COLLABORATIVE RESEARCH: Testing predictions of the core-satellite and resource-breadth hypotheses in small mammal communities: field tests of a macroecological pattern

你有没有想过为什么有些动物(如松鼠、浣熊和乌鸦)很常见，似乎随处可见，而另一些动物则很稀有，只出现在少数几个地方？生态学家也提出了这个问题，他们已经为这个谜题研究了一个多世纪。答案可能取决于动物可以吃的食物的种类，动物长距离移动的能力，或者两者兼而有之。一方面，可以靠一系列不同的食物茁壮成长的动物，也就是生态学家有时称之为多面手的动物，应该是普遍和普遍的，而挑食的动物应该是罕见的，只在少数地方才能找到。另一方面，能够迅速进入它们消失的地区的动物也应该是常见和普遍的，而留在原地的动物应该是稀有的，只在少数地方发现。就像生态学中的许多答案一样，这可能两者兼而有之。该项目的研究人员正在努力发现饮食和运动能力如何决定动物生活的地点，以及特定地区有多少人生活。这一研究项目的结果可能有助于理解为什么一些物种(如濒危物种)在受到法律保护后稀有且恢复缓慢，而其他物种(如本地害虫或入侵物种)即使在人类发展的情况下也很常见。通过这个项目，研究人员将培训两名研究生、一名项目经理和四名研究助理，并将利用现有的长期实验基础设施，将本科实地课程集中在各自的机构。物种丰富度与其活动范围大小之间的正相关关系是生态学中最普遍的模式之一。汉斯基的核心-卫星假说和布朗的资源-广度假说是解释这一模式的两个特别引人注目的假说。核心-卫星假说假定，不同的运动速度是丰度-分布关系的基础，因此，广泛分布的物种通过从周围地区扩散来缓冲当地的灭绝。相比之下，资源呼吸假说提出了物种利用一系列资源的能力的差异：丰富、分布广泛的物种应该是能够开发更广泛种类资源的生态通才，而不是稀有的、受地理限制的物种(即生态专家)。然而，尽管它们的直觉吸引力很大，但对每个假说的核心、相反的预测的支持一直很少，即一个地点的新个体应该主要来自分散(核心-卫星假说)和原位繁殖(资源-广度假说)。研究人员将把消费者-资源互动与估计在食草性小型哺乳动物(啮齿动物、地鼠、象地鼠)中的扩散和就地招募结合起来。在一项预先存在的长期实验中，将建立两种操作，即建立扩散障碍和移除资源。根据这一奖项，研究人员将确定是否通过更高的扩散速度、就地招募或两者兼而有之，来维持丰富、广泛的物种的广泛分布。这一奖项反映了NSF的法定使命，并通过使用基金会的智力优势和更广泛的影响审查标准进行评估，被认为值得支持。

Have you ever wondered why some animals (like squirrels, raccoons, and crows) are common and seem to be found everywhere, while others are rare and occur only in a few places? Ecologists have asked this question too, and they have been working on this puzzle for over a century. The answer could depend on the variety of foods that animals can eat, the ability of animals to move long distances, or both. On the one hand, animals that can thrive on a range of different foods, what ecologists sometimes call generalists, should be common and widespread, while picky eaters should be rare and found only in a few places. On the other hand, animals that can quickly move into areas from which they have disappeared should also be common and widespread, while animals that stay put should be rare and found in only a few places. Like many answers in ecology, it's probably some of both. The researchers on this project are working to discover how diet and movement ability shape where animals live and how many individuals live in a particular area. Results of this research project could be useful in understanding why some species (like endangered species) are rare and slow to recover following legal protections, while other species (like native pests or invasive species) are common, even in the face of human development. Through this project, the researchers will train two graduate students, a project manager, and four research assistants, and will use the existing infrastructure of a long-term experiment around which to center undergraduate field courses at their respective institutions. Positive correlations between a species' abundance and its range size are among the most general patterns in ecology. Two particularly compelling hypotheses, Hanski's Core-Satellite hypothesis and Brown's Resource-Breadth hypothesis, have been proposed to explain this pattern. The Core-Satellite hypothesis posits that differential rates of movement underlie abundance-distribution relationships, such that widespread species are buffered against local extinction by dispersal from the surrounding region. In contrast, the Resource-Breath hypothesis invokes differences in the ability of species to exploit a range of resources: abundant, widespread species should be ecological generalists capable of exploiting a wider variety of resources than rare, geographically restricted species (i.e., ecological specialists). For all of their intuitive appeal, however, support for the central, contrasting predictions of each hypothesis, that new individuals at a locality should arise mostly from dispersal (Core-Satellite hypothesis) versus in situ reproduction (Resource-Breadth hypothesis), has been scant. The researchers will integrate consumer-resource interactions with estimates of dispersal and in situ recruitment in a guild of herbivorous small mammals (rodents, shrews, elephant shrews). Two manipulations, the erection of dispersal barriers and a resource removal, will be established within a pre-existing, long-term experiment. Under this award, the researchers will determine whether abundant, widespread species maintain their extensive distributions through higher rates of dispersal, in situ recruitment, or both.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.