Subterranean Fishes of the World

4848

1972

The American Naturalist

621-644

106

Typhlogobius californiensis 1.2 picograms haploid DNA content

The assessment of evolutionary relationships among organisms has pri- marily involved morphological criteria. Recently, biochemical techniques have also come to play an important role. Several of these teclhniques have been applied to the fishes, such as studies of protein similarities (Markert and Faulhaber 1965 Bailey et al. 1970; Wolf et al. 1969) and the ilieasure- lmenlt of cellular DNA content (Mirsky and Ris 1951; Ohno, Wolf, and Atkin 1968; Hinegardlner 1968). In general, this work confirms the phylo- genetic relationships that were determined by older methods. But more important, the biochemical techniques provide new insights into the nature of the evolutionary process. It has been shown in a previous paper (Hinegardner 1968) that highly specialized fishes tend to have less DNA per cell than the more generalized, or less evolved, fishes of the same phyletic grouping. The present paper further amplifies this correlation ald presents other aspects of fish evolution that correlate with cellular DNA content. This work is based on data gat-hered fromt assays of 275 different. species of fishes and is part of an overall survey of cellular DNA content in the animal kingdom.

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