2014-11-01
Explanation
The Joke
A narrator explains the biological concept of "handicapping" -- where animals do something very difficult that does not improve survival in order to honestly signal their genetic quality to potential mates. The classic example given is the peacock's fancy tail. Then, in a flashback labeled "Earlier...", a woman says, "I can't believe you're dating a philosophy major," implying that choosing to date a philosophy major is itself a form of handicapping -- a costly signal of quality.
The Humor
The comic draws a parallel between the peacock's extravagant tail and dating a philosophy major. In evolutionary biology, the handicap principle (proposed by Amotz Zahavi) suggests that costly, seemingly pointless displays serve as honest signals of fitness -- only a truly strong organism can afford to waste resources on an enormous tail. The joke is that dating a philosophy major is similarly a costly signal: it provides no practical benefit (philosophy majors being stereotypically unemployable), and it is difficult (presumably involving many long, abstract conversations). Therefore, only someone of very high "quality" could afford to take on such a burden. It is simultaneously a joke about evolutionary biology and a dig at philosophy as an impractical field of study.
References
The handicap principle was proposed by Israeli biologist Amotz Zahavi in 1975. It explains why costly traits like the peacock's tail persist despite being survival disadvantages -- they serve as honest signals of genetic fitness because only healthy individuals can afford the cost. The joke about philosophy majors plays on the common stereotype that philosophy degrees have poor employment prospects.