1. Many species interactions occur along a continuum from mutualistic to antagonistic. Among these interactions, the effects of seed‐dispersing granivores (synzoochory) are especially interesting because the benefits and costs are so striking.
2. Here, we respond to a commentary by C. M. Moore and J. W. Dittel (‘On mutualism, models, and masting: the effects of seed‐dispersing animals on the plants they disperse’). We focus on the points that were most thought‐provoking to us, specifically the notions that (a) synzoochory is widespread, and therefore ought to be beneficial for plants, (b) dispersal should reduce negative density dependence and (c) plant life spans are at least an order of magnitude longer than typical study lengths.
3. We argue that (a) widespread occurrence of an interaction cannot serve as an argument that this interaction is mutualistic, (b) dispersal effects on density dependence are variable and need to be tested for every particular species pair and (c) Short‐term studies can be used to gain mechanistic understanding of interactions even without risky long‐term extrapolations.
4. Synthesis. Evaluating the costs and benefits of synzoochory for plant populations under different ecological contexts will help to understand the ecological principles of the interaction but also allows to move the interaction towards each end of the antagonism–mutualism continuum in nature management and conservation.

中文翻译：

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关于需要评估植物群的共生成本和收益

1. 许多物种的相互作用沿着从互惠到对立的连续过程发生。在这些相互作用中，种子分散食草动物（同食动物）的效果特别有趣，因为其收益和成本是如此惊人。
2. 在这里，我们回应CM Moore和JW Dittel的评论（“关于共生，模型和桅杆：种子散布动物对它们散布的植物的影响”）。我们专注于最发人深省的观点，特别是以下概念：（a）食道很广，因此对植物有益；（b）分散应减少负密度依赖性；（c）植物寿命比典型研究长度至少长一个数量级。
3. 我们认为（a）相互作用的广泛发生不能作为这种相互作用是互惠的论据，（b）对密度依赖性的分散效应是可变的，需要针对每个特定物种对进行测试，以及（c）短期研究即使没有风险的长期推断，也可以用来获得对相互作用的机械理解。
4. 综合。对不同生态环境下植物种群的共生动物的成本和收益进行评估，将有助于理解相互作用的生态学原理，但也可以使相互作用朝着自然管理和保护中的对抗－相互主义连续体的每一端发展。