2011-05-05
Explanation
This comic takes a scientific look at genetic inheritance across generations to reach an absurd conclusion. It starts with a factual observation: your daughter has half your genes, her daughter has a quarter, her daughter an eighth, and so on, with each generation halving your genetic contribution (1/2^n). The comic then notes that in just 32 generations, your genetic share (1 out of 2^32 = 4.3 billion) will be less than the total number of base pairs in the human genome (about 3 billion), meaning statistically none of your specific DNA may remain.
The comic then draws an intentionally provocative conclusion: since you have no genetic reason to care about what happens to anyone living more than 800 years from now, the rational response would be to put anthrax in time capsules. It further argues that the only way to "incentivize" caring about the distant future would be a systematic inbreeding program, which would keep your genetic share higher across generations -- illustrated with a tangled family tree diagram.
The final panel delivers the punchline: if you know anyone who cares a lot about the long-term future (like someone who says "I recycle because I care about the people of the future"), the logical implication is that they must be an inbreeding enthusiast -- hence the accusation "You pervert!" The votey shows a person saying "I'm just imagining my children's children," with someone replying "I'll bet you are..." adding a suggestive double meaning. The comic is a classic SMBC move of taking a real scientific fact and following its logic to an intentionally uncomfortable and ridiculous extreme.