One cluster in particular, dubbed Mr. Arthrobalanus, is notable for being the impetus for Charles Darwin's "Cirripedia project" and obsession with barnacles.

Males are much reduced, one-tenth the size of females, and missing features such as a head and stomach.

[3] Mr. Arthrobalanus was the name given to a colony of C. minutus that Darwin collected off the coast of Chile in 1835.

[2] When Darwin requested other barnacle specimens from research institutions to compare to Mr. Anthrobalanus, he realized the existing work on the subject was insufficient.

[3] Invested deeply in the work, he continued his efforts against the recommendation of his doctors after his health began to fail.