Doves response

Figure 5.5. A. Schematic illustration of the E. coli RNA polymerase showing the domain structure of the a subunit. The cx-NTD domain is responsible for assembly of RNAP while the a-CTD domain binds DNA and is a target for transcriptional activators. B. The two-hybrid system is based on the interaction of proteins that are fused to the X repressor and NTD domain of the a subunit of RNAP. In the example shown, Gal4 interacts with Gall IP to recruit RNAP to the promoter and activate transcription of the lacZ reporter gene. Figure adapted from Dove and Hochschild (1998).

Without the benefit of understanding the complexities of the immune system, particularly at the molecular level, much progress was made over the years in taking advantage of certain antigens and a qualitative or desenptive understanding of the immune response. This was the early dove logmen l of vaccines and antitoxins. 

As has been mentioned, in pigeons and doves the young are fed by a milk-like fluid regurgitated from the crop. This milk is formed by a sloughing of cells from the wall of the crop sac, a process which is stimulated by prolactin [96,97]. The hormone stimulates both an increase in proliferation of the cells which contribute to the milk and a change in the proteins and lipids contained within the cells [97,98], and these two types of response appear to be controlled independently [99]. The effect is a direct one, and prolactin can produce local effects when injected in the immediate vicinity of one side of the crop. 

CIC (Z)-3-hexenal and 2-(2-methylpropyl)thiazole form the fresh, green, vegetable topnote and a trace of damascenone is responsible for the floral background. On cooking, the fresh note from (Z)-3-hexenal is covered by the sweet sulphurous note of dimethyl sulfide. In canned tomatoes, the sulphurous note is supported by the spicy, dove-like aroma of 4-vinyl guaiacol and eugenol. 

The oil contains the phenol-eugenol with small quantities of cineol, laevo-phellandrene, caryophyllene, eugenol-methyl ether, and palmitic acid. The eugenol is, of course, responsible for the dove-like odour of the oil, and the other bodies, together with one or more as yet unknown constituents, modify the characteristic odour of the oil. A certain amount of resin, due no doubt to the unstable nature of some of the constituents, is usually present. The actual amount of eugenol in the oil is approximately estimated by absorption with 5 per cent, caustic soda solution, as in the case of oil of cloves. 

Figure 1. The responses of mourning doves (6) to mixtures of 30 mottled (M) seeds and 15 grey (G) seeds. Drawn from data presented hy Cook et at. ( 23).

Aldehydes and ketones often have characteristic and recognizable odors. For example, 2-heptanone is a liquid with a dove-like odor that accounts for the odors of many fruits and dairy products. Some aldehydes and ketones find use as flavoring agents. For example, vanillin, the compound responsible for vanilla flavor, is an aldehyde. Alpha-demascone and 2-octanone are ketones responsible for berry and mushroom flavors, respectively. Butanedione, shown in the margin, is a yellow liquid with a cheese-like smell that gives butter its flavor. 

Behavioural strategies are associated with profound differences from the level of gene expression through the metabolome to the neuroendocrine, immune and other systems (MacKenzie et al., 2009). These differences are not only at the level of the neuroedocrine and immune systems but may be mediated through perception since hawks are inherently less responsive to environmental changes. In both hawks and doves an event can be more stressful if it is unpredictable. 

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