May 13, 2012
Human genome (Photo credit: Wikipedia)
The human genome is about 3.5 billion base pairs, or about 800 MB. But how much of this do humans have in common? Humans and chimpanzees share more than 95% of their genome, which means the difference among humans must be a lot less.
It turns out that a person’s DNA can be compressed to just 4 MB of data, which is in many ways fascinating. Just think about it. What could you fit in 4 MB? A quality photograph of your summer vacation? Your favourite song? Everything that makes you who you are?
February 18, 2012
People tend to perceive things in a logarithmic scale. This includes our perception of light brightness and sound frequency (was it also volume?). Maybe we also perceive time this way. That would make sense because recent events usually affect you more than older ones. Take a look at the following picture:
Picture 1: logarithmic scale
The events spread out so nicely that you can actually relate between too recent and too old. Comparing with the linear timeline below I admit the first picture better reflects my view of these events:
Picture 2: linear scale
Since openoffice does not seem to do timelines, I hacked together a little perl script to make the images. You can get it here.
May 10, 2010
Image via Wikipedia
This is the second time I read “The Blind Watchmaker“. This is an excellent book and in my opinion its a must-read for everyone. It is written in plain English, with no heavy terminology, and besides its brilliant counterarguments against the ones used by creationists, it talks about genetic algorithms as a bonus!
Yesterday night I started reading chapter 3, which presents an excellent argument that I’d like to repeat here. The usual arguments against evolution revolve around complexity and chance. Something along the lines of “Living things are extremely complex, so they couldn’t have been created by chance”. In order to address this argument one must differentiate between types of chance and that’s what this argument does:
Ask yourself two questions:
- Can something that is not a human eye transform into a human eye by chance?
- Can X transform into a human eye by chance, given that X is something very similar to a human eye?
The answer to the first question is by all means, “no”.
The answer to the second one must be a strict “yes”. If you did not answer yes to the second question then you have chosen a wrong X, a very distant from a human eye. Find another one, halfway between your X and the human eye and ask yourself again. Do this for as many times as it takes until the answer is positive. Then you will have a good understanding of the role that chance plays in the process of evolution. Evolution needs just as little luck as that to work!
You can then ask yourself the same question for X itself: Find another X (let’s call it X’) that could have been transformed to an X by chance. Repeat the process many times until you reach an X that is not at all a human eye. Then the process of evolving an eye from no eye at all breaks down into a series of events, that each of them has a relatively high probability of taking place spontaneously.
Even though the concept of very small changes is basic in order to even begin understanding evolution, this is by far the best way to put it, with no technical terms at all but still completely accurate! Dawkins has a rare talent of describing complex things with simple words. I really admire him and I started studying biology because of his books. I only wish there were more people like him among our professors
Side note: Evolution is not a theory. I hear that a lot, usually in the form of a cheap argument. Evolution is a fact as well documented as gravity. Theories like soft inheritance and natural selection attempt to explain the fact of evolution, just like the inverse square law and the general theory of relativity attempt to explain the fact of gravity.