Natural and Null Food Webs: A Critical Investigation of Biological and Methodological Explanations for Food Web Structure

[905446]马丁内斯食物网理论正经历着从食物网的尺度不变模式到恒定连接和尺度依赖模式的范式转变。这项博士后启动资助将通过严格和系统地比较经验观察到的食物网模式与无效和机械模型产生的模式，来澄清目前尚未确定的转变的生物学意义。正如丰富的生态学历史所表明的那样，这种比较对于评估稳健的食物网模式表明强大的生物过程限制了生态系统的结构和功能的说法至关重要。缺乏比较，食物网模式是方法学上的人工产物的假设需要在对模式的生物学基础进行大量工作之前进行系统研究。以前比较自然食物网和非食物网的工作相对较少，这表明生物过程是造成广泛的陆地、水生和海洋生态系统中相对较低的连通性的原因。为了描述这种和其他食物网模式的过程，候选的生物机制将被形式化到构建食物网的计算机模型中。以这种方式构建的网将与经验观察到的食物网进行比较。这种比较将表明模拟机制是否值得进一步的分析和实验研究，作为食物网模式的潜在来源。

9905446MartinezFood-web theory is undergoing a paradigmatic shift from scale-invariant patterns in food webs to constant connectance and scale-dependent patterns. This postdoctoral starter grant will clarify the currently undetermined biological significance of the shift by rigorously and systematically comparing empirically observed food web patterns with patterns generated by null and mechanistic models. As a rich history in ecology has shown, such comparisons are critical to evaluating the claim that robust food web patterns are indicative of powerful biological processes that constrain the structure and function of ecological systems. Lacking the comparisons, the hypothesis that food web patterns are methodological artifacts needs to be systematically studied before much work on the biological basis for the patterns is warranted. The relatively small amount of previous work comparing natural and null food webs suggests that biological processes are responsible for the relatively low value of connectance in a wide range of terrestrial, aquatic and marine ecological systems. In an attempt to delineate the processes responsible for this and other food web patterns, candidate biological mechanisms will be formalized into computer models that construct food webs. Webs constructed in this manner will be compared against empirically observed food webs. This comparison will indicate whether the simulated mechanisms deserve further analytical and experimental investigation as potential sources of food web patterns.