The most recognizable characteristic in the Buceros rhinoceros is the casque above the bill. Buceros rhinoceros species are part of the family Bucerotidae which are omnivorous birds that defend a fixed territory (Kitamura, 2011). In this species we can identify sexual dimorphism. As it can be noticed by pure observation, there is a few differences between sexes. The most significant detectable variations are body and casque length. Adult males show both larger bodies and casques than adult females (Reilly, 1988). There are other features that represent neutral traits for fitness, for example, the casque in males have a special black pigmentation that is not present in female hornbills (Reilly, 1988). This ornamentation has a peculiar …show more content…
For the independent variable I will choose male hornbills with casques smaller and larger than the average. Since manipulation of casques is both unpractical and unethical for this experiment, the trait in individuals required for the experiment must be the result of natural variation. Therefore, a control group is not necessary in this correlational study.
For the experiment I will use the same number of individuals from the two different groups of male hornbills. On the contrary, female hornbills number must be considerably less than the total number of males. According to Kozlowski et. al. (2015) family Bucerotidae species are monogamous. Therefore, by having more females than males, after mating choice we will end up with lone male individuals. In this scenario, the dependent variable is determined by female hornbills’ choosiness.
Male and females individuals have to be left in an environment with similar conditions as their habitat. Before starting the experiment, we have to assure that each female hornbill has one nest cavity. Enough amount of food resources must be provided as well. …show more content…
In this case, we have to consider the internal anatomy of the ornament. In this case, having a larger casque would be described as a variant of the trait decreasing fitness in the individuals. Individuals with larger casques are prone to injury, environmental damage and disease. One of the most common diseases is squamous cell carcinoma which affects the casque (Gamble, 2007). Female individuals would prefer individuals with smaller casques to avoid mates that could not survive the nesting