種內合作如何與資源共同影響族群動態

Cooperation and lateral forces: moving beyond bottom-up and top-down drivers of animal population dynamics

陳映妤(Ying-Yu Chen)

指導教授 ： 沈聖峰

國立臺灣大學/生命科學院/生態學與演化生物學研究所/碩士(2020年)

https://doi.org/10.6342/NTU202001116

摘要

生態學家早已知道，動物的族群動態是由上行力（bottom-up forces）（例如資源可利用性）和下行力（top-down forces）（例如捕食）所共同決定的。然而，一些經濟學家指出人口動態也受到合作的影響，這是生態學家很少考慮的概念。在這裡，我們透過建構將環境條件、合作和族群大小結合在一起的個體為本模式（individual-based model），來考慮「橫向力量」（例如作用於族群內的種間合作）對族群動態的作用。在證明環境質量同時影響合作和資源可利用性之後，我們發現由於資源可利用性對合作和族群大小的對比影響，在中等資源水平下社會性生物的族群大小會大於非社會性生物。最終，我們的結果顯示，社會性族群比非社會性族群對環境變化的適應力更強，這是因為合作的好處可能大於資源匱乏的影響。在氣候變化時代，了解環境如何影響包括我們自己在內的社會物種的族群動態至關重要。

關鍵字

合作 ； 族群動態 ； 恢復力

並列摘要

Ecologists have long known that animal population dynamics are determined by a combination of bottom-up (resource availability) and top-down forces (predation). However, some economists have shown that human population dynamics are also influenced by cooperation, a concept seldom considered by ecologists. Here we consider the role of “lateral forces” on population dynamics by constructing an individual-based model linking environmental conditions, cooperation, and population size. After showing that environmental quality influences both cooperation and resource availability, we find that sizes of social populations will be greater than those of non-social populations under intermediate resources levels due to the contrasting effects that resource availability has on cooperation and population size. Ultimately, we show that social populations are more resilient to environmental change than non-social ones because the benefits of cooperation can outweigh the effects of low resource availability. Understanding how the environment influences population dynamics of social species, including our own, is critical in era of climate change.

並列關鍵字

cooperation ； population dynamics ； resilience

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