A familiar fruit… or so I thought


  • a common fruit
  • just your run of the mill citrus
  • but how much do we actually know about the lemon itself
  • clearly it’s acidic
  • which is why most people don’t eat them the same way they eat other citruses like oranges or grape fruits
  • you can blame the tooth enamel degrading quality on the high concentration of citric acid in the fruit’s flesh
  • despite that
  • us humans still really like them
  • we like lemons so much that in 2010 14.2 million metric tons of lemons (and limes) were commercially produced
  • quite the jaw dropping figure

Photo by Tower Hill Botanic Garden

  • the lemon tree itself is in the family Rutaceae
  • the citrus family
  • this taxon originated in Asia
  • likely in Pakistan or India
  • curious that it didn’t originate in the Mediterranean
  • as it is so often grown in that region
  • the cultivated lemon did not actually reach the Mediterranean until Roman times
  • the cultivated lemon species, Citrus limon
  • is thought to have arisen as a result of a hybrid between two other Citrus species long ago
  • it could have been the result of some gene mixing within the lineage that includes lime, pomelo, and citron
  • or it may also have been due to a hybridization between a sour orange and a citron

Disentangling evolutionary lineages is fascinating work. There are so many organisms on this planet that we know nothing about, like the multitude of bacteria living on every surface of the human body, the projected 1.5 million species of fungi, and even the origin of the common lemon. Walking through the grocery store and picking up some produce may seem like a mundane activity, but when you grab a lemon, you have in your hand an unsolved evolutionary mystery.


“Lemon — Citrus Limon — Taxonomic Hierarchy of COL-China 2012 — Overview — Encyclopedia of Life.” Encyclopedia of Life. N.p., n.d. Web. 11 Mar. 2016. <http://eol.org/pages/582200/hierarchy_entries/50314493/overview>.