Vibration and animal communication: A review

American Zoologist, Nov 2001 by Hill, Peggy S M

The African tok-tok beetle (Psammodes striatus) taps its abdomen on the substrate and is able to locate females with approximately 10% of the energy that would be required to do a walking search (Lighton, 1987). Stone fly (Order Plecoptera) males and females tap the substrate with their abdomens in alternating patterns (Rupprecht, 1968) that are distinct enough to yield data useful in phylogenetic studies (Szczytko and Stewart, 1979; Zeigler and Stewart, 1985). Males of the tenebrionid, Eupsophulus castaneus, tap with their abdomens in aggregations around UV lights in the southwestern United States. Since females do not tap, and since the sex ratio at the sites is 3: 1, it is suggested that the substrate tapping might be a form of sexual advertisement in a lek system, or that it could play a role in male-male spacing (Slobodchikoff and Spangler, 1979). The East African desert tenebrionid beetle (Phrynocolus somalicus) taps its abdomen against a substrate of eroding sandstone (Zachariassen, 1977), and both males and females produce similar sounds (Kristensen and Zachariassen, 1980). Since there appears to be no mechanism to discriminate sex of the tapper from components of the signal alone, the vibration serves to attract members of the same species, and identification of sex takes place at closer quarters (Kristensen and Zachariassen, 1980). Male tenebrionids, Eusattus convexus, from Texas rap their abdomens on a substrate after physical contact with females, and often rap on the head or abdomen of the female (Pearson and Allen, 1996). Three species of tentyriid beetles (Eusattus spp.) tap the substrate with their abdomens. Only males tap, and tap rate tends to increase in the presence of females (Tschinkel and Doyen, 1976).

Short-winged female meadow katydids (Conocephalus nigropleurum) discriminate among tremulation signals of males to choose a larger male, even in the absence of a signalling male (DeLuca and Morris, 1998). Female wandering spiders (Cupien-- nius getazi) use vibration signals for mate recognition but not female choice (Schmitt et al., 1994), but female wolf spiders (Hygrolycosa rubrofasciata) actively choose males based on their drumming rate (Kotiaho et al., 1996). Drumming activity does predict male survival, and so females may use drumming rate as an indicator of male fitness rather than as an index of male body mass (Kotiaho et al., 1996). Drumming has both acoustic and vibratory components in wolf spiders, and the relative importance of either of these has not yet been determined (Parri et al., 1997).

In addition to communication during courtship and reproduction, vibrations can transfer information among social groups, including sibling groups. Nymphs of the treehopper, Umbonia crassicornis, display a sibling-group alarm signalling when one is attacked by a predator. Their mother responds to the plant-borne vibration to defend her offspring, but she only responds to the group signal (Cocroft, 1996). The female in turn uses vibration to signal to her offspring at a low rate throughout the day, and these signals appear to play a major role in maternal care. By signalling through the plant tissue, mother and offspring can communicate outside the perception range of their most common predators (Cocroft, 1999).