Of the seven glands that deer use to communicate with one another, hunters are probably most familiar with the tarsal gland and its role when deer make a scrape. But have you ever wondered exactly how the tarsal gland works, or how it can stink so bad? The infographic below takes a look at the complex and symbiotic functions that happen to not only make that sucker smell, but also how it allows each individual deer to have its very own calling card year-round.