Albert, Norwich asked:
How is your lifespan determined?
There are a number of factors here, one of which is the size of the animal. Mice life, on average, about 6 weeks in the wild, though they can live up to 2 and a half years in ideal conditions. A human, however, can live well in excess of 80 years. There must, therefore, be a genetic element to this, as mice and men are separated by a small difference in genetics. Other factors such as lifestyle decisions affect your lifespan, but longevity does seem to run in families. If your family has large numbers of supercentenarians (people who are over 110) then you have a higher chance of living a long life. There's increasing evidence that your cellular metabolism also affects how you age.