Proximate Causes of Parental Desertion
{'Code': '08090200', 'Directorate': {'Abbreviation': 'BIO', 'LongName': 'Direct For Biological Sciences'}, 'Division': {'Abbreviation': 'IOS', 'LongName': 'Division Of Integrative Organismal Systems'}}
{'SignBlockName': 'Fred Stollnitz', 'PO_EMAI': None, 'PO_PHON': None}
In many kinds of animals, parental care is essential for the survival of        newborn progeny, yet it is sometimes terminated by the parent long              before the offspring reach full independence.  The ecological causes for        such desertion are diverse, but center on the evolutionary principle of         maximizing reproductive success.  In other words, parents may be able to        raise more young in the long run by truncating investment when the cause        is already lost (for example, during a drought, if the food base                deteriorates dramatically).                                                                                                                                     Recent field studies of birds (egrets and herons) have identified               another condition under which parents appear to abandon already-hatched         young.  When brood size drops from three or four chicks to just one             surviving nestling, parents may forsake it and use the remainder of the         summer breeding season to renest, perhaps thereby producing a larger            brood.  The signal for such a switch in parental behavior is presumably         the number of chicks in the nest.  This idea has been supported by              observational data on two species, but has not been tested                      experimentally.  The present study aims to fill that void with a set of         complementary field experiments, using an extremely common species (the         cattle egret).                                                                                                                                                  In the first experiment, brood size will be artificially reduced from           three chicks to just one, by transferring the newly hatched nestmates to        undersized broods nearby, where they are accepted readily.  Controls            will consist of broods whose young are handled the same amount, but then        returned to their own nest.  Dr. Mock predicts that parents will desert         the singletons more frequently than the control broods.                                                                                                         In order to explore whether this effect decreases as the remaining              amount of breeding season wanes, the first experiment will be run three         times throughout the nesting period, with the prediction that the later         singletons are less likely to be abandoned than those occurring early in        the season.  If so, parents would have to take both number of chicks and        time of season into account.                                                                                                                                    The final experiment involves the behavior of the nestlings themselves.         In this and related species, chicks hatch at different times, and the           slightly older and larger nestlings persecute their younger siblings,           even to the point of killing them.  If becoming a singleton is a                perilous condition (increasing the risk of parental desertion), then            chicks may reduce their rate of fighting siblings when brood size drops         from three to two.  This will be tested by removing the youngest of             three chicks from nests kept under continuous observation and then              replacing it three days later.  If aggression depends on the number of          nestmates, its frequency should dip when only two chicks are present,           but return to baseline levels when the full brood is restored.
{'FirstName': 'Douglas', 'LastName': 'Mock', 'PI_MID_INIT': 'W', 'PI_SUFX_NAME': None, 'PI_FULL_NAME': 'Douglas W Mock', 'EmailAddress': 'dmock@ou.edu', 'NSF_ID': '000254514', 'StartDate': '07/15/1987', 'EndDate': None, 'RoleCode': 'Principal Investigator'}
{'Name': 'University of Oklahoma Norman Campus', 'CityName': 'NORMAN', 'ZipCode': '730193003', 'PhoneNumber': '4053254757', 'StreetAddress': '660 PARRINGTON OVAL RM 301', 'StreetAddress2': None, 'CountryName': 'United States', 'StateName': 'Oklahoma', 'StateCode': 'OK', 'CONGRESSDISTRICT': '04', 'CONGRESS_DISTRICT_ORG': 'OK04', 'ORG_UEI_NUM': 'EVTSTTLCEWS5', 'ORG_LGL_BUS_NAME': 'UNIVERSITY OF OKLAHOMA', 'ORG_PRNT_UEI_NUM': None}
{'Name': None, 'CityName': None, 'StateCode': None, 'ZipCode': None, 'StreetAddress': None, 'CountryCode': None, 'CountryName': None, 'StateName': None, 'CountryFlag': None, 'CONGRESSDISTRICT': None, 'CONGRESS_DISTRICT_PERF': '""'}
{'Code': '1160', 'Text': 'IBN ANIMAL BEHAVIOR'}
{'url': 'https://www.nsf.gov/awardsearch/download?DownloadFileName=1987&All=true', 'xml': '8704466.xml'}