Genome size of termites (Insecta, Dictyoptera, Isoptera) and wood roaches (Insecta, Dictyoptera, Cryptocercidae).
The evolution of genome size has been discussed in relation to the evolution of various biological traits. In the present study, the genome sizes of 22 dictyopteran species were estimated by Feulgen image analysis densitometry and 6-diamidino-2-phenylindole (DAPI)-based flow cytometry. The haploid genome sizes (C-values) of termites (Isoptera) ranged from 0.58 to 1.90 pg, and those of Cryptocercus wood roaches (Cryptocercidae) were 1.16 to 1.32 pg. Compared to known values of other cockroaches (Blattaria) and mantids (Mantodea), these values are low. A relatively small genome size appears to be a (syn)apomorphy of Isoptera + Cryptocercus, together with their sociality. In some phylogenetic groups, genome size evolution is thought to be influenced by selective pressure on a particular trait, such as cell size or rate of development. The present results raise the possibility that genome size is influenced by selective pressures on traits associated with the evolution of sociality.
Koshikawa
Shigeyuki
S
Graduate School of Environmental Science, Hokkaido University, Sapporo 060-0810, Japan. koshi@ees.hokudai.ac.jp
Miyazaki
Satoshi
S
Cornette
Richard
R
Matsumoto
Tadao
T
Miura
Toru
T
D000818:Animals; D020048:Blattellidae / Q000145:classification / Q000235:genetics / Q000254:growth & development; D003058:Cockroaches / Q000145:classification / Q000235:genetics* / Q000254:growth & development / Q000502:physiology; D004396:Coloring Agents; D004247:DNA / Q000235:genetics*; D005434:Flow Cytometry; D016678:Genome; D020049:Isoptera / Q000235:genetics* / Q000254:growth & development / Q000502:physiology; D010526:Periplaneta / Q000235:genetics / Q000254:growth & development; D010802:Phylogeny; D012919:Social Behavior; D013045:Species Specificity
D004396:Coloring Agents; D004247:DNA