Sexual dimorphism

Sexual dimorphism in body size between males and females helps contribute to both natural and sexual selection for reproductive advantage. However, it is not known why these differences exist in most species and how it may be controlled. Several case studies were performed on Sceloporus lizards, including those of male-larger species and female-larger species, as well as the Western diamond-backed rattlesnake, Crotalus atrox, which is a male-larger species. The main question revolves around whether sexual size dimorphism, SSD, is predominantly influenced by genetic or environmental causes. Possible determinants for SSD in these squamate reptiles may be the availability of food, amount of testosterone in the body, and/or the portion of energy used for growth or reproduction (John-Alder et al. 2007).…

Sexual dimorphism refers to a species distinct differences between the sexes resulting in distinct male and female forms. This is the sexual selection, adaptive changes in males and females often due to male competition and female selectivity. (Biology, Sylvia s mader and Michael winderlspecht pg 297 - 298). Usually this is the result of phenotype selection but, this is tied in with the selection of genotypes. Size and colorations of features in a mate may indicate features that are not readily…

They hypothesized that the difference in bill curvature between the sexes would be greater for the species with the longest bills and questioned if this dimorphism is formed through sexual selection or natural selection (Temeles, Miller, and Rifkin). This research is crucial because it could explain the diversity in hummingbird species and seeks to understand the forces that have and continue to shape the formation of…

Introduction 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…

if the male frog finds that there are small tadpoles in an axil, it will then grant one of the tadpoles permission to climb onto its back, where it will transport a tadpole to a different location. When the male frog moves the tadpole it will starve, because they are reliant on the food it receives from its mother. Dendrobates pumilio can secure a territory of about 0.24 to 4.78 m squared, which can include perches, foraging sites, and tadpole rearing sites. In comparison, females can take up…

The article described that transcripts initiated from the most distal P1 promoter (in the fru gene) are spliced differently in males and females thus making the fru gene a sexual specific spliced gene. This fact about the fru gene has allowed the author’s of this article to hypothesize that specific splicing of the fru P1 transcripts elicits male courtship behavior and sexual orientation. The article continues on to perform experiments (using mutant fru alleles) to determine if their hypothesis…

INTRODUCTION ` Human Sexual dimorphism as its basic element of identity is genetically determined and determines the natural path of social development and cultural heritage. Complementarity of the morphological phenotype characteristics and behavioral of the men and women is part of the genetic program of human nature-oriented implementation of the basic tasks to fulfill in life, which is to have offspring, which in turn is, related to its fertility. This consists of the ability to produce…

The results showed that there was a significant effect of music on math. Participants who listened to music performed better than participants who completed the tasks without music. One possible explanation of these results is that participants who performed the tasks with music first felt the overall task was too long. As the participants started to inch towards the end, their attention began to dwindle. However, participants who listened to the music last felt a boost of energy once the music…

Scientists have typically believed that sex differences are solely based on biological features, such as genes, hormones, and the brain. People never really believed that environmental influences could have an effect on something that is biologically determined. However, within Wade’s essay “The New Science of Sex Difference,” Wade analyzes the biological bases, such as genes, hormones, and brains, in which she explores the effects these mechanisms have under different social factors.…

The article itself is incorrect in it’s usage of the term “gender,” when it reality it is explaining the differences in biological sex. The article “Distinguishing Gender,” (2011) though dealing with gender and politics, sums up a problem that is also present in the psychology community, “Despite its importance for many public policy choices, the majority of scholarship in political science does not adequately distinguish, either theoretically or methodologically, between the concepts of sex,…