> For the complete documentation index, see [llms.txt](https://weiwey.gitbook.io/whitepaper/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://weiwey.gitbook.io/whitepaper/economy/nft/animals/evolution.md).

# Evolution

### Description

Animals have two evolutionary stages

* Juvenile
* Adult

#### Juvenile

The juvenile cannot participate in production cycles and has no sex

#### Adult

An adult can participate in the production cycles of machines and automatic production cycles of animals

#### Evolution process

To transform a juvenile into an adult, the user must have an NFT evolution potion and carry out the evolution process in the WeiWey personal account by making a transaction to replace the juvenile's NFT with the adult's NFT

After the evolutionary process, an adult will be assigned one of the possible genders

At the same time, the NFT of the young individual is deleted

![An example of animal evolution](https://302346926-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2F7LY7u912YLFq8ZpT2G3U%2Fuploads%2FiLK2HNN9hZZ5yHEClNuw%2FFrame%204.png?alt=media\&token=3609c0a6-77ba-4ceb-a11a-507d3c6ab6dd)