What is sexual selection and how does it affect reproductive success? This article discusses the nature of sexual selection, its mechanisms, and how it affects reproductive success. In addition, it explores the history of sexual selection and how it has evolved. Ultimately, you’ll be able to answer the question, “What is sexual selection?” and understand its role in the development of humans and animals.
Nature of sexual selection
Darwin’s theory of sexual selection included two main mechanisms: competition and mate choice. Although Darwin did not explicitly define the two, his theory implicitly argued that the former promotes individual success at the expense of the species as a whole. The latter, on the other hand, promotes display for the benefit of the species as a whole. This theory was criticized by Huxley and Lack, and the theory went into a state of torpor.
In addition to the benefits and costs of sexual selection, it is important to note that natural selection is an extremely powerful force in evolution. While there is no definitive proof that sexual selection is responsible for the evolution of all species, the process is still an important mechanism. The evolution of secondary sexual characters (such as size and sexiness) may contribute to an increased likelihood of mating success.
Several studies have shown that sexual selection favours traits of one sex over the opposite. While this is not universally observed, lab studies have shown that sexually selected traits do affect reproductive success. However, the timing of these traits is important. For instance, an early song increases the chances of mating, but it is energetically costly and increases the risk of predation.
Another important aspect of sexual selection is its correlation between traits. In other words, if two male birds have different plumages, their mating success will determine which is more attractive to females. This means that a male bird with a red or a yellow plumage is more likely to attract females than an identical white male.
Mechanisms
Sexual selection occurs in two ways: male-male competition and female mate choice. Each mechanism is important in the evolution of sexual traits, but they are not identical. In addition, total sexual selection may operate on a trait in a completely different way than either mechanism acting alone. Hence, to understand sexual selection, it is important to understand each of these mechanisms separately.
While the two most common mechanisms of sexual selection – male-male competition and sperm competition – work well on their own, they also interact with each other. For example, male-male competition may interact with female mate choice on different time-scales. Male-male competition is a powerful mechanism of sexual selection in a male-dominated environment, but it can also interact with other processes to influence female choices.
One model explains why leks form around a dominant male. It predicts that females prefer a male that outcompetes other males. It also predicts that females reject males who display alone. These findings are consistent with findings from the Purple Martin study. Sexual selection is important in colony formation because it affects reproductive success and the care of offspring. Moreover, the relative selection gradients of males and females can help explain the degree of sexual dimorphism.
Sexual selection can also affect fecundity, and multiple mating has been shown to increase offspring survival. While polyandry has a positive effect on offspring survival, it does not do so in all environments. If the environment changes rapidly, sexual selection may not be effective enough to protect the population from the change.