Leptopanchax opalescens is a critically endangered small annual fish. Reproductive traits of this species were studied to improve our understanding the strategies that facilitate occupation temporary wetlands. We compiled egg diameter and maximum total length data from 136 neotropical killifishes (Rivulidae) establish comparisons between with different life histories. tested hypothesis have sma...

Embryonic diapause (ED) is a temporary arrest of embryo development and is characterized by delayed implantation in the uterus. ED occurs in blastocysts of less than 2% of mammalian species, including the mouse (Mus musculus). If ED were an evolutionarily conserved phenomenon, then it should be inducible in blastocysts of normally non-diapausing mammals, such as domestic species. To prove this ...

The mink corpus luteum (CL) involutes after ovulation and remains dormant, synthesizing low amounts of progesterone until reactivated to terminate embryonic diapause. We examined the mitotic and steroid synthetic capacity of luteal cells from the diapause and postimplantation phases of mink gestation. Cells from diapause divided in vitro, reaching confluence in 7-8 days. Three phenotypes were d...

Mutations in daf-2 and age-1 cause a dramatic increase in longevity as well as developmental arrest at the dauer diapause stage in Caenorhabditis elegans. daf-2 and age-1 encode components of an insulin-like signaling pathway. Both daf-2 and age-1 act at a similar point in the genetic epistasis pathway for dauer arrest and longevity and regulate the activity of the daf-16 gene. Mutations in daf...

Diapause is an actively induced dormancy that has evolved in Metazoa to resist environmental stresses. In temperate regions, many diapausing insects overwinter at low temperatures by blocking embryonic, larval or adult development. Despite its Afro-tropical origin, Drosophila melanogaster migrated to temperate regions of Asia and Europe where females overwinter as adults by arresting gonadal de...

Human pluripotent stem cells (hPSCs; both embryonic and induced pluripotent) rapidly proliferate in adherent culture to maintain their undifferentiated state. However, for mammals exhibiting delayed gestation (diapause), mucin-coated embryos can remain dormant for days or months in utero, with their constituent PSCs remaining pluripotent under these conditions. Here we report cellular stasis fo...

The white spotted tussock moth, Orgyia thyellina, is a typical insect that exhibits seasonal polyphenisms in morphological, physiological, and behavioral traits, including a life-history tradeoff known as oogenesis-flight syndrome. However, the developmental processes and molecular mechanisms that mediate developmental plasticity, including life-history tradeoff, remain largely unknown. To anal...

The molecular pathways that link nutritional cues to developmental programs are poorly understood. Caenorhabditis elegans hatchlings arrest in a dormant state termed "L1 diapause" until food is supplied. However, little is known about what signal transduction pathways mediate nutritional status to control arrest and initiation of postembryonic development. We report that C. elegans embryonic ge...

The role of photoperiod in the induction of diapause in eggs laid by field-collected adult Aedes sollicitans mosquitoes was examined at different temperatures. Short-day photoperiods induced a much higher incidence of diapause at 15 degrees than at 22 degrees C, whether eggs were 0, 1, 2, 3, 4 or 5 days old postoviposition on exposure. A 6-week exposure to a 6:18 to 10:14 (L:D) photoperiod at 1...