3 upvotes, 1 direct replies (showing 1)
View submission: xkcd 1338: Land Mammals
welp...
Comment by [deleted] at 06/03/2014 at 04:24 UTC
6 upvotes, 2 direct replies
Because I was bored...
From http://en.wikipedia.org/wiki/List_of_Columbiformes_by_population[1], counting species that number 1mil+, we get an estimated total population of somewhere in the 500-600mil range. http://www.ask.com/question/how-many-pigeons-are-there-in-the-world[2] gives an estimate of 400mil, so let's go with 500mil. Wikipedia gives the rock pigeon weight as around 11oz. Taking them as the average pigeon, this gives an estimated pigeon biomass of about 140000 metric tons. So pigeons don't rate even a single box on the chart (you'd need about 7-8x the number of pigeons to get one box).
1: http://en.wikipedia.org/wiki/List_of_Columbiformes_by_population
2: http://www.ask.com/question/how-many-pigeons-are-there-in-the-world
Getting population numbers for rats is more difficult. I found http://answers.yahoo.com/question/index?qid=20090915125805AAJmXEN[3], which estimates 1 rat per 36 people in NYC in 1949, and http://www.mphonline.org/most-rat-infested-cities-in-the-western-world/[4] which says NYC is most infested (but sadly does not give numbers). If we go with that, and Wikipedia's figure of about 200g per black rat, that gives us a global estimate of about 40 metric tons, which also doesn't rate even a single box.
3: http://answers.yahoo.com/question/index?qid=20090915125805AAJmXEN
4: http://www.mphonline.org/most-rat-infested-cities-in-the-western-world/
Bonus:
Various sources put the number of cats at up to a billion. This is consistent with the US population and number of cat pets. The actual number could be higher if the rest of the world has a higher per-capita feral cat population. Assuming a billion cats and 10lbs per cat, this gives us a total cat biomass of 4.5 million tons - this definitely warrants at least four boxes, and I'm surprised cats aren't featured on the comic!