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很早以前,人们就注意到野生动物的寿命比家养动物的寿命长;例如野兔的平均寿命为15年,而家兔的寿命只有4—5年;象在野外可以生活200年,而驯化的象只能活80年。这是什么缘故呢?原来,野生动物寿命较长的重要原因之一,在于它们为了获取食物或逃避敌人,经常在原野上奔驰,活动量比较大;而家养或驯化了的动物活动量减少很多。因此寿命较短。值得重视的是,科学家们还发现家养动物的心脏重量与体重之比低于野生动物。例如家兔的心肌重量
Long ago, people noticed that wildlife lived longer than domestic animals. For example, the average life expectancy of rabbits was 15 years, while that of rabbits was only 4-5 years. As in the wild, they lived for 200 years, while domestication Like can only live 80 years. What is the reason? It turned out that one of the important reasons for the longer life expectancy of wild animals is that they frequently drive on wilderness in order to obtain food or evade their enemies, resulting in a large amount of activity; while the number of domesticated or domesticated animals has been greatly reduced . So shorter life expectancy. It is worth noting that scientists also found that the domestic animal’s heart to body weight ratio is lower than the wildlife. For example, rabbit’s myocardial weight