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Intraspecific variation in testis asymmetry in birds: evidence for naturally occurring compensation

Sara Calhim1, Tim R Birkhead

  • 1Department of Biology, Queen's University, Kingston, Ontario K7L 3N6, Canada. calhims@queensu.ca

Proceedings. Biological Sciences
|March 28, 2009
PubMed

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Dosage Compensation

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Testing a Claim about Mean: Unknown Population SD

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The Ratio of X Chromosome to Autosomes

In most organisms, sex is determined by the ratio of X and Y chromosomes. However, in some organisms, such as Drosophila and C.elegans, sex is determined by the ratio of the number of X chromosomes to the number of sets of autosomes. The Y chromosome in Drosophila is active but does not determine sex. It contains genes responsible for the production of sperms in adult flies.  
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