Realised hypothetical phenotypes and the adaptive value of Batesian mimicry

实现的假设表型和贝茨拟态的适应性价值

• 批准号: NE/S000623/1
• 负责人: Tom Reader
• 金额: $ 61.34万
• 依托单位: University of Nottingham
• 依托单位国家: 英国
• 项目类别: Research Grant
• 财政年份: 2019
• 资助国家: 英国
• 起止时间: 2019 至 无数据
• 项目状态: 未结题
• 来源: https://gtr.ukri.org/projects?ref=NE%2FS000623%2F1
• 关键词: Realised; hypothetical; phenotypes; adaptive; value

Many animals, such as venomous snakes or stinging wasps, advertise to potential predators that they are well defended by displaying bright, bold colour patterns. Other animals, known as "mimics", have evolved to deceive predators by displaying patterns similar to the dangerous "models", despite being harmless. Studying the evolution of mimicry has the potential to tell us much about how natural selection leads to adaptation in wild animals.Among mimics, we see many prominent and beautiful examples of the extreme adaptations that evolution can produce. However, some mimics, including many hoverflies that mimic wasps, only approximately resemble their model. We expect natural selection to favour the most convincing mimics, because less good ones ought to be recognised and picked off by predators: so why are some mimics inaccurate? Perhaps predators (such as birds) do not pay attention to all aspects of the prey's appearance, so the mimic does not have to be accurate in every way. Birds might avoid all prey that are roughly similar to a particularly nasty model, so beyond a certain point, further accuracy is unnecessary. Alternatively, the best chances of survival may gained by mimics which approximately resemble several nasty model species, rather than those which are perfect mimics of one particular model. To test these ideas, we need to know not only how successful existing mimics are, but also the performance of alternative mimics with different combinations of features to the existing ones. Would a more accurate mimic survive better? What if it were perfect except for its colour? This is an example of a more general problem in evolutionary biology, of predicting how non-existent, but theoretically plausible, organisms might perform in comparison to those that we observe in nature. To explore the evolutionary potential of mimics, our project brings together recently-developed technologies in a way never exploited before by biologists. First, we will photograph hoverflies and wasps from multiple angles and assemble 3D digital representations. We will then create new "morphed" images of plausible, but imaginary, intermediates between hoverflies and wasps which vary in similarity to the wasps. Thirdly, we will use 3D printing to create models of these intermediates (as well as the "real" insects) that are realistic in terms of their size, colour, pattern and shape. Lastly, we will measure the "survival" of these 3D models in a variety of experiments.We will test the response of predators by training birds to "attack" models of hoverflies, but avoid those of wasps, in order to gain food rewards. Having learnt that distinction, the birds will then be tested for how they behave towards 3D models of intermediate appearance. The longer the birds hesitate before attacking, the more effective is the mimicry, because in the wild such delays would give the insect an opportunity to escape. We will look at predator behaviour both in the wild, where natural communities of birds with varying levels of experience are foraging for food, and in the laboratory, where we can control the experiences of each individual and watch how they learn. We will also repeat the experiments using praying mantises in place of birds, to investigate whether insect predators judge mimicry differently. Our project addresses a long-standing biological question about the evolution of inaccurate mimicry, but will also provide broader insights into evolutionary processes. What is it about existing species that mean they survived when others either did not survive, or never evolved in the first place? This in turn allows us to understand how evolution produced the combinations of characteristics of existing species, and to predict the direction that evolution might take in the future. Our novel method will provide a framework for other evolutionary biologists to explore similar questions in a wide range of different organisms.

许多动物，例如毒蛇或螫黄蜂，通过展示明亮、大胆的颜色图案向潜在的捕食者宣传它们受到了很好的保护。其他被称为“模仿者”的动物已经进化到通过展示类似于危险“模型”的图案来欺骗捕食者，尽管它们是无害的。研究拟态的进化有可能告诉我们很多关于自然选择如何导致野生动物适应的信息。在拟态中，我们看到了进化可以产生的极端适应的许多突出而美丽的例子。然而，一些模仿者，包括许多模仿黄蜂的食蚜蝇，仅与它们的模型大致相似。我们预计自然选择会青睐最有说服力的模仿者，因为较差的模仿者应该被掠食者识别并捕获：那么为什么有些模仿者不准确呢？也许捕食者（例如鸟类）不会注意猎物外观的各个方面，因此模仿者不必在各个方面都准确无误。鸟类可能会避开所有与特别令人讨厌的模型大致相似的猎物，因此超过某一点，就不需要进一步的准确性。或者，最好的生存机会可能是通过与几种令人讨厌的模型物种近似相似的模仿者获得的，而不是那些完全模仿某一特定模型的物种。为了测试这些想法，我们不仅需要了解现有模仿的成功程度，还需要了解具有与现有模仿不同的特征组合的替代模仿的性能。更准确的模仿者会生存得更好吗？如果它除了颜色之外都是完美的怎么办？这是进化生物学中更普遍的问题的一个例子，即预测不存在但理论上合理的生物体与我们在自然界中观察到的生物体相比可能表现如何。为了探索拟态动物的进化潜力，我们的项目以生物学家以前从未利用过的方式汇集了最近开发的技术。首先，我们将从多个角度拍摄食蚜蝇和黄蜂，并组装 3D 数字表示。然后，我们将创建新的“变形”图像，这些图像是介于食蚜蝇和黄蜂之间的看似合理但虚构的中间体，与黄蜂的相似性有所不同。第三，我们将使用 3D 打印来创建这些中间体（以及“真正的”昆虫）的模型，这些模型在尺寸、颜色、图案和形状方面都很逼真。最后，我们将在各种实验中测量这些 3D 模型的“生存率”。我们将通过训练鸟类“攻击”食蚜蝇模型，但避开黄蜂模型来测试捕食者的反应，以获得食物奖励。了解了这种区别后，将测试这些鸟对中间外观 3D 模型的行为方式。鸟类在攻击前犹豫的时间越长，模仿就越有效，因为在野外，这种延迟会给昆虫逃跑的机会。我们将在野外观察捕食者的行为，在野外，具有不同经验水平的鸟类自然群落正在寻找食物，在实验室中，我们可以控制每个个体的经历并观察它们如何学习。我们还将用螳螂代替鸟类重复实验，以研究昆虫捕食者是否对拟态有不同的判断。我们的项目解决了一个长期存在的关于不准确模仿进化的生物学问题，但也将为进化过程提供更广泛的见解。当其他物种要么没有生存，要么从一开始就从未进化过时，现有的物种意味着它们能够生存下来，这意味着什么？这反过来又使我们能够了解进化如何产生现有物种特征的组合，并预测未来进化可能采取的方向。我们的新方法将为其他进化生物学家提供一个框架，以探索各种不同生物体中的类似问题。

项目成果

Body size in Batesian mimicry

贝茨拟态中的身体大小

• DOI: 10.1007/s10682-022-10204-6
• 发表时间: 2022
• 期刊: Evolutionary Ecology
• 影响因子: 1.9
• 作者: Taylor C