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Corticosterone Levels During Nest Departure Of Juvenile American Kestrels, Julie Heath
Corticosterone Levels During Nest Departure Of Juvenile American Kestrels, Julie Heath
Biology Faculty Publications and Presentations
Many avian behavior patterns, such as breeding, migration and territoriality, are correlated with changes in hormone levels. Elevated levels of corticosterone, an adrenal steroid hormone, are associated with increased foraging and increased activity levels in birds. Young birds about to take their first flight may benefit from elevated plasma corticosterone levels that facilitate locomotor activity and foraging behavior while they are developing flight and hunting skills. I examined the relationship between corticosterone levels and the timing of nest departure in nestling American Kestrels (Falco sparverius). American Kestrels are cavity nesters and typically depart from the nest between 25-30 …
Corticosterone And The Stress Response In Young Western Screech-Owls: Effects Of Captivity, Gender, And Activity Period, Alfred M. Dufty Jr., James R. Belthoff
Corticosterone And The Stress Response In Young Western Screech-Owls: Effects Of Captivity, Gender, And Activity Period, Alfred M. Dufty Jr., James R. Belthoff
Biology Faculty Publications and Presentations
We used a standard handling protocol to examine the stress response of captive young western screech-owls during their active (nighttime) and inactive (daytime) periods and to compare the stress responses of captive and free-living owls. Circulating corticosterone levels were significantly higher during the inactive period than in the active period in this nocturnal species. This suggests that the daily pattern of corticosterone secretion is reversed in nocturnal birds and is correlated with activity period rather than with the light/dark cycle. Young (ca. 4-5 mo old) screech-owls of both sexes showed increases in plasma corticosterone up to 30 min after capture, …
Tribal Relationships In The Gesneriaceae: Evidence From Dna Sequences Of The Chloroplast Gene NdhF, James F. Smith, J. C. Wolfram, K. D. Brown, Cynthia L. Carroll, D. S. Denton
Tribal Relationships In The Gesneriaceae: Evidence From Dna Sequences Of The Chloroplast Gene NdhF, James F. Smith, J. C. Wolfram, K. D. Brown, Cynthia L. Carroll, D. S. Denton
Biology Faculty Publications and Presentations
The tribal relationships of the Gesneriaceae are investigated using ndhF sequences. A full analysis of 70 taxa including 16 species from the Scrophulariaceae, Bigoniaceae, and Acanthaceae as outgroups, resulted in two most-parsimonious trees of 5610 steps each. In all trees the Gesneriaceae were a monophyletic group and Paulownia was the closest single-species outgroup for the analysis. Further analyses eliminated all but the members of the Gesneriaceae and Paulownia in order to better asses relationships within the family. The smaller analysis resulted in a single most-parsimonious tree of 4613 steps. The Klugieae are identified as the sister to the remainder …