Evaluating the Influence of Scale on Paleoecological Results

一个多世纪以来，古生物学家和生物学家一直在努力解决“为什么这个地方会有这么多物种？”这个问题，但没有达成共识。面对全球性的环境危机，这个问题变得至关重要；我们必须了解生物多样性、生态系统稳定性和灭绝的驱动因素。每一项关于化石和生物多样性的研究都在特定的空间、时间或数值尺度上收集适合于每一项研究的数据，但对多项研究的荟萃分析，每项研究收集的数据都在不同的尺度上，往好里说是有问题的，往坏里说是非常不准确的。科学家们迫切需要解决规模问题，这样我们才能准确地理解生物多样性及其对保护的影响。我的研究将调查抽样中尺度对分析和结果的影响。具体来说，我的问题是：1)结果会随着规模的扩大而改变吗？例如，如果一个环境参数影响了在一个小样本中收集到的物种数量，那么增加样本量会识别出相同的环境因素，还是分析会指向一个完全不同的参数？2)如果结果随着尺度的增加而变化，这种变化是真实的，是来自不同尺度下实际的生态/进化驱动因素，还是来自分析不同尺度样本产生的数学人工产物？对当今物种的研究对于理解当今的生物多样性至关重要，但这些项目是在已经受到人类影响的生态系统上进行的。保护古生物学研究化石系统，以更好地理解和帮助恢复或保护现代生物多样性，这门学科在恢复人类影响前、基线条件和物种如何应对环境危机的信息方面显示出了希望。因此，我和我的实验室将研究规模如何影响生物多样性研究的结果，不仅使用现代海洋无脊椎动物物种，还使用古代海洋贝类动物的化石。这项研究由两个以化石保存异常而闻名的时区的平行研究组成。我的实验室将把佛罗里达现在的软体动物壳样本与过去500万年（上新世-更新世）在同一地区的软体动物壳化石进行比较。2)为了研究结果是否可以在更大的时间尺度上推广，我的实验室还将收集加拿大西部大约3.7至3.9亿年前（泥盆纪）的腕足类动物壳。本研究将对生物多样性和保护古生物学的研究产生重大影响，但具有更广泛的意义。任何需要抽样的学科或研究，以及那些受空间、时间、数量或任何其他可量化参数影响的样本，都会受到规模所带来的同样类型的问题的影响，并将受益于我的研究结果。

Paleontologists and biologists have struggled with the question "why are there this many species in this place?" for over a century without achieving a consensus. In the face of a global environmental crisis, this question has become critical; we must understand the drivers of biodiversity, ecosystem stability, and extinction. Each study of fossil and biological biodiversity collects data at specific spatial, time, or numerical scales appropriate to each study, but meta-analysis of multiple studies, each with data collected at different scales have proved to be problematic at best and grossly inaccurate at worst. Scientists urgently need to address the issue of scale so that we can accurately understand biodiversity and its implications in addressing conservation. My research will investigate the effects of scale in sampling on analyses and results. Specifically, I am asking: 1) do results change from smaller to larger scales? For example, if an environmental parameter influences the number of species collected in a small sample, would an increase in sample size identify the same environmental factor, or would the analysis point to an entirely different parameter? 2) If results change with an increase in scale, is the change real, coming from an actual ecological/evolutionary driver working at different scales, or to a mathematical artifact that arose from analyzing samples of different scales? Research on present-day species are critical to understanding present-day biodiversity, but these projects are undertaken on ecosystems already impacted by humans. The discipline of conservation paleobiology, which looks at fossil systems to better understand and help restore or preserve modern biodiversity, has shown promise in recovering pre-human-impact, baseline conditions and information of how species respond to environmental crises. Therefore, my lab and I will investigate how scale influences the outcomes of biodiversity research using not only modern marine invertebrate species, but also the fossils of ancient marine shelled animals. The research consists of parallel studies from two time-regions known for exceptional fossil preservation. 1) My lab will compare present-day samples of mollusc shells of Florida to fossil mollusc shells from the past 5 million years (Plio-Pleistocene) in the same area. 2) To investigate if results are generalizable across larger temporal scales, my lab will also collect brachiopod shells from approximately 370 to 390 million years ago (Devonian) of western Canada. The impacts of this research will be substantial for studies in biodiversity and conservation paleobiology, but have broader implications. Any discipline or study that requires sampling, and those samples are affected by space, time, number, or any other quantifiable parameter, are subject to the same sorts of problems imposed by scale and will benefit from the results of my research.