Collaborative Research: Effects of a Regional Plio-Pleistocene Extinction Event on the Escalation of Predator-Prey Interactions

随着人类继续通过物种的丧失、栖息地的破碎和物种的全球再分配来改变世界的生态系统，我们正在越来越多地重新创造与过去物种灭绝相似的环境。物种将如何应对环境的变化？如果我们要管理和预测人类引起的环境变化的长期后果，关于在特定类型的环境和危机后的选择性制度中，哪些适应性解决方案最有效的信息，对于特定谱系、特定栖息地和受区域限制的信息至关重要。为了更好地理解生态损失对物种相互作用的影响，pi计划测试升级假设，该假设声称，随着生物危害变得更加严重，对这些危害的适应增加了表达。这项研究将集中在佛罗里达上新世-更新世的大量化石记录中，在上新世末期区域性大灭绝事件前后，与海螺（Strombus alatus complex的蜗牛）和它们的螃蟹捕食者进行斗争。鉴于对捕食压力的变化如何影响对敌人的适应的基本理论理解，以及先前关于捕食水平在上新世达到顶峰并在灭绝事件发生后的更新世下降的推断，预计在上新世之后，海螺和螃蟹之间的战斗升级已经放缓或停止。为本提案收集和研究的材料也将用于发展实践、探究性的进化论教学活动。特别是，结合国家科学教育标准，向中学生介绍化石作为生物进化和环境变化的记录，贝壳作为捕食者-猎物关系和适应的记录的概念。

As humans continue to transform the world's ecosystems through the loss of species, fragmentation of habitats and global redistribution of species, we are increasingly re-creating conditions not unlike those of past extinctions. How will species respond to such changes in their environment? Lineage-specific, habitat-specific, and regionally constrained information on what adaptive solutions work best in particular kinds of environments and selective regimes in the aftermath of crises is critical if we are to manage and anticipate the long-term consequences of human-induced environmental changes. Towards this goal of better understanding the effects of ecological losses on species interactions, PIs plan to test the hypothesis of escalation, which claims that as biological hazards become more severe adaptations to those hazards increase in expression. The study will focus on fighting conchs (snails of the Strombus alatus complex) and their crab predators in the abundant fossil record of the Plio-Pleistocene of Florida before and after a regional mass extinction event at the end of the Pliocene. Given a basic theoretical understanding of how changes in predation pressure should affect adaptation to enemies, and the previous inference that levels of predation peaked in the Pliocene and declined in the Pleistocene following the extinction event, escalation between fighting conchs and crabs is predicted to have slowed or halted after the Pliocene. The material that will be collected and studied for this proposal will also be used to develop hands-on, inquiry-based activities for teaching about evolution. In particular, secondary school students will be introduced to the concepts of fossils as records of biological evolution and environmental change, and shells as records of predator-prey relationships and adaptation, connecting to a number of National Science Education Standards.