Mechanisms and Functions of Sexual Segregation in Habitat Use

栖息地使用中性别隔离的机制和功能

基本信息

批准号：
NE/E001181/1
负责人：
Darren Croft
金额：
$ 8.69万
依托单位：
Bangor University
依托单位国家：
英国
项目类别：
Research Grant
财政年份：
2007
资助国家：
英国
起止时间：
2007 至无数据
项目状态：
已结题

来源：
https://gtr.ukri.org/projects?ref=NE%2FE001181%2F1
关键词：
Mechanisms Functions Sexual Segregation Habitat

项目摘要

In many animals males and females may live apart for some or most of their lives termed sexual segregation. Sex segregation may occur when the sexes use different parts of their environment. Ancient Greek mythology tells of a nation of female warriors known as the Amazons who lived on an island. The Amazons only met with men to trade and reproduce and kept all daughters on the island. Whilst the degree of truth in this ancient myth is open to debate, in animals sex differences in habitat use are common and understanding why and how this behaviour occurs is essential if we are going to conserve and protect species and habitats. For example, if sex segregation occurs it may be necessary to protect different habitats for males and females. However, we have to understand why and how this behaviour occurs to be able to do this. For some time scientists have tried to understand why the sexes segregate in habitat use. In the 1900's Charles Darwin pondered over why red deer live apart for much of the year. In recent years many explanations have been proposed, of which three are probably important. The first idea hinges on the fact that in many species males and females are attacked at different rates by predators. Males may be larger and be equipped with weapons such as the antlers, which may allow them to use habitats with increased predation risk. The second idea suggests that males and females may differ in their nutritional requirements, for example due to pregnancy, which may lead to the sexes selecting different habitats to meet these nutritional needs. Finally, harassment of females by males is common in the animal kingdom and frequently causes injury to females or their offspring. The final idea suggests that females occupy habitats with no males to reduce this harassment. Previous work on sex segregation has generally focused on hoofed animals such as deer and sheep, but because of their large size and the amount of space they need to roam, scientists have generally been able to do little more than describe patterns of segregation. In contrast the proposed study will experimentally test these hypotheses using a small species of freshwater fish 'guppies' on the island of Trinidad in the Carribean as a model system. Guppies form relatively small populations in different streams that vary in the number of predators they face. Furthermore, guppies can easily be kept in the laboratory, making them particularly suitable for this investigation. We know that guppies living under high predation risk segregate by sex, with male guppies (which are more vulnerable to predation) occupying areas of shallow water, which are thought to be safer from predators, suggesting that predation risk is important in driving sexual segregation. However, the benefits that they gain from segregation remain unknown. For example, why do females accept a greater risk of predation? Is it to reduce sexual harassment or because there is less competition for food? Or is it a combination of the two? We also do not know how patterns of sex segregation arise, or why some males and females live in the same parts of the river. Does it dependent on environmental conditions? How is it affected by differences in the number of males and females and the density of the population? I will compare the degree of sex segregation between 10 populations of wild guppies living under different risks of predation in the rivers of Trinidad. In each river I will assess the levels of sex segregation and compare it to the risk of predation, population structure and habitat type (e.g. water depth) testing predictions from the main ideas thought to drive sex segregation. In addition to observing patterns of behaviour in the wild this study will observe the behaviour of guppies in the laboratory where it is possible to measure the level of sex segregation in a standard environment and test the factors thought to drive sex segregation in isolation.

在许多动物中，男性和女性可能会在某些或大部分的生活中分开生活。当性别使用环境的不同部分时，可能会发生性隔离。古希腊神话讲述了一个被称为亚马逊居住在岛上的女战士的国家。亚马逊只会与男人会面进行贸易和繁殖，并将所有女儿留在岛上。尽管这个古老的神话中的真理程度是持争取辩论的，但在栖息地的性别差异中很普遍，并且了解这种行为的发生是为什么，如果我们要保护和保护物种和栖息地，那么这种行为是必不可少的。例如，如果发生性隔离，则可能有必要保护男性和女性的不同栖息地。但是，我们必须了解这种行为的原因以及如何能够做到这一点。一段时间以来，科学家一直试图理解为什么性别在栖息地使用中分离。在1900年代，查尔斯·达尔文（Charles Darwin）思考了为什么红鹿在一年中大部分时间分开生活。近年来，已经提出了许多解释，其中三个可能很重要。第一个想法取决于以下事实：在许多物种中，雄性和女性受到掠食者的攻击。雄性可能更大，并配备了鹿角等武器，这可能使他们可以使用具有增加捕食风险的栖息地。第二个想法表明，男性和女性的营养需求可能有所不同，例如由于怀孕而导致的，这可能会导致性别选择不同栖息地以满足这些营养需求。最后，男性在动物界很常见骚扰女性，经常会对女性或其后代造成伤害。最后的想法表明，女性占据没有男性的栖息地来减少这种骚扰。以前关于性别隔离的工作通常集中在鹿和绵羊等蹄动物上，但是由于它们的大小和漫游所需的空间数量，科学家通常只能做一些不仅仅是描述隔离的模式。相比之下，拟议的研究将通过在加勒比海岛上的特立尼达岛上用作模型系统的淡水鱼“孔雀鱼”，在实验中检验这些假设。孔雀鱼在其面临的捕食者数量中变化的不同流中相对较小的种群。此外，孔雀鱼可以很容易地保存在实验室中，使其特别适合此调查。我们知道，生活在高捕食风险下的孔雀鱼会被性别隔离，男性孔雀鱼（更容易受到捕食）占据了浅水区域，被认为从掠食者中更安全，这表明捕食风险对于驱动性隔离很重要。但是，它们从种族隔离中获得的好处仍然未知。例如，为什么女性接受更大的捕食风险？是为了减少性骚扰还是因为食物的竞争较少？还是两者的组合？我们也不知道性别隔离的模式是如何出现的，或者为什么有些男性和女性生活在河的同一地区。它取决于环境条件吗？它如何受到男性和女性数量以及人口密度的差异的影响？我将比较在特立尼达河流中捕食不同风险的10种野孔孔之间的性别隔离程度。在每条河中，我将评估性别隔离的水平，并将其与捕食，种群结构和栖息地类型（例如水深度）的风险进行比较，从被认为驱动性隔离的主要思想中测试预测。除了观察野外行为模式外，这项研究还将观察到实验室中的孔雀鱼的行为，在这些研究中，可以在标准环境中衡量性别隔离水平，并测试被认为隔离性别隔离的因素。