TY - JOUR
T1 - Reproductive organ development along the caste differentiation pathways in the dampwood termite Hodotermopsis sjostedti
AU - Oguchi, K.
AU - Shimoji, H.
AU - Hayashi, Y.
AU - Miura, T.
N1 - Funding Information:
We would like to express our gratitude to D. Watanabe and Y. Sugime for their assistance in field sampling and the maintenance of termite colonies. We are also grateful to M. Ohara, for his kind instruction on flow cytometry. This work was supported by a Grant-in-Aid for Scientific Research A (No. 25251041) for TM and by Grant-in-Aid for JSPS Fellows (No. 13J04279) for HS from the Ministry of Education, Culture, Sports, Science and Technology of Japan.
Publisher Copyright:
© 2016, International Union for the Study of Social Insects (IUSSI).
PY - 2016/11/1
Y1 - 2016/11/1
N2 - One of the principal features of eusocial insect societies is the reproductive division of labor, which involves developmental regulation of the reproductive organs. However, although the regulation of caste development is important for establishing social structure in termites, one of the major eusocial insect groups, little is known about reproductive organ development during caste differentiation. Therefore, in this study, we investigated the anatomy and histology of the reproductive organs at various developmental stages during caste differentiation in the dampwood termite Hodotermopsis sjostedti, in which the differentiation of reproductive and non-reproductive castes occurs in late larval instars. We found that the reproductive organs gradually developed during the younger instars in both sexes. However, in females, there were larger variations in ovarian development between individuals in the seventh-instar larvae (i.e., pseudergates), which may reflect variability in their caste fates. By contrast, the testis size did not show such heterogeneity in male pseudergates. Interestingly, presoldiers and soldiers possessed relatively well-developed ovaries or testes containing sperm. When differentiating into the two types of reproductives, i.e., alates and neotenics, the reproductive organs developed rapidly, but the developmental timing of organ growth differed between these as well as between the sexes. Thus, reproductive organ development along the caste differentiation pathways appears to be regulated in a caste- and sex-specific manner.
AB - One of the principal features of eusocial insect societies is the reproductive division of labor, which involves developmental regulation of the reproductive organs. However, although the regulation of caste development is important for establishing social structure in termites, one of the major eusocial insect groups, little is known about reproductive organ development during caste differentiation. Therefore, in this study, we investigated the anatomy and histology of the reproductive organs at various developmental stages during caste differentiation in the dampwood termite Hodotermopsis sjostedti, in which the differentiation of reproductive and non-reproductive castes occurs in late larval instars. We found that the reproductive organs gradually developed during the younger instars in both sexes. However, in females, there were larger variations in ovarian development between individuals in the seventh-instar larvae (i.e., pseudergates), which may reflect variability in their caste fates. By contrast, the testis size did not show such heterogeneity in male pseudergates. Interestingly, presoldiers and soldiers possessed relatively well-developed ovaries or testes containing sperm. When differentiating into the two types of reproductives, i.e., alates and neotenics, the reproductive organs developed rapidly, but the developmental timing of organ growth differed between these as well as between the sexes. Thus, reproductive organ development along the caste differentiation pathways appears to be regulated in a caste- and sex-specific manner.
KW - Blattodea
KW - Caste differentiation
KW - Isoptera
KW - Reproductive division of labor
KW - Termitoidea
UR - http://www.scopus.com/inward/record.url?scp=84978864216&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=84978864216&partnerID=8YFLogxK
U2 - 10.1007/s00040-016-0495-x
DO - 10.1007/s00040-016-0495-x
M3 - Article
AN - SCOPUS:84978864216
VL - 63
SP - 519
EP - 529
JO - Insectes Sociaux
JF - Insectes Sociaux
SN - 0020-1812
IS - 4
ER -