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Full-Text Articles in Zoology
Analyzing The Longevity Of Sperm Within The Female Japanese Quail By Assessing Sperm Penetration Of The Perivitelline Layer Under Optimal And Suboptimal Conditions., Garret G. Ashabranner, Joey L. Bray
Analyzing The Longevity Of Sperm Within The Female Japanese Quail By Assessing Sperm Penetration Of The Perivitelline Layer Under Optimal And Suboptimal Conditions., Garret G. Ashabranner, Joey L. Bray
Electronic Theses and Dissertations
After mating, birds have the ability to store semen within the female reproductive tract. The sperm storage tubules will store and subsequently release semen to travel up the oviduct. Sperm cells that make the trek up the oviduct have a chance to fertilize the ovum. These sperm cells will bind to the perivitelline layer of the ovum and hydrolyze a hole in the perivitelline layer, where it has the possibility to fertilize the female sex cell. Analyzing the number of penetration points on the perivitelline layer is an effective way to analyze reproductive efficiency. Many environmental factor has its effect …
Glare Reduction By Dark Facial Markings And Bills In Birds, Clara Lebow
Glare Reduction By Dark Facial Markings And Bills In Birds, Clara Lebow
Electronic Theses and Dissertations
Avian facial plumage, bill coloration, and feather microstructure may serve one or more adaptive functions. Several researchers have proposed that dark eyestripes, bills, and facial masks aid in reducing glare, however, there have been relatively few tests of this hypothesis. Dark facial markings have been shown to have an adaptive glare-reduction function in recent field studies of a few species, but this hypothesis has never been tested in a broad multispecies analysis. It is likely that feather microstructure influences feather brightness and has an effect on the efficacy of glare reduction properties of feathers. I examined the link between dark …