每當遷徙季節一到，成千上萬的鳥類將成群結隊地飛往牠們的目的地；其中最令人感到不可思議的地方，就是牠們有如GPS (global positioning system)一般優良的導航能力。從鳥類的行為實驗上來看，鳥類導航所利用的方法可能有很多種，我們無法辨別牠們究竟是利用什麼方法來感知方向資訊；不過，由於鳥類的磁感(magnetoreception)已經在許多的實驗中被證實，因此有許多人認為鳥類辨別方向的能力是來自於地球磁場所提供的訊息。其中，有一個以量子力學為基礎的理論認為，地球磁場會間接影響鳥類體內自由基對的化學反應，進而影響鳥類的飛行方向；我們將這個化學磁感理論稱為自由基對機制(radical pair mechanism)。本篇論文的主要目的，就是根據已知的自由基對機制理論，建立出一個可以在Matlab環境下進行模擬的簡化模型，並討論模擬結果與鳥類行為之間的關聯性。

When the season of migration comes, there are thousands of birds flying in flocks to the destination. The most inconceivable thing is that, their ability of navigation is excellent, just like the GPS(global positioning system). On the view of the bird’s behavioural experiments, birds probably have so many kinds of skill to navigate that we can’t recognize what exactly skill they use to perceive the information of direction. But, bird’s magnetoreception has been proven by many provided experiments. Some researchers believed that the ability birds find out the directions comes from the information of geomagnetic field. There is a theory, which is based on Quantum Mechanics, suggested that the geomagnetic field affects the chemical interactions of radical pairs in birds indirectly, and hence affects the orientation of birds. This chemical magnetoreception theory is called radical pair mechanism. In this thesis, our main purpose is, according to the existing theory, to establish a simplified model which can be simulated in Matlab, and to discuss the relation between the simulation results and bird’s behaviour.
Key Words: quantum biology, bird’s migrating, bird’s navigation, radical pair mechanism

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