One Early in the 1960s, Rachel Carson published a book with a perfect title for the point she was making. If we don’t watch out we may be in store for a Silent Spring, a time in which the precious sounds of the natural world no longer exist because of the poison we are spreading to kill the weeds and insects that bother us and our agricultural endeavours. I found this statement on the web, “What was it that allowed Rachel Carson to capture the public imagination and to forge America’s environmental consciousness?” I don’t know the answer to this question but note that to the day of the 50th anniversary of the publication of Carson’s book on September 27 1962, an article reviewing the scientific literature in this area appeared in the influential magazine Science with the title, Life in a Contaminated World, ending with the statement, “Rachel Carson was right: Chemical contaminants play an important role in our health and the health of the environment.” The article, which I recommend, (Science, 28 September 2012, volume 337, pages 1614-1615) is wide ranging including the increasing understanding that exposure of future parents to our chemically contaminated world has an effect on the biochemical makeup of their progeny. We pass on the consequences of the contaminants to which we are exposed, to our children even if they are not exposed.
Two Korean professors from Incheon and Seoul, in collaboration with a scientist from the National Institute of Korean History in Gwacheon aware of the fact that in many species, including humans, males live shorter lives than do females, decided to take advantage of historical information about the detailed lives, including birth and death dates of Royal Court eunuchs who lived between the mid-16th century and the mid-19th century. Their idea was that eunuchs lost their capacity to produce testosterone, the male sex hormone and this hormone might be responsible for the earlier deaths of the male of so many species, including our own. As reported in the journal Current Biology (Volume 22, Issue 18, R792-R793, 25 September 2012) the Korean investigators found that the castrated men lived on average 14 to 19 years longer than testosterone driven men of the same time period and lifestyle with an additional astonishing finding that more than 3% of the castrated men lived to be more than 100 years old. The usual statistic for centenarians is less than one in about four thousand. Although one hardly regrets it, could it be unhealthy to be testosterone pumped up and lusting after the ladies? Gentlemen, would you give it up for a longer life?
Three The phenomenon of sleep, which has been of interest to this series (http://blogs.poly.edu/markgreen/2010/11/04/science-from-away-why-sleep/) is still pretty much of a mystery to science. The Avian Sleep Group of the Max Planck Institute for Ornithology in Seewiesen, Germany found something new about Sandpipers, which breed in the high Arctic where the sun never sets during the mating period. A successful male has to display his fitness to the female Sandpiper by fighting and outshining his competitive males with courtship displays. The hypothesis was that even though there were female birds in view and ready to mate 24 hours a day, sleep would be required for the male bird to be on his toes to do the best job or, as the scientists put it, “experience enhanced neurobehavioral performance.” Getting some rest would be more important than having more hours of access to the female birds. However, the scientists discovered that birds that slept less and could therefore take advantage of the 24 hours of sunshine to find females, mated most and sired the most offspring. Even on less sleep, these male birds were more attractive to the female birds than their well rested competitors. If genes are involved, one would expect that the birds which got more sleep and therefore sired fewer offspring of their sleepy type, would diminish in numbers. Yet these longer sleeping birds seem to be equally competitive over the long run. Their numbers don’t diminish. It’s not clear why. The German scientists hope that studying these birds may reveal more about sleep in human beings and the choices we make between sleeping and mating.
