RT Journal
A1 Gregory, T. Ryan
A1 Hebert, Paul D.N.
T1 The Modulation of DNA Content: Proximate Causes and Ultimate Consequences
JF Genome Research 
JO Genome Research 
YR 1999 
FD April 01 
VO 9 
IS 4 
SP 317 
OP 324 
DO 10.1101/gr.9.4.317 
UL http://genome.cshlp.org/content/9/4/317.abstract 
AB The forces responsible for modulating the large-scale features of the genome remain one of the most difficult issues confronting evolutionary biology. Although diversity in chromosomal architecture, nucleotide composition, and genome size has been well documented, there is little understanding of either the evolutionary origins or impact of much of this variation. The 80,000-fold divergence in genome sizes among eukaryotes represents perhaps the greatest challenge for genomic holists. Although some researchers continue to characterize much variation in genome size as a mere by-product of an intragenomic selfish DNA “free-for-all” there is increasing evidence for the primacy of selection in molding genome sizes via impacts on cell size and division rates. Moreover, processes inducing quantum or doubling series variation in gametic or somatic genome sizes are common. These abrupt shifts have broad effects on phenotypic attributes at both cellular and organismal levels and may play an important role in explaining episodes of rapid—or even saltational—character state evolution.