How do you get the gold plaque for exceptional animal diversity in zoo tycoon ds?

To earn the gold plaque for exceptional animal diversity in Zoo Tycoon DS, you need to have at least 40 different animal species in your zoo. Ensure that these species are spread across various habitats and meet their needs for space, food, and enrichment. Additionally, maintaining a high visitor satisfaction level will help in achieving this goal. Keep an eye on your zoo's overall performance to maximize your chances of obtaining the plaque.