Extreme offspring ornamentation in American coots is favored by selection within families, not benefits to conspecific brood parasites

Offspring ornamentation typically occurs in taxa with parental care, suggesting that selection arising from social interactions between parents and offspring may underlie signal evolution. American coot babies are among the most ornamented offspring found in nature, sporting vividly orange-red natal plumage, a bright red beak, and other red parts around the face and pate. Previous plumage manipulation experiments showed that ornamented plumage is favored by strong parental choice for chicks with more extreme ornamentation but left unresolved the question as to why parents show the preference. Here we explore natural patterns of variation in coot chick plumage color, both within and between families, to understand the context of parental preference and to determine whose fitness interests are served by the ornamentation. Conspecific brood parasitism is common in coots and brood parasitic chicks could manipulate hosts by tapping into parental choice for ornamented chicks. However, counter to expectation, parasitic chicks were duller (less red) than nonparasitic chicks. This pattern is explained by color variation within families: Chick coloration increases with position in the egg-laying order, but parasitic eggs are usually the first eggs a female lays. Maternal effects influence chick coloration, but coot females do not use this mechanism to benefit the chicks they lay as parasites. However, within families, chick coloration predicts whether chicks become “favorites” when parents begin control over food distribution, implicating a role for the chick ornamentation in the parental life-history strategy, perhaps as a reliable signal of a chick’s size or age. (Includes Supporting information.

Extreme offspring ornamentation in American coots is favored by selection within families, not benefits to conspecific brood parasites

Offspring ornamentation typically occurs in taxa with parental care, suggesting that selection arising from social interactions between parents and offspring may underlie signal evolution. American coot babies are among the most ornamented offspring found in nature, sporting vividly orange-red natal plumage, a bright red beak, and other red parts around the face and pate. Previous plumage manipulation experiments showed that ornamented plumage is favored by strong parental choice for chicks with more extreme ornamentation but left unresolved the question as to why parents show the preference. Here we explore natural patterns of variation in coot chick plumage color, both within and between families, to understand the context of parental preference and to determine whose fitness interests are served by the ornamentation. Conspecific brood parasitism is common in coots and brood parasitic chicks could manipulate hosts by tapping into parental choice for ornamented chicks. However, counter to expectation, parasitic chicks were duller (less red) than nonparasitic chicks. This pattern is explained by color variation within families: Chick coloration increases with position in the egg-laying order, but parasitic eggs are usually the first eggs a female lays. Maternal effects influence chick coloration, but coot females do not use this mechanism to benefit the chicks they lay as parasites. However, within families, chick coloration predicts whether chicks become “favorites” when parents begin control over food distribution, implicating a role for the chick ornamentation in the parental life-history strategy, perhaps as a reliable signal of a chick’s size or age. (Includes Supporting information.

The employability of the physically handicapped in manufacturing organizations in Boston, Massachusetts.

Thesis (M.S.)--Boston Universit

VALUING WILDLIFE MANAGEMENT: A UTAH DEER HERD

Managers of public wildlife resources generally are concerned with enhancing the quality of recreation by increasing wildlife through habitat manipulation. However, current recreation valuation studies have focused upon variables that are inappropriate for use in these management decisions. The economic criterion for these decisions should be the value of a change in the stock of the wildlife population compared to its cost. An estimate of such a value was made for the Oak Creek deer herd in Utah, using a household production function approach in an optimal control framework. The value of an additional deer in the herd was estimated to be approximately $40.00.Resource /Energy Economics and Policy,

Analytical procedure for determining random load acting on a spacecraft due to a primary random load acting on an exterior structure Quarterly report no. 2, 1 Sep. - 30 Nov. 1965

Sound and vibration transmission in OGO SPACECRAFT shroud syste

Case Studies of the Attainment of Insight in Dream Sessions: Replication and Extension

To replicate and extend the Hill, Knox, et al. (2007) case study of a client who attained insight in one session of dream work, the authors examined two additional single-session cases: one in which a client gained insight and another in which a client did not. The observations across all three cases suggest that the two clients who acquired insight had positive attitudes toward dreams; were motivated and involved in session; and were nonresistant, trusting, and affectively present but not overwhelmed. The client who did not gain insight questioned the value of dreams and was resistant, untrusting, andf emotionally overwhelmed. Therapist adherence and competence using the dream model, ability to manage countertransference, and effective use of probes for insight distinguished the therapists whose clients gained insight from the therapist whose client did not

Geological and geothermal investigations for HCMM-derived data

An attempt was made to match HCMM- and U2HCMR-derived temperature data over two test sites of very local size to similar data collected in the field at nearly the same times. Results indicate that HCMM investigations using resolutions cells of 500 m or so are best conducted with areally-extensive sites, rather than point observations. The excellent quality day-VIS imagery is particularly useful for lineament studies, as is the DELTA-T imagery. Attempts to register the ground observed temperatures (even for 0.5 sq mile targets) were unsuccessful due to excessive pixel-to-pixel noise on the HCMM data. Several computer models were explored and related to thermal parameter value changes with observed data. Unless quite complex models, with many parameters which can be observed (perhaps not even measured (perhaps not even measured) only under remote sensing conditions (e.g., roughness, wind shear, etc) are used, the model outputs do not match the observed data. Empirical relationship may be most readily studied