How Do Spiders Change Their Gender?

Spiders differ from other arthropods in that their sex is not determined by a single gene. There are several factors involved in the determination of sex, some of which are genetic and some of which are ecological.

Among the genetic factors implicated in sex determination are Dmrt, csd and tra like genes. These genes are found in the genomes of many species. However, they may not play a major role in the determination of sex.

The core events of sex determination involve X:A ratios, the Dmrt gene and a transcriptional regulator. All these factors are conserved in most arthropods, but they can be varied in spiders.

One of the most interesting characteristics of spiders is their sex differences. Females are generally larger and fecund than males. Larger females produce more eggs, allowing more generations.

Another difference is the size of the genitals of large females. This entails challenges for both sexes during copulation. Some species show extreme sexual size dimorphism. Smaller males are more likely to become meals.

Male spiders also have a great variety of behavior. They may be polyandrous, storing sperm from different males. In addition, males can carry ornaments, which attract females. And they risk lives to find mates.

As part of their mating rituals, some spiders amputate their palps. This helps them move faster and increase mobility. Male jumping spiders also vibrate their palps to create a syringe-like structure.

Some spiders have a glowing patch in the front of their body, which attracts mates. Others have epigynes, which are visible before the final molt.