Fig. 1. Log-log relationship of field metabolic rate to body mass in 229 species of terrestrial vertebrates. The line is the least-squares regression for all the data. Mammal species are represented by filled circles, birds are shown with shaded circles and reptiles are indicated by shaded, inverted triangles. Sources of the data are given in full in Nagy (1987, 1994), Nagy and Obst (1991) and Nagy et al. (1999).

In summary: birds (Adams et al., 1987; Ambrose et al., 1996; Balance, 1995; Birt-Friesen et al., 1989; Brown et al., 1996; Bryant, 1997; Bryant and Westerterp, 1980; Bryant and Tatner, 1988; Bryant et al., 1984, 1985; Carlson et al., 1993; Castro et al., 1992; Chappell et al., 1993; Costa and Prince, 1987; Cuervo et al., 1996; Culik and Wilson, 1992; Dykstra and Karasov, 1993; Ellis et al., 1983; Fiala and Congdon, 1983; Flint and Nagy, 1984; Gabrielsen et al., 1987; Gales and Green, 1990; Gales et al., 1993; Gettinger et al., 1985; Goldstein and Nagy, 1985; Hails, 1979; Hails and Bryant, 1979; Hodum et al., 1998; Jonsson et al., 1996; Kam et al., 1987; Klaassen et al., 1992; Masman et al., 1988, 1989; Mehlum et al., 1993; Mock, 1991; Moreno, 1989; Moreno et al., 1988, 1991, 1995; Moreno and Sanz, 1996; Nagy et al., 1984, 1999; Nagy and Obst, 1992; Obst and Nagy, 1992; Obst et al., 1987, 1995; Pennycuick et al., 1990; Pettit et al., 1988; Piersma and Morrison. 1994; Powers and Conley, 1994; Powers and Nagy, 1988; Reyer and Westerterp, 1985; Ricklefs and Williams, 1984; Ricklefs et al., 1986; Riedstra et al., 1988; Roby and Ricklefs, 1986; Tatner, 1990; Tatner and Bryant, 1993, Tinbergen and Dietz, 1994; Utter and LeFebvre, 1973; Uttley et al., 1994; Vehrencamp et al., 1989; Ward, 1996; Weathers and Paton, 1997; Weathers et al., 1996; Weathers and Nagy, 1980; Weathers and Stiles, 1989; Weathers and Sullivan, 1993; Westerterp and Bryant, 1984; Williams, 1988a,b, 1993; Williams and Nagy, 1984, 1985; Williams et al., 1993, 1995; Williams and Du Plessis, 1996; Williams and Dwinnel, 1990); mammals (Arnould et al., 1996; Bell et al., 1986; Berteaux et al., 1996, Bradshaw et al., 1994; Chevalier 1989; Costa and Gentry, 1986; Costa and Trillmich, 1988; Costa et al., 1985, 1989a, 1989b, 1990; Covell et al., 1996; Degen et al., 1986, 1991, 1992, 1997, 1998; Ellis et al., 1995; Foley et al., 1990; Geffen et al., 1992; Gettinger, 1984; Girard, 1998; Gorman et al., 1998; Green and Rowerowe, 1987; Green et al., 1989, 1991, 1992; Grenot et al., 1984; Hayes, 1989a,b; Helversen and Reyer, 1984; Holleman et al., 1982; Karasov, 1981; Kenagy et al., 1989; Krockenberger et al., 1998; Kunz et al., 1998; Kurta et al., 1987, 1989, 1990; Meerlo et al., 1997; Munger and Karasov, 1994; Monks and Green, 1995; Mullen, 1971a,b; Mullen and Chew, 1973; Mutze et al., 1991; Nagy et al., 1978, 1991; Nagy and Gruchacz, 1994; Nagy and Knight, 1994; Nagy and Martin, 1985; Nagy and Milton, 1979; Nagy and Montgomery, 1980; Nagy and Suckling, 1985; Nagy et al., 1990a,b, 1995; Peterson et al., 1976; Racey and Speakman, 1987; Randolph, 1980; Reilly and Fedak, 1991; Salsbury and Armitage, 1994; Seymour et al., 1998; Shoemaker et al., 1976; Smith et al., 1982; Speakman, 1997; Stephenson et al., 1994; Wallis and Green, 1992; Wallis et al., 1997; Williams et al., 1997); reptiles (Anderson and Karasov, 1981, 1988; Beaupre, 1996; Benabib and Congdon, 1992; Bennett and Nagy, 1977; Bickler and Nagy, 1980; Bradshaw et al., 1987; Brown and Perez-Mellado, 1994, Brown et al., 1992, Brown, 1999; Christian and Green, 1994; Christian et al., 1995, 1996a,b; Congdon and Tinkle 1982; Congdon et al., 1979; Dryden et al., 1990, 1992; Green et al., 1986, 1991a,b, 1997; Grenot et al., 1995; Henen, 1997; Karasov and Anderson, 1998; Kingsbury, 1995; Marler et al., 1995; Mautz and Nagy, 1987; Merker and Nagy, 1984; Nagy, 1982; Nagy and Bradshaw, 1995; Nagy and Degen, 1988; Nagy and Knight, 1989; Nagy and Medica, 1986; Nagy and Shoemaker, 1975, 1984; Nagy et al., 1984, 1991, 1993; Peterson, 1996; Peterson et al., 1998; Robinson, 1990; Secor and Nagy, 1994; Thompson et al., 1997; Van Marken Lichtenbelt et al., 1993; Vernet et al., 1988, 1995; Znari and Nagy, 1997).