✐ ✐ “Gurskey” — 2006/8/21 — 21:27 — page 251 — #289 ✐ ✐ ✐ ✐ ✐ ✐ 12 Talking Defensively: A Dual Use for the Brachial Gland Exudate of Slow and Pygmy Lorises Lee R. Hagey, Bryan G. Fry, and Helena Fitch-Snyder Introduction On the ventral side of the elbow of the both the slow (Nycticebus bengalensis, N. coucang) and pygmy (N. pygmaeus) lorises, one can perceive a slightly raised, fairly hair-free but barely visible swelling, termed the brachial gland (Figure 12.1). Observers of captive lorises have found that when the animal is disturbed dur- ing capture and handling, the gland secretes about 10 microliters (μl) of a clear, strong-smelling liquid in the form of an apocrine sweat. Typically, male and female lorises assumed a defensive position with head bent downward between uplifted forelegs, like a miniature prize fighter in a clinch, while imparting gland exudate to the head and neck (Fitch-Snyder, pers. obs.). The lorises frequently AQ1 licked their own brachial gland regions, and also wiped these glands against their heads. The gland is active in lorises as young as 6 weeks (Fitch-Snyder, unpubl. data). Early observers of the loris concluded that the gland contains a form of toxin, basing this conclusion primarily on reports from individuals on the receiving end of painful, slow-healing bites. Lorises have a specialized needle-like, oral tooth comb used for grooming, and the close association with this comb and the licking of the gland made it a natural assumption to visualize the comb as a device for injecting brachial gland derived toxic secretions. Although the design of advanced venom delivery architecture (injecting poison hypodermically through a sharp-pointed tube) has evolved numerous times in vertebrates (i.e., gila monsters, stingrays, stonefish, snakes), offensive and defensive toxins are seldom found in mammals. The platypus and water shrew are the mammals most well documented in the use of this strategy. Thus, the loris would be a singular example of a primate that uses a toxin, has a specialized device for injecting it, and that loads its “sting” in a secondary manner by retrieving the toxin from a part of the body not associ- ated with the toothcomb. Specialized teeth on the lower jaw of the loris have been shown to be effective in conducting liquid upward (Alterman, 1995). 251