动物的行为产生因素来分，可分为______ 和______．
动物行为按获得途径不同可分为先天性行为和学习行为．先天性行为指动物生来就有的、由体内遗传物质决定的行为，对维持最基本的生存必不可少．而学习行为则是指在遗传因素的基础上，通过环境因素的作用，由生活经验和学习而获得的行为．一般来说，动物越高等，学习能力越强，适应环境能力也就越强，对生存也就越有意义．
故答案为：先天性行为；学习行为．
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| In my dual (双重的) profession 1 an educator and health care provider, I have worked with many children infected with HIV. They have taught me so many things, but I have especially learned that great 2 can be found in the smallest individuals. Let me tell you about Tyler. Tvler was 3 infected with HIV; his mother was also infected. From the very beginning of his life, he was dependent on medications to 4 him to survive. When he was five, he had a tube inserted in a vein (静脉) in his chest. At times, he also needed extra oxygen to support his 5 . Tyler wasn't 6 to give up one single moment of his childhood to this deadly disease. It was not 7 to find him playing and racing around his backyard, wearing his medicine-loaded backpack and 8 his tank of oxygen behind him in his little wagon (小推车). All of us who knew Tyler were impressed by his pure 9 in being alive and the energy it gave him Tyler's mom often 10 him by telling him that he moved so 11 she needed to dress him in red. That way, when she peered through the window to check on him playing in the yard, she could quickly 12 him. This deadly diseade eventually 13 down Tyler. He grew quite ill and, unfortunately, 14 did his HIV- infected mother. When it because 15 that he wasn't going to survive, Tyler's mom talked to him about 16 . She comforted him by telling Tyler that she was dying too and that she would be with him soon in heaven. A few days before his death, Tyler 17 to me to come to his hospital bed and 18 , "I might die soon. I'm not 19 . When I die, please dress me in 20 . Mom promised she's coming to heaven, too. I'll be playing when she gets there, and I want to make sure she can find me." | ||||
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