NO EVIDENCE FOR A Y-CHROMOSOMAL EFFECT ON ALTERNATIVE BEHAVIORAL STRATEGIES IN MICE

This study takes the first step toward testing a Y chromosomal effect on both aggression and thermoregulatory nest-building behavior in mous e lines either bidirectionally selected for short (SAL) and long (LAL) attack latency or high (HIGH) and low (LOW) nest-building behavior. U sing reciprocal crosses between SAL and LAL, and between HIGH and LOW, we found no indications for Y chromosomal effects on thermoregulatory nest-building behavior. As for aggression, we confirmed earlier studi es on SAL and LAL, i.e., the origin of the Y chromosome influences att ack latency, i.e., aggression. However, we did not find indications fo r a Y chromosomal effect on aggression in the HIGH and LOW lines. Sinc e aggression and nest-building behavior have been shown to be characte ristic parameters of two fundamentally different behavioral strategies , the present data underline the improbability of Y chromosomal genes underlying the genetic architecture of alternative behavioral strategi es.