Stevenson R D, Hill M F, Bryant P J
Department of Biology, University of Massachusetts, Boston 02125-3393.
Proc Biol Sci. 1995 Feb 22;259(1355):105-10. doi: 10.1098/rspb.1995.0016.
The importance of body size in predicting many aspects of an animal's biology has become well established in recent years. However, little is known about how body size evolves at the cellular level. Some published data suggest that it is cell number and not cell size that accompanies changes in organ and body size across taxa. We examined organ and cell allometry in the wing, eye and basitarsus of adult Hawaiian Drosophila, ranging in body length from 0.2 mm to 0.8 mm. Linear measurements of all three structures exhibit a positive allometry with body length. Exponents of the allometric equation were 0.96, 0.55 and 1.50 for wing, eye and basitarsus, respectively. Surface markers were used to quantify cell size of each organ. The allometric exponents for cell size as a function of organ size were 0.53, 0.68 and 0.33 for wing, eye and basitarsus, respectively. In contrast to reports in the literature on other systems, our results for Hawaiian Drosophila indicate that cell size may contribute between one third and two thirds to evolutionary changes in organ and body size.
近年来，体型在预测动物生物学诸多方面的重要性已得到充分确立。然而，关于体型在细胞水平上如何演化却知之甚少。一些已发表的数据表明，在不同分类群中，伴随器官和体型变化的是细胞数量而非细胞大小。我们研究了成年夏威夷果蝇翅膀、眼睛和基跗节的器官及细胞异速生长情况，这些果蝇体长从0.2毫米到0.8毫米不等。这三种结构的线性测量结果均与体长呈正异速生长关系。翅膀、眼睛和基跗节的异速生长方程指数分别为0.96、0.55和1.50。使用表面标记来量化每个器官的细胞大小。翅膀、眼睛和基跗节的细胞大小相对于器官大小的异速生长指数分别为0.53、0.68和0.33。与关于其他系统的文献报道不同，我们对夏威夷果蝇的研究结果表明，细胞大小可能在器官和体型的进化变化中贡献三分之一到三分之二的作用。
