許鈺鸚Yuying Hsu黃暐霖Wei-Lin Huang2019-09-052014-2-272019-09-052014http://etds.lib.ntnu.edu.tw/cgi-bin/gs32/gsweb.cgi?o=dstdcdr&s=id=%22GN0699430230%22.&%22.id.&http://rportal.lib.ntnu.edu.tw:80/handle/20.500.12235/104388動物經常為了競爭有限的資源而打鬥，許多研究發現，當擁有資源之個體與未擁有資源的入侵者打鬥時，資源擁有者的攻擊傾向以及獲勝機率往往高於入侵者。這些結果可能是(1)擁有資源使個體的攻擊性提高，(2)入侵者在面對資源擁有者時攻擊性下降，或是(3)兩者同時發生所造成。本研究利用紅樹林鱂魚(Kryptolebias marmoratus)喜好躲藏於遮蔽物中且具有高攻擊性的特性，探討資源(遮蔽物)如何影響打鬥雙方的行為。實驗分為三個處理組：(1)單方資源組－提供遮蔽物給打鬥雙方其中一方，(2)雙方無資源組－不提供遮蔽物給打鬥任一方，(3)雙方資源組－分別提供遮蔽物給打鬥雙方。實驗結果顯示，打鬥雙方攻擊性的差異會因為資源擁有者於打鬥開始時是否在遮蔽物內而有所不同。只提供遮蔽物給打鬥雙方其中一方時(單方資源組)，若打鬥開始時擁有者在遮蔽物內，則其攻擊性與獲勝機率皆較無資源的入侵對手來的高；但若擁有者在遮蔽物外，擁有者與入侵者之行為差異則不顯著。進一步分析顯示，在遮蔽物內與在遮蔽物外的擁有者之攻擊性無顯著差異；然而，入侵者在面對遮蔽物內之擁有者時，攻擊性顯著較低。這些結果顯示擁有者的攻擊性與其打鬥開始時所在的位置無關，但是其所在位置卻會影響對手的攻擊性。此外，比較單方資源組與雙方無資源組則發現，(1)不論是否於打鬥開始時剛好在遮蔽物內，資源擁有者的攻擊性皆顯著上升；(2)入侵者只有在面對在遮蔽物內的資源擁有者時，攻擊性才會顯著下降。而雙方資源組之打鬥顯示，當打鬥雙方皆為資源擁有者時，雙方之攻擊性不受對手是否在遮蔽物內的影響。此研究之結果顯示遮蔽物會提升資源擁有者的攻擊性，而且在特定的狀況(打鬥開始時擁有者正好在遮蔽物內)並會降低入侵者對手的攻擊性。這些結果顯示紅樹林鱂魚可能藉由觀察對手是否由遮蔽物游出來判斷其是否真為遮蔽物擁有者，以決定打鬥決策。Animals often fight with each other to compete for limited resources. Numerous studies have shown that resource owners tend to behave more aggressively and win more contests than intruders. These trends could result from (1) resources causing owners to behave more aggressively, (2) intruders behaving less aggressively when fighting owners or (3) a combination of both. Here, I used an aggressive mangrove killifish, Kryptolebias marmoratus to examine the importance of individuals’ ownership status to the contest decisions of the individual and its opponent. I provided a shelter to one of the contestants of a pair (type I: owner vs. intruder), neither contestant (type II: non-owner vs. non-owner) or both contestants (type III: owner vs. owner), and then staged a contest between them. The contest interactions between owners and non-owners (in type I contests) were influenced by whether or not the shelter owner was inside the shelter at the contest start. Owners that were in their shelters at the contest start showed a greater tendency to fight and won more contests than their opponents; those outside the shelter at the start did not. Further analyses showed that owners’ position at the start of the contest (inside or outside the shelter) did not affect the owners’ own aggressiveness, but did affect that of their non-owner opponents: non-owners were less aggressive when faced with owners inside shelters. Analyses of the contestants’ behavior in type I and II contests showed that (1) shelter owners had a higher tendency to fight than non- owners whether or not they were in their shelters at the start, and (2) intruder had a lower tendency to fight than non-owners only against owners that were inside the shelter at the start. Furthermore, contestants’ behavior in type III contests showed that shelter owners’ tendency to fight never decrease, even though they against another shelter owner that were inside the shelter at the start. Overall, these results demonstrate (1) that ownership status influences both owners’ and intruders’ contest decisions (in opposite directions), producing a detectable ownership advantage and (2) that intruders require confirmation of their opponents’ ownership status before retreating without challenging them. Ownership status per se is therefore important to the fish’s contest decisions.遮蔽物資源擁有權入侵者攻擊性Kryptolebias marmoratusshelterownership statusintruderaggressionKryptolebias marmoratus