Trail odors

Rats learn from group members about new food sources, and clans may develop food traditions. How does one rat transmit to another this information about food. This type of intraspecific communication employs both body and foreign odors. Bennet Galef and coworkers (1985) showed that observer rats who encounter demonstrator rats with food odor on their heads will prefer that food over another when given a choice later. It is important that the food odor is on the head portion of a live rat if it is applied to the rear end of a rat or to the head of a dead rat, it has no effect (Galef and Stein, 1985). 

House mice, M. musculus, also respond to carbon disulfide. Two drops of solutions of different concentrations were added to food pellets. The mice entered an enclosure with treated bait more often, spent more time there, and consumed more food than in an enclosure with water-treated pellets. As in rats, females responded more than males. Higher concentrations of carbon disulfide attracted the mice more than lower ones. Carbon disulfide was more effective than butanol, suggesting that it is a specific cue (Bean etal., 1988). 

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Garter snakes can be trained to correctly follow trails of earthworm extract in a four-choice maze. Snakes are most accurate following high concentration trails and increase their tongue-flick rate as a function of earthworm extract concentration (Kubie and Halpem, 1978). Vomeronasal nerve lesions, but not olfactory nerve lesions, result in a loss of accurate trail following and a loss of increased tongue-flicking in response to trail odor concentrations (Kubie and Halpem, 1979). 

Price, P. W. (1970) Trail odors recognition by insects parasitic on cocoons. Science, 170, 546-7. 

Six juvenile garter snakes (Thamnophis sirtalis and Thamnophis radix), three of each sex, were used in this study. The snakes were housed individually in ventilated plastic containers. During earthworm extract trailing and the foraging task snakes were fed earthworms only in the maze. During airborne delivery of odors and open field exploration snakes were fed earthworms once a week, just before a two day weekend during which they were not tested. Water was available ad libitum. 

The present study has examined tongue usage in four experimental situations prey extract trailing, foraging, open-field exploration and during delivery of airborne odors. The same animals were tested in each experimental situation to facilitate comparisons of tongue-flick parameters in the different tasks. 

The two blind mice experiment of Alyan and Jander (1994) used the pup-retrieving behavior of female house mice to determine the visual cues they use for orientation in an arena of Im diameter. A strain of blind mice did not orient as well as intact mice. In different experiments, neither sighted nor blind mice appeared to use olfactory cues such as scent trails in sand, or the odors of wooden blocks in the arena, to find their nest after their arena had been rotated by 90 degrees. Such rotation misled them on their way home, despite landmarks in their arena with odor that should have been familiar to them. We know little on the role of olfactory cues in such short-range orientation. 

Chapter 6 discussed signaling pheromones that allow discrimination, recognition, and broadcasting dominance and territorial status. This chapter explores the role of pheromones and other odors in reproduction, alarm, trail following, and in connection with food. Some evolutionary considerations conclude the discussion of signaling pheromones. 

Female snakes leave odor trails as they move through vegetation. Their body odor adheres to the anterolateral surfaces of vertical objects. Males then are able to determine the direction of a female s path. The plains garter snake, Thamnophis radix, extracts information in this way (Ford and Low, 1984). 

Neonate garter snakes, Thamnophis sirtalis, and brown snakes distinguish conspecific from heterospecific odors (Burghardt 1977, 1983). Newborn timber rattlesnakes, Crotalus horridus, are able to follow conspecific odor trails (Brown and MacLean, 1983). Neonate water snakes are attracted to conspecific odor (Scudder et ah, 1980) and neonate prairie rattlesnakes, Crotalus viridis, to lipoids from the epidermis of adult conspecifics (Graves etal., 1987). 

Odor trails lead from the birthing rookeries of pregnant snakes to their ancestral winter dens. These trails probably help the neonates to find shelter (Graves et al., 1987). Socially naive neonate prairie rattlesnakes were tested for odor... 

Two phenomena of reptilian prey searching are well investigated responses of various snakes to the odors of invertebrates, and rattlesnakes trailing of envenomated small mammals. 

Hatchling pine snzkes,Pituophismdanoleucus, ofthe Pine Barrens in New Jersey prefer mouse odor in a Y-maze more if they have been incubated at a higher temperature (33 °C versus 28 °C). Furthermore, experience plays a role in this species, too. Snakes that had eaten a mouse detect and follow a mouse odor trail, while naive snakes show no such response (Burger, 1991). 

Blind snakes find their prey by using the prey s pheromones. The wormlike Texas blind snake, Leptotyphlops dulcis, of the southwestern United States leads a subterranean life and feeds on termites and ant brood. It finds ants by following their pheromone trails (Gehlbach etal, 1968). Other blind snakes such as the American blindsnake, Typhlops pusillus (Gehlbach et al, 1971), and the Australian blindsnake, Ramphotyphlops nigrescens (Webb and Shine, 1992), also follow odor trails of ants, their prey. Texas blind snakes are attracted to the simple alkaloid skatole (methyl indole Fig. 12.4), an amine with an unpleasant odor from the ant Neivamyrmex sp. (Watkins etal, 1969). 

Thirty years on the odor trail from the First to the Tenthinternational Symposium on Chemical Signals in Vertebrates. In Chemical Signals in Vertebrates, vol. 10, ed. R. T. Mason, M. P. LeMaster, D. Muller-Schwarze, pp. 1-6. New York Springer. 

While it has been known for centuries that bloodhounds, for example, can tell individuals apart even by the attenuated odors from their bodies left on a trail, the first scientific work which hinted at the existence of substantial biochemical distinctiveness in human specimens was the discovery of blood groups by Landsteinei about 1900. 

Where trees infested with tent caterpillars are available, they can be studied as they follow odor trails along branches or twigs of trees. Their odor trails along branches can be experimentally manipulated by interrupting, reversing, or covering them with other odors (Travis 2003). Look for apple trees or other members of the Rosaceae family in spring. 

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