溫度敏感的任務分配決定了一種社會性昆蟲的複雜問題解決

Temperature-sensitive task allocation determines the complex problem solving of a social insect species

李憶晴(Yu-Ching Li)

指導教授 ： 沈聖峰

國立臺灣大學/理學院/氣候變遷與永續發展國際學位學程/碩士(2021年)

https://doi.org/10.6342/NTU202101868

摘要

目前已有許多研究表明氣候變遷影響了生物的物候、分布和物種間的交互作用，然而，我們對於氣候變遷如何影響社會生物的合作與衝突行為卻只有非常有限的了解。部分研究結果發現暖化可能促進合作，而另一些研究卻發現暖化可能導致衝突加劇。這些研究結果難以整合成單一的通則，很可能是因為過去的研究多半只考慮了環境因子和社會行為之間的關聯性，而忽略了物種交互作用和資源品質在其中的影響。
我們使用亞洲的埋葬蟲Nicrophorus Nepalensis作為研究物種，用以探討氣候變遷如何影響社會生物。埋葬蟲以小型脊椎動物的屍體作為繁殖的資源，同時面臨其他物種的競爭。埋葬蟲群體間的社會行為會影響處理屍體的效率。我們在不同的溫度下設置一個簡單的迷宮，並且使用經過蛆處理的老鼠屍體作為埋葬蟲的繁殖資源。在蛆蟲的競爭壓力下，埋葬蟲需要清理屍體並且將其拖曳到正確的位置埋葬。我們記錄實驗過程中埋葬蟲的社會行為、屍體移動路徑和繁殖結果，並且分析各項因素之間的影響。
我們的研究發現，環境溫度僅升高1°C就足以改變埋葬蟲的合作行為，以及他們投資在不同任務的優先順位。在較高的溫度下，合作處理屍體可以有效的抵抗來自麗蠅的競爭壓力。然而，這同時對搬運屍體的任務造成了負面影響，因為拖動屍體是一項難以協調合作的任務，參與者越多反而容易阻礙彼此而降低效率。這顯示了暖化影響社會生物的機制比過往研究所討論的更加複雜。因此，暖化對社會生物的影響還需要仔細考量合作行為能夠多有效的解決暖化對資源帶來的挑戰，以及不同任務之間的如何相互影響。

關鍵字

任務分配 ； 複雜問題解決 ； 合作生殖 ； 埋葬蟲 ； 氣候變遷 ； 社會行為

並列摘要

Many biological studies have shown that climate change affects the phenology, distribution, and interactions between species. However, we have only a very limited understanding of how climate change affects the cooperative and conflict behaviors of social organisms. Warming may promote cooperation in some cases, while other studies have shown that warming may result in increased social conflict. Past studies have only considered the correlation between environmental factors and social behavior, while other factors such as species interactions and resource quality are missing. Because of this, it is difficult to integrate the results of these studies into a universal rule.
Here, we used the social Asian burying beetle Nicrophorus Nepalensis to study how climate change affects social organisms. Burying beetles use vertebrate carcasses as a sole resource for breeding, and bury beetles also face intense competition from other species. The social behavior of bury beetles affects the efficiency of preparing carcass. We placed a simple maze at different temperatures and provided maggot-treated rat carcasses for the bury beetles to breed. Under the pressure of competing maggots, the bury beetles need to clean the carcasses and drag them to the correct location for burial. Experiments were conducted to observe the social behavior, dragging paths and reproduction results of the bury beetles and to analyze the effects of each factor.
Our research has found that warming by 1°C changes the cooperative behaviors of social burying beetles, as well as their priority of investing in different tasks on group resources. In our study, cooperative preparation of carcasses at warmer temperatures can be an effective way to counteract the competitive pressures of blowflies at higher temperatures. However, it also has negative effects on the task of transporting the carcass to the suitable burial sites, which is a difficult task to coordinate and thus inevitably becomes less efficient with more individuals. It shows that the mechanisms by which warming affects social organisms are even more complex than what has been discussed in previous studies. Thus, the effects of warming on social organisms must carefully consider the extent to which cooperative behavior is effective in addressing the challenges posed by temperature changes to resources, and the interactions between different tasks performed at different temperatures.

並列關鍵字

task allocation ； complex problem-solving ； cooperative breeding ； burying beetles ； climate change ； social behavior

參考文獻

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