Lore-Writer's Blog: Sexual Dimorphism in Dragons Part 1 (Patreon)

Top to bottom: Male, Elder Male, Female, Elder Female(Jao made me write the blog this month, so you get a science-y one

-Bad Parrot)Sexual dimorphism, or the physical differences between males and females of a species, is present in many dragon species. Some have obvious distinctions while others may have no distinction at all. The level of sexual dimorphism in a dragon species is determined by their courtship behavior. Most dragon species in Jrakhon exhibit what is known as intersexual selection, also known as "mate choice". During reproduction, Females spend significantly more energy than males gestating eggs. Therefore, females tend to be picky when selecting a potential mate. Sexual dimorphism is one tool females can use to determine the overall fitness of their suitors. For this Lore Writer's blog, we will explore the courtship behavior and sexual dimorphism of the Acid Spitter and Shadow Scale.Acid Spitter's are a non-flighted dragon species, also known as a drake. This species exhibits a form of sexual dimorphism known as sexual dichromatism. This means the males and females of this species exhibit differences in coloration. Male Acid Spitters have a higher amount of blood flow to their frill membranes, giving them a vibrant coloration, while females do not. Instead of investing energy in extra coloration, the female must conserve hers to create the eggs later on in courtship.To show the female his robust fitness, the male will perform a courtship dance, displaying his frill membranes and sharp tail spikes. The Male's vivid coloration displays to the female that the male is healthy and strong enough to help care for her offspring and increase their chance for survival. Healthy tail spikes, mean the male is fit for battle to defend his upcoming brood. If impressed, the female may respond with a similar dance and the next generation of Spitters will be on the way.Shadow Scales are a true dragon species, meaning they have four walking limbs and two flight limbs. These dragons have one of the more subtle forms of sexual dimorphism which is only displayed in their eyes and has little to do with sexual selection and more to do with gene placement on the chromosome. The Z chromosome of the Shadow Scale carries a gene which determines eye pigment. Having two Z sex chromosomes will increase the amount of pigment in the iris, resulting in darker eye coloration. This is why male Shadow Scales (ZZ) will have darker irises than female Shadow Scales (ZW).In the Shadow Scale's courtship behavior, the male will perform a wing flapping motion along with a hop, topped off with an alluring purr. The purr is amplified by how the male holds his head in the display. If done properly, the female will find this combination of dance and vocalization irresistible and copy the male's movements. In part two of the Sexual Dimorphism Blog series, we will discuss the courtship behavior and sexual dimorphism of the Flame Stalker and Inferno Ravager.