EAGER: Poison Frogs and Toxic Arthropods – Diversification and parallel evolution of frog predators with their alkaloid-bearing prey

毒蛙的皮肤里有有毒物质，但它们自己不会产生这些化学物质。相反，它们从它们的节肢动物食物——蚂蚁和螨虫中获取这些毒液。在这些青蛙身上发现了800多种不同的化学物质。然而，蚂蚁和螨虫的多样性如此之大，以至于了解毒蛙如何从它们的节肢动物食物中获取毒素仍然是一个谜。这个项目将研究青蛙捕食者和有毒节肢动物之间的联系，这些节肢动物的价值更多的是由它们所含的毒素而不是它们的营养价值。该项目将研究有毒节肢动物及其毒蛙捕食者的多样性、遗传和进化。该项目的相关性在于发现新的知识，然后与社区分享，以促进我们对南美热带雨林等超级多样性地区的了解。这项基础研究将深入了解毒素在自然生态系统中是如何循环的。研究团队（圣约翰大学，欧洲和拉丁美洲的合作伙伴）将为STEM中代表性不足的群体提供学习经验，为纽约及其他地区的学生举办研讨会，并为公众举办公开讲座。SJU是美国最具民族多样性的县中心的一所大学，少数民族学生集中在这里。这项工作将包括对这些学者进行热带生态学、基因组学和生物信息学方面的培训。毒蛙的化学防御机制有充分的证据证明其饮食起源。然而，关于将有毒节肢动物基地与它们的毒蛙消费者联系起来的功能、系统基因组生物多样性和生态过程，人们知之甚少。这种防御在营养链中的移动需要相互作用的物种之间复杂的联系生态系统。为了回答这个问题，这个项目研究了一个以营养链的一部分为中心的模型系统，包括毒蛙和它们含生物碱的节肢动物饮食。该项目涉及两个主要的进化和生态维度：(1)毒蛙及其食物蚂蚁和螨虫的系统发育学和生物碱多样性；(2)转录组学、生理适应和进化平行性，这是由毒蛙及其有毒节肢动物食物中生物碱吸收起源之间的差异基因表达所证明的。这些目标将探讨在生物积累、差异基因表达和基因多样化的背景下，毒蛙及其有毒节肢动物的并行性、共同进化/共同多样化和趋同是如何进化的。这样的比较将有助于在新热带生物多样性群落中对防御性毒素循环的理解达到一个新的水平。拟议的研究将在一些最受威胁的生态系统，可可豆和亚马逊热带森林中使用涉及化学防御的捕食者-猎物动态，那里的生物多样性每天都在丧失。该奖项反映了美国国家科学基金会的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。

Poison frogs have venomous substances in their skins, but they do not produce these chemicals on their own. Instead, they harvest these venoms from their arthropod diet: ants and mites. More than 800 different chemicals were found in these frogs. However, the diversity of ants and mites is so vast that understanding how poison frogs gain toxins from their arthropod food remains a mystery. This project will examine the connection between frog predators and toxic arthropods, which are valued more by the toxins they contain than by their nutritional value. This project will examine the diversity, genetics and evolution of toxic arthropods and their poison frog predators. The relevance of this project resides on the discovery of new knowledge that can then be shared with the community to advance our understanding of megadiverse regions like the South American rain forest. This basic research will provide insights into how the recycling of toxins occurs in natural ecosystems. The research team (St. John’s University, European and Latin-American partners) will provide learning experiences to underrepresented groups in STEM with workshops for students and open lectures for the public in NYC and beyond. SJU is an institution in the heart of the most ethnographically diverse county in the US with a large concentration of minority students. This work will involve training these scholars in tropical ecology, genomics and bioinformatics.Chemical defenses in poison frogs have a well-documented dietary origin. Yet little is known about the functional, phylogenomic biodiversity and ecological processes that connect the toxic arthropod base with their poison frog consumers. The movement of such defenses in trophic chains requires an intricate ecosystem of connections among interacting species. To answer this question, this project examines a model system centered on a section of the trophic chain that includes poison frogs and their alkaloid-bearing arthropod diet. The project addresses two major evolutionary and ecological dimensions: (1) phylogenomic and alkaloid diversities across poison frogs and their dietary ants and mites and (2) transcriptomics, physiological adaptations and evolutionary parallelisms evidenced by differential gene expression among the origins of alkaloid sequestration in poison frogs and their toxic arthropod diet. These goals will address how parallelisms, coevolution/codiversification and convergence evolved in poison frogs and their toxic arthropod under the context of bioaccumulation, differential gene expression and gene diversification. Such comparisons will contribute to a new level of understanding of the cycling of defensive toxins across biodiverse Neotropical communities. The proposed research will use predator-prey dynamics involving chemical defenses in some of the most threatened ecosystems, the Chocoan and Amazonian tropical forests, where biodiversity is being lost daily.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.