“…. ) and cross-fostering between strains or species (Bolwerk & Swanson, 1984;Crnic, 1976;Deviterne, Kayser, Desor, Divry, Krafft, Royer, & Netter, 1988;Fleisher & Turkewitz, 1981;Mathews & Jamison, 1982;Smotherman, 1983;Villescas, Bell, Wright, & Kifner, 1977;Wiener, Fitzpatrick, Leving, Smotherman, & Levine, 1977). A precise interpretation of these results is compromised by several facts.…”