sex bias, sex ratio, babblers, bird, breeding
This research project involved analysis of the significance level of biases in chestnut-crowned babblers by definition of provisioning rate and analysis of the sex ratio of broods over several years. The aim was to test significance of difference between brood ratios and provisioning/helper rates. To determine sex, blood samples from these 2007 babblers were previously separated and purified, then run through PCR, implementing several molecular techniques. Finally, the sex chromosomes were amplified to determine sex through gel electrophoresis. Once this was determined, sex ratios were compared to provisioning data collected with PIT tags and look for a correlation between them. The PIT (passive integrated transponder) tags record how often that bird travels to the nest. After gathering this information, we will be able to run statistical analysis (mixed model analysis using individual and group as random factors) to answer our question. An ANOVA mixed test was run on the calculated brood ratio and helper individuals to determine significance. For the 2007 samples, a p value of 0.2385 showed a lack of significance; however, further analysis of 2008-2015 will be completed for a comprehensive approach to this project.
Brust, Katie, "Measuring sex biases; Does sex ratio of a brood determine provisioning rate in a cooperatively breeding bird" (2021). IdeaFest. 288.