purpose: to report a case who had optic disc duplication, a rare congenital disorder characterized by two well-defined discs in one eye. case report: a 19 months-old child presented with unilateral epiphora in the right eye since birthday. the right eye was smaller than the left eye and mild ptosis was apparent. nasolacrimal duct probing was performed under general anesthesia. the examination r...

A new experimental study has provided the first definitive evidence for conditional punishment of 'cheats' in a sperm-trading simultaneous hermaphrodite: the sea slug Chelidonura hirundinina. This also provides a rare unequivocal example of conditional reciprocity averting a 'tragedy of the commons' in biology.

In the game of evolutionary fitness, males must maximize the chance that their sperm successfully fertilize oocytes. Speciesspecific strategies include making more, bigger, or faster sperm, or producing seminal fluid that does more than serve as a vehicle for sperm transfer [1]. Importantly, seminal fluid components not only modulate sperm function and promote their competitiveness and long-ter...

Angiosperms are the most diverse group of land plants which provides fruits, food, seed for cultivation and material for hybridization purpose etc. Approximately 90% of all angiosperm species have hermaphrodite (bisexual) flowers and the remaining, onetenth are either monoecious (male and female flowers are separate but grow in same plant) or dioecious (male and female flower grow on different ...

Although the nematode worm Caenorhabditis elegans reproduces primarily as a self-fertilizing hermaphrodite, males are maintained in natural populations at low frequency. In this commentary, I discuss the evolutionary forces that maintain males and the role males might play in this mating system.

Caenorhabditis elegans primarily reproduces as a hermaphrodite. Independent gene conversion events in mutant obligately outcrossing populations of C. elegans [fog-2(lf)] spontaneously repaired the loss-of-function mutation in the fog-2 locus, thereby reestablishing hermaphroditism as the primary means of reproduction for the populations.