Male mammals of many species have been observed to lactate under unusual or pathogenic conditions such as extreme stress, castration and exposure to phytoestrogens , or pituitary tumors . Therefore, it is hypothesized that, while most male mammals could easily develop the ability to lactate, there is no selective advantage to male lactation. While male mammals could, in theory, improve offspring's survival rate through the additional nourishment provided by lactation, most have developed other strategies to increase the number of surviving offspring, such as mating with additional partners. Presently, very few species are known where male lactation occurs and it is not well understood what evolutionary factors control the development of this trait. 
GREGORY PETSKO: For thousands of years, long before there was such a thing as a science of chemistry, people were fascinated by plants, because they knew that plants contained substances that could affect people. Coffee will keep you awake. Tobacco contains something that will calm your nerves. Foxglove contains an extract that'll affect your heart. And the whole goal of chemistry in the early part of the 20th century was to understand what these natural products were, to characterize their chemical structures, and figure out how to make them. This was called "natural products chemistry." It was the main branch of chemistry. And in 1929, Vienna, in Austria, was the seat of natural products chemistry. And that's why Percy Julian went there.
NARAYANAN: Oh, yeah. In South India, apart from the treats, there's this particular dish called Deepavali legiyam. It's really supposed to be a medicinal sweet, which is supposed to be a digestive one. And this particular sweet - or you should say (unintelligible) treat it was - is made only in this time of the year, and the ingredients for it are sold by herbal companies in south India. And I wish I could - I really wanted to get a little bit of that coming here, but it's a specialized treat that's only made in Tamil Nadu and the people in Karnataka in Bangalore, there are not too many places selling it.