費洛蒙為生物體產生的化學物質，會以不同的形式排出體外形成痕跡，並由同種及異種間利用。而陸生腹足綱痕跡追隨的目的，大致上來說具有群聚、交配，捕食、回巢及節省能量等功能。我利用兩種壽山常見的陸生蝸牛，分別為雌雄同體的小菱蝸牛(Satsuma succincta)，及雌雄異體的皺大山蝸牛(Cyclophorus friesianus) 進行追隨實驗。本研究提出三個問題：(1) 這兩種陸生蝸牛是否也具有同種間的追隨行為，(2)追隨行為是利用何種化學物質進行追隨，以及(3)雌雄異體的物種是否可藉由此行為作為交配策略。每次測試皆由兩隻同種之蝸牛組成：一隻作為遺留黏液之marker，另一隻為追隨黏液之tracker。結果發現兩物種皆出現追隨行為，且室內與室外的結果沒有顯著差異。小菱蝸牛同時出現黏液及以氣味追隨的行為，但以氣味作為主要的化學訊號；皺大山蝸牛則單純以黏液追隨。在性別差異的實驗中，皺大山蝸牛在異性間與同性間的追隨頻率雖然沒有顯著差異，但出現異性高於同性的傾向，且雄性追隨雌性的頻率略高於其他性別配對。雖然無法支持黏液追隨可作為交配策略，但高程度的重疊比例下，推測黏液追隨的功能可為減少移動能量的耗損達到省能的目的。

Pheromone is produced by animals and secreted in variously ways to form trails which can be used by conspecifics or between species. The functions for trail-following in terrestrial gastropod are aggregating, mating, predating, homing and energy saving. In this study, I used two species of terrestrial gastropod, Satsuma succincta and Cyclophorus friesianus, which are abundance in Mt. Shoushan, Kaohsiung, Taiwan to test three questions: (1) Do these land snails follow the chemical trail laid by conspecifics? (2) If followed, what kind of chemical trail would they follow? (3) Whether trail-following is a mating strategy for dioecious species? Every following behavior test I used two snails, marker for leaving trail and tracker for following trail. Both of the two species showed trail-following behavior, and there were no difference between two studying areas. S. succincta had trail-following behavior both by mucus and odor, but odor was the main chemical cue for C. friesianus. In test for sexual difference on trail-following behavior, although there were no significant difference between the different and same sex groups, the frequency was higher in different sex group and female followed by male was higher than other sexual combining pairs. This test supported that mucus trail-following might be a purpose for energy saving due to the trail overlapped about half of the marker’s trail.

中文摘要 i
Abstract ii
Contents iii
Introduction 1
Materials and Methods 5
Results 10
Discussion 13
Literature Cited 17
Tables 21
Figures 24

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