Error Catastrophe

The central problem for any theory of the origin of replication is the fact that a replicative apparatus has to function almost perfectly if it is to function at all. If it does not function perfectly, it will give rise to errors in replicating itself, and the errors will accumulate from generation to generation. The accumulation of errors will result in a progressive deterioration of the system until it is totally disorganized. This deterioration of the replicative apparatus is called the "e...

 Correlation != Causation; However, It is Often All We Have

> correlation doesn't mean causation. As a statistician, I guess I should be happy that more people are aware of this. But I also think too many people are taking "correlation != causation" superficially. I mean, almost all of science is based on significant correlational findings, especially when the traditional way to prove causation (i.e. via randomized trial) is unethical (i.e. we can't randomly assign people to be insured vs. uninsured). Along these lines, I often find people who sa...

 Gedankenexperiment

However, the subject need not be an esoteric one for a gedankenexperiment to be fruitful. My own favorite is Galileo’s proof that, contrary to Aristotle’s view, objects of different mass fall in a vacuum with the same acceleration. One might think that a real experiment needs to be conducted to test that hypothesis, but Galileo simply asked us to consider a large and a small stone tied together by a very light string. If Aristotle was right, the large stone should speed up the smaller one...

 Different Cells are Replaced at Different Rates

Different types of cells have different lifespans, e.g.:  we shed our skin cells about every 35 days red blood cells live about 120 days, platelets 6 days and white cells less than a day most of the adult skeleton is replaced about every 10 years the average age of a fat cell seems to be about 10 years a 25-year-old heart replaces about 1% of all its cardiomyocytes (heart muscle cells ) over the course of a year, while a 75-year-old heart replaces about half a percent ...