Dietary And Environmental Factors Affecting Sexual Selection

Dietary and environmental factors play a key role in many aspects of life, whether human or animal. This paper will discuss the many dietary and environmental factors that affect the sexual selection as well as sexual dimorphism, specifically in reptiles. Sexual selection is a type of natural selection where one sex does the choosing of mates for the other sex, and members of the same sex are rooted against each other to compete for mates. In order for a mate to attract a female with a high reproductive fitness, it is important to do a little showing off, and this is where sexual dimorphism comes in. Sexual dimorphism is the differences between two sexes of the same species. There are many ways in which reptiles can exhibit sexual dimorphism,

Over many years there has been an enormous amount of information gathered from studies, that shows that articulation of traits of sexual selection and sexual dimorphism are extremely dependent on the lizard, or particular organisms diet. However, many of the studies done in the past have failed to show exactly how diet, in fact influences these processes and well known and studied mechanisms. Recently, the idea that nutritional resources such as caloric intake are in single form has been challenged by a modern view that how theses specific forms of energy are taken in influences how the specific traits are expressed, which then regulate sexual selection and sexual dimorphism in a certain manner (Rapkin 1990). It is known that sexual selection is what encourages sex differences and this actually requires that there are different ways that nutrients are taken in. It is important to note, as shown in a study on lizards, that the more modes or methods that are required to intake different nutrients to carry out sexual selection, the more energy that is required of the lizard or any other organism for that matter. In the long run, the energy spent used to take in nutrients has an impact on the organisms homeostatic

This is because many reptiles are ectothermic regulators, which means they require a more constant temperature in the environment to maintain their homeostasis and carry out very important physiological processes. Let’s take a look at how climate change can specifically alter lizards and their sexual selection. With lizards having a reproductive time frame which is usually arrow short spanning through the spring and summer seasons. If the weather changes and makes the breeding season short due to an early onset of cool weather, many lizards may not have enough time to find a mate; this lowers their reproductive fitness. These temperature changes may also cause a huge problem with sexual selection and mating if it causes the sex ratios to get completely out of balance. The climate change and shortened breeding season has been shown in a study done in Oregon, done on the Commin Side-blotched lizard, which I believe we saw often on our weekly field trips for lab (Zani 2005). The same situation was also repeated in another correlated study done in New Mexico on the same species of lizards, the Side-Blotched. In this study, 12% of the lizard population in the area were lost (Sinervo 2010). With this obvious loss of population, there has to be a huge loss of evolutionary reproductive