How is earthworms carrying out gas through their skin an efficient way of carrying out gas exchange?

Earthworms carry out gas exchange efficiently through their skin because their skin is thin and moist, allowing oxygen to easily diffuse into their bodies while carbon dioxide diffuses out. This method eliminates the need for specialized respiratory organs, conserving energy and resources. Additionally, earthworms have a large surface area relative to their volume, which enhances the effectiveness of gas exchange in their burrowing environment. Overall, this adaptation supports their survival in soil habitats where oxygen levels can be variable.