Though we all know that the survival of the species depends on producing children, up until now we haven't understood how germ cells in the developing embryos decide whether to eventually become the sperm or eggs needed later for adult reproduction. Now we know one way these other cells are talking to germ cells about sex.

Evolutionarily, germ cells are one of the most ancient cell types, needed by every type of animal to reproduce. Their developmental program is very similar, whether we are talking fruit flies or humans. As a result, these findings could eventually help us understand and treat defects in germ cell development that lead to human infertility and disease.

To fail to love is not to exist at all.

To be what no one ever was, To be what everyone has been: Freedom is the mean of those Extremes that fence all effort in

The genius of the Marx Brothers is for parody. They never are themselves. They exist too abundantly to be content with being that - they must go on, by the rapidest of transitions, to being something else. Groucho, in my opinion the bright star among the three, is never anything but the thing he is at the moment pretending to be.

To be what no one ever was,To be what everyone has been:Freedom is the mean of thoseExtremes that fence all effort in.