21 



HORMONAL REGULATION OF PARENTAL 



BEHAVIOR IN BIRDS AND 



INFRAHUMAN MAMMALS 



Daniel S. Lehrman, Ph.D. 



PROFESSOR OF PSYCHOLOGY AND DIRECTOR, INSTITUTE OF ANIMAL 



BEHAVIOR, RUTGERS, THE STATE UNIVERSITY, 



NEWARK, NEW JERSEY 



I.' Introduction 1269 



11.^ Hormones and Parental Behavior in 



Birds 1269 



A. Nest-building 1269 



1. Varieties of nest-building 1269 



2. Correlations hplween nest-building 



and other behavior 1271 



3. Nest-l)uilding and gonadal cycles 1272 



4. Physiologic induction of nest- 



building behavior 1274 



B. Egg-laying 1276 



1. Egg-laying behavior in birds 1276 



2. Hormonal relations in ovulation 



and egg-laying 1277 



3. Stimulation of ovulation 1278 



C. Incubation 1284 



1. Incubation patterns 1284 



2. Hormonal regulation of incuba- 



tion 1284 



3. Interaction between internal and 



external environments in the 

 regulation of incubation behav- 

 ior 1294 



4. Some remarks on the onset of incu- 



bation 1297 



D. Care of the Young 1298 



1. Types of young and methods of 



feeding them 1298 



2. Hormonal induction of parental be- 



havior toward .young 1299 



3. Induction of parental behavior to- 



ward young by external stimuli 1300 



4. Physiologic nonidentity of incuba- 



tion behavior and brood}' care of 



the young ' 1302 



III. Hormones and Parental Behavior in 



Infrahuman Mammals 1304 



A. Nest-building 1305 



1. Nest-building patterns in mam- 



mals 1305 



2. Hormonal basis of nest-building. 1305 



3. Induction of nest-building behav- 



ior by external stimuli 1309 



B. Behavior during Parturition 1310 



1268 



1. Patterns of parturitive behavior. 1310 



2. Physiologic aspects of parturitive 



behavior 1312 



C. Retrieving of the Young 1313 



1. Retrieving behavior 1313 



2. Physiologic regulation of retriev- 



ing behavior 1314 



]). Nursing and Suckling Behavior 1321 



1. Behavior of the nursing mother. . 1321 



2. Milk ejection 1321 



3. Mother-young relationships and 



the regulation of lactation 1325 



4. Nursing behavior and the condi- 



tion of the mammary gland 1330 



IV. General Discussion: the Psychobiol- 

 oGY OF Parental Behavior and the 

 Role of Hormones 1332 



A. Learning and Hormone-induced Pa- 



rental Behavior 1332 



1. General: formulation of the prob- 



lems 1332 



2. Learning and parental behavior . 1332 



B. Hormone Secretion as a "Behavioral" 



Response 1341 



1. Neural conti'ol of hormone secre- 



tion 1341 



2. Hormone secretion as a reflex. . . . 1342 



3. Hormone secretion as a condi- 



tioned response 1343 



4. Parental behavior and reflexly in- 



duced hormone secretion 1343 



C. Mechanisms of Hormonal Action on 



Behavior 1344 



1. Formulation of the problem 1344 



2. Examples of peripheral contribu- 



tions to hormonal effects on be- 

 havior 1345 



3. Central hormonal effects on behav- 



ior 1348 



4. The importance of behavioral anal- 



ysis 1351 



D. Genetic and Evolutionary Aspects of 



Hormone-induced Parental Behav- 

 ior 1352 



