After all, we're related!

I am currently tending a very sick palm tree in my garden, which I think has had its roots attacked by hungry beetles. The symptom is a loss of leaves (fans) at an alarming rate and in the past week I have removed over twenty. I had a palm with a similar problem last year, which regrettably ended with the tree being chopped down. There is a small glimmer of hope with the current ailing patient because there is still some new growth from the crown, which might survive and if so, possibly grow and lead to further new shoots. But I know from my previous experience that I'm clutching at straws so as well as removing the poorly fans, I have tidied up the trunk and tried to give the tree a little bit of TLC and dignity during what could be the twilight of its life - after all, we're related! Now before you conclude that I'm off my trolley, let me explain my views on the relationships between me, the rest of mankind and other living species.

Let's start with our own species, homo sapiens. I am the result of a relationship between my two parents (two people). My parents were the results of relationships between two sets of parents (four people). My grandparents were the results of relationships between four sets of parents (eight people). Continuing this historic extrapolation and assuming my ancestral line remains 'pure' (an assumption that I will prove to be invalid later in this blog), let's look at how many people were associated with my current existence, at various points in history. If we go back eight generations, around the time Abraham Lincoln was born, there were 256 people responsible for my birth. Back to the time of Shakespeare and the number becomes 16,384. Twenty generations ago the number has risen to 1,048,576. This doubling every generation means that sixty-four generations ago, around the peak of the Roman empire, the number becomes one million trillion, which is several thousand times the number of people who have ever lived. If I now return to the assumption that my ancestral line is 'pure', clearly that can't be true and my existence, you're existence, everyone's existence is the result of a considerable amount of incest but far enough removed from the main family line so it wouldn't be obvious. This means that most people you come in contact with, including your partner, are probably relatives.

That's all very interesting but what does it have to do with my palm tree? The evidence for evolution is very strong. Indeed, biologists often make a distinction between the FACT of evolution (i.e. all living things are cousins) and the THEORY of what drives it (natural selection versus rival theories). The current estimate for the number of living species is around ten million. To draw all the relationships between the species in the form of a family tree on a manageable-sized piece of paper, is clearly impossible. The best illustration I have seen is the Hillis plot, which transforms the classic plot of a family tree into a more compact circular illustration stripped down drastically to around three thousand species in order to fit into even this huge diagram. In my view, what is more exciting than visual representations of genetic family trees, is what will be possible from processing genetic-relationship information. Over the past fifty years, computer processing power has followed something called Moore's Law. It is an empirical law and can be observed as the doubling of computer processing power in a given volume every eighteen months to two years. In financial terms, this means the cost of processing information is rapidly reducing. Current extrapolations suggest that by 2040 it should be technically possible and affordable to create a massive database of DNA sequences across all the animal and plant species.

So what about my palm tree? Well clearly there is very strong evidence that I have a genetic relationship with it and at some time in the future, probably after I have departed this world, it might be possible to 'plot' our relationship. So why shouldn't I show it the same respect as I should have for my own or any other species on the planet? I'll let you know if it survives.