Aposematic coloration

Terrick T.D., Mumme R.L. and Burghardt G.M. (1995). Aposematic coloration enchances chemosensory recognition of noxious prey in the garter snake Thamnophis radix. Anim Behav 49, 857-866. 

When disturbed or molested, these insects release small droplets of hemo-lymph from the tibio-femoral joints of their legs, and it is now well established that the deterrency exhibited by many species of coccinellids towards potential predators results from the presence of repellent and bitter alkaloids in that fluid [ 12,13]. In ladybirds, this unpalatability is associated with a bright aposematic coloration and a characteristic smell due to 3-alkyl-2-methoxypyrazines [14, 15]. The beetles use these molecules not only to reinforce the visual alerting signal on an olfactory level, but also as aggregation pheromones [16]. 

Aposematically colored, the yellow-bellied sea snake, Pehmis platurus (Hydrophiidae), of the eastern Pacific has venom and is distasteful. It has no known aquatic predators, although remains were found in murray eels and sharks. Predatory fish such as snappers refuse the snake. They reject its meat even when hidden in palatable squid. Predatory fish of the Atlantic ocean, however, ate the sea snake in experiments, and died after 1 of 12 meals (Rubinoff and Kropach, 1970). 

Visual and chemical cues interact in foraging by natricine snakes. Even visual cues alone can elicit prey attack, especially in aquatic foraging (Drummond, 1985). Aposematic color patterns of prey enhance the learning of prey that induces illness. Garter snakes, Thamnophis radix hay deni, were exposed to fish and earthworms presented on black-and-yellow forceps, and then inj ected with lithium chloride (LiCl). Control prey was offered on green forceps. Later, the snakes avoided food from either forceps, but the aversion to prey paired with black-andyellow was stronger (Terrick etal, 1995). 

Young, C. M. and Bingham, B. L., Chemical defense and aposematic coloration in larvae of the ascidian Ecteinascidia turbinata, Mar. Biol., 96, 539, 1987. 

Two phyla of marine invertebrates are mentioned here because they have free-living representatives that move around slowly in pursuit of prey in that respect they are somewhat similar to gastropods. In both of these phyla there are reports of defensive metabolites and aposematic color patterns. Again, the relationships of these animals to other phyla are very remote, and in all probability they evolved within the lineages in question. 

The toxicity of both marine and terrestrial flatworms and its association with aposematic coloration has long been known. Arendt and Walther provide a useful survey of the older literature.129 A few flatworms have been studied with respect to metabolites produced by symbionts. The section about Urochordata discussed flatworms that derive metabolites from food. 

Tullrot, A. and Sundberg, P., The conspicuous nudibranch Polycera quadrilineata aposematic coloration and individual selection, Ann. Behav., 41, 175, 1991. 

Jarvi, T., Sillen-Tullberg, B., and Wiklund, C., Individual versus kin selection for aposematic coloration a reply to Harvey and Paxton, Oikos, 37, 393, 1981. 

Many mite species are aposematically colored but especially in water mites (Hydrachnidia), which are usually avoided by fish (only occasionally found in fish stomachs) and many invertebrate predators, a foul taste (secretion probably from dorsal skin glands) may be correlated with bright colors especially red.103... 

Ladybird beetles produce a wide variety of polyacetate or fatty acid-derived alkaloids, many of which closely resemble the ant venom alkaloids described in the previous section. The original discovery of coccinelline (75) and precoccinelline (100) (Figure 32) in blood of the European ladybird beetle, C. 1-punctata had been motivated in part by these beetles aposematic coloration and their tendency to reflex-bleed when molested. Many ladybird beetle species share these characteristics and correspondingly are chemically protected by alkaloids as well. The carbon skeletons of almost all of these alkaloids are based on simple unbranched chains. The structures, biology, and laboratory syntheses of ladybird beetle alkaloids have been reviewed previously by Daloze et al and by Glisan King and Meinwald. ... 

The larvae of the bug, Caenocoris nerii, feed on ripening seed pods of Nerium oleander plants and also accumulate cardenolides such as oleandrin (28). At night, when aposematic colors are less useful, these insects abandon the conspicuous pods and shelter in twos or threes on the underside of leaves of the plant (Rothschild, 1973). 

Berenbaum, M. R. and E. Miliczky, Mantids and milkweed bugs Efficacy of aposematic coloration against invertebrate predators, Am. Midi. Nat., Ill, 64-68 (1984). 

In addition to the benefits of modification of host physiology and greater ant mutualism, McEvoy (1979) suggests two additional driving forces for evolving group formation in treehoppers increased effectiveness of maternal care and enhancement of aposematic coloration in distasteful species. The latter is probably also the cause of grouping in many of the Hemiptera discussed. 

Lev-Yadun, S. (2003b). Weapon (thorn) automimicry and mimicry of aposematic colorful thorns in plants. Journal of Theoretical Biology, 244,183-188. 

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