內在因素以及打鬥經驗如何共同影響個體攻擊性一致性

The influence of intrinsic factors and fighting experience on aggressive consistency

陳家平(Chen Chia-Ping)

指導教授 ： 許鈺鸚

國立臺灣師範大學/理學院/生命科學系/碩士(2019年)

https://doi.org/10.6345/THE.NTNU.SLS.008.2019.D01

摘要

動物經常藉由打鬥競爭有限的資源，但在打鬥的過程中會付出一些代價如時間和能量甚至會受傷及死亡。動物的打鬥行為會受到個體的內在因素(intrinsic factor)如年齡、體型、打鬥能力和荷爾蒙基礎值所影響。許多動物的行為在不同的時間地點會展現出一致性。除此之外，個體於打鬥行為中所獲得之獲勝和落敗經驗會提供個體評估自身打鬥能力的資訊，進而改變個體往後的打鬥行為。個體在得到獲勝經驗後，會展現出較高的攻擊性及獲勝機率(勝者效應，winner effect)，而在經歷過落敗經驗後則會有較低的攻擊性及獲勝機率 (敗者效應，loser effect)。然而打鬥提供的資訊的影響可能會因個體內在因子有所不同，因而呈現不同強度的勝者/敗者效應。依據打鬥經驗來改變自身的攻擊性對於個體有重大的影響。但獲勝/落敗經驗是否會影響個體攻擊性一致性以及影響的時間長短目前尚不清楚，而這樣的影響是否也會因為個體的內在因子而有所不同? 本研究以紅樹林鱂魚(Kryptolebias marmoratus)為實驗物種。先以相近體長配對進行打鬥，以檢測其打鬥能力後，分別給予實驗物種獲勝經驗、落敗經驗或者控制(無打鬥)經驗處理。每次經驗處理前、處理後1天以及處理後4週皆以鏡像測試測量實驗個體的攻擊性。本研究結果顯示：(1)打鬥能力較佳的個體具有較高的攻擊性；(2)年齡越大/體型越大的個體在獲得打鬥經驗後與年齡較小/體型較小的個體相比有較慢的攻擊延遲時間；(3)個體展現出經驗效應，其中觀察到明顯的勝者效應，但沒有觀察到敗者效應；(4)個體在短期(1天)以及長期(4週)內都展現出攻擊性的一致性；(5)個體在獲得獲勝經驗後雖然會改變攻擊性，但並不會影響個體攻擊性的一致性；(6)年齡較小以及經驗前睪固酮濃度較高的的個體在獲得打鬥經驗後，攻擊性較具有一致性。

關鍵字

攻擊性 ； 一致性 ； 經驗效應 ； 紅樹林鱂魚

並列摘要

Animals fight for limited resources. Fighting behavior would be influenced by intrinsic factors like fighting ability, body size and hormonal state of the individual. Recent studies show that individuals usually behave consistently over time and in different contexts. Besides, winning and losing experience would provide information about individuals’ fighting ability and change their fighting behavior. It can also be affected by the outcomes of the individual’s previous fights: winning and losing experiences tend to increase and lower an individual’s aggressiveness and chances of winning subsequent fights, respectively (winner and loser effects). However, the importance of winning/losing experiences might depend on the intrinsic factors of individuals.Winner and loser effect would change an individual’s aggressiveness but there is no experiment has proof that whether and how winner and loser effects would influence individual’s aggressive consistency, and whether the influence of winning/losing experiences is dependet on individuals’ intrinsic factors.
I used K. marmoratus as the study animal. I first divided the fish into better and worse fighters by staging size-matched contests. Then I randomly assign individuals to 3 experience treatments (winning, losing and no recent contest experience). I measure the aggressiveness of the fish, before and after the experience treatments (1 day after and 28 days after) by recording the attack behaviors that the fish deliver to their mirror images.
The result showed that: (1) Better fighters behaved more aggressiveness than worse fighters; (2) Older/larger individuals attacked slower; (3) Winning (but not losing) experience affected the fish’s aggressiveness; (4) Individuals showed consistency in their aggressiveness in both one-day-period and four-week-period; (5)Winning increased individuals’ aggressiveness but didn’t influence aggressive consistency of individuals; (6) Younger and individuals at higher testosterone level showed more aggressive consistency after receving fighting experience.

並列關鍵字

aggressiveness ； consistency ； experience effect ； Kryptolebias marmoratus

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