Body size - realized fecundity relationship of whitemarked tussock moth
Insect body size and fecundity are frequently reported to be correlated (e.g., Miller 1957; Dempster 1971; Beckwith 1976; Hough and Pimental 1978; Gilbert 1984; Carroll and Quiring 1993; Honek 1993; Spurgeon et al. 1995; Tammaru et al. 1996, 2002; Nylin and Gotthard 1998). The main body of evidence for this relationship stems from laboratory experiments where potential fecundity (or total egg production) is most often measured (Tammaru et al. 1996); very little evidence is available from field studies (Sopow and Quiring 1998). Realized fecundity (or total eggs laid) is affected by many extrinsic factors (e.g., Leather 1988; Carroll and Quiring 1993; Tammaru et al. 1996), suggesting that fecundity measures derived from laboratory experimentation may not be useful in nature where abiotic conditions may be highly variable (Carroll and Quiring 1993; Nylin and Gotthard 1998; Sopow and Quiring 1998).