Under sedation after being wounded in the posterior, McKay incoherently babbles about "All the Pretty Horses". "All the Pretty Horses" is a novel where the protagonist too gets wounded in a similar location on his body.
Jason Momoa performed some of the Haka, an intimidating Maori war dance traditionally used on the battlefield, right before he fights the head Wraith. He also does this in a Season 1 episode of Game of Thrones (2011).
The title refers to Ronon's home planet, where most of the action takes place.