1 Legacies and inheritance
There is no doubt that each one of us affects the lives of those who surround us. Many of our interactions with others are very obvious to us and could be described in terms of personal, professional and social relationships. But there are other, often unnoticed, interactions: the mother taking her children to school, the man buying his paper, the youth at the bus stop – all people we see regularly and only notice when they are not there. Younger people are often very worried about what others think of them behind their back, ‘when they are not there’. Older people tend to replace this worry with a concern about how they will be viewed after their death, ‘when they are not there’.
How would you like to be remembered? Write your own epitaph. (How widely do you hope to be remembered? How do you visualize this coming about?)
There will be a few whose lifetime achievements will be immortalized in print, on newsreels and on celluloid but most of us can neither expect nor hope to be remembered in such a way. Rather, we look in particular at our closest friends and family and speculate on how they would carry on without us. If we have descendants, we may have made provision for them. This seems such a natural thing to do that we scarcely give a thought as to why we care for them preferentially.
What is the biological basis for this behaviour?
Our children inherit genes from us, so we could be said to be providing a favourable environment for the continued existence of these (‘our’) genes.
Interestingly, the old adage that ‘maternity is a matter of fact whereas paternity is a matter of opinion’, is reflected in the inheritance laws of some cultures where property and other possessions pass through the maternal line.
Can you think of other ways in which behavioural differences between men and women might reflect certainty, or uncertainty, of paternity?
In many societies and cultures, women's behaviour is carefully monitored and controlled by the family to ensure that no inappropriate sexual activity takes place. Examples are the placing of women in purdah, not allowing them out of the house without a chaperone.
The greater the number of successful matings that an individual achieves, the higher the proportion of their genes left in the population in future generations. Women can only give birth at approximately 9-month intervals, whereas (theoretically) men can father large numbers of children in that time. Consequently, a tendency to promiscuous behaviour is more likely to be found in men than in women.
In most societies, women devote more of their energy to their children's upbringing than do men.
You may have thought of other examples. Our behaviour is not driven solely by our biology. There are many people who are parents for children to whom they are not biologically related. Also, many people arrange for part or all of their material assets to pass to organizations or individuals to whom they are not related. These organizations are often those with a role in health care, such as Sight Savers, MacMillan Nurses and the Marie Curie Foundation, amongst many others.
However, in this course we are more concerned with wider issues of inheritance and these have to do with the ways in which humankind, as a species, is altering its own environment. What effects does this have on individuals, and on populations? Are we leaving a healthy planet for our descendants?