clustered in patches. In the patchy condition, we observed an ownership convention — the avatar who arrives first is more likely to win — but in the uniform condition, where costly fights are rare, the ownership convention is absent. 相似文献
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Loane Skene 《Journal of bioethical inquiry》2007,4(2):129-133
This paper outlines the current common law principles that protect people’s interests in their bodies, excised body parts
and tissue without conferring the rights of full legal ownership. It does not include the recent statutory amendments in jurisdictions
such as New South Wales and the United Kingdom. It argues that at common law, people do not own their own bodies or excised
bodily material. People can authorise the removal of their bodily material and its use, either during life or after their
death, for medical or scientific purposes. Researchers who acquire human bodies, body parts or tissue pursuant to such an
authority have a right to possess and use them according to the authorisation they have been given, but their rights fall
short of full ownership because they are limited in the way that they can use the material. The legal rights of researchers
who develop intellectual property and biological products from excised human tissue can be adequately protected by existing
common law principles without the need for a new legal principle that people own body parts and tissue removed from their
bodies.
相似文献
Loane SkeneEmail: |
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