【摘 要】
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科学家们一度认为成年脊椎动物是不可能改变身体长度的,但是现在他们发现生活在加拉帕戈斯群岛的海鬣蜥就有这种能耐,它可以将身体放大或缩小20%。经过18年的研究之后,科学
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科学家们一度认为成年脊椎动物是不可能改变身体长度的,但是现在他们发现生活在加拉帕戈斯群岛的海鬣蜥就有这种能耐,它可以将身体放大或缩小20%。经过18年的研究之后,科学家们发现个头大的海鬣蜥比个头小的收缩程度大,而对于同样大小的海鬣蜥来说,雌性收缩程度较大。当厄尔尼诺现象发生时,它们的身体缩得最厉害,因为此时它们的食物来源得不到保障。这一时期收缩程度大的海鬣蜥比个头大的同类活得更长。
Scientists once thought it impossible for adult vertebrates to change their body length, but now they find the sea iguana, which lives in the Galapagos Islands, capable of scaling the body up or down by 20%. After 18 years of research, scientists have found that big marine iguanas have a smaller degree of contractions than their heads, while females contract more for the same size of marine iguanas. When the El Niño phenomenon occurs, their body shrinks the most because their food sources are not guaranteed at this time. The sea iguanas, which had a large contraction during this period, lived longer than their larger counterparts.
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