Timothy F. H. Allen is a very smart man who has spent his life studying things like plants and animals and how they live together in environments called ecosystems. He tries to understand how everything in an ecosystem works together to make it a healthy and happy place.
Think about a garden. There are plants, like flowers and vegetables, and there are animals that come to the garden, like butterflies and bees. If the garden is healthy, everything works together perfectly, and the plants grow big and strong and the animals have enough food to eat.
Timothy F. H. Allen spends his time studying bigger ecosystems, like forests or coral reefs, to see how everything works together there. He also thinks about how people can make sure that the ecosystems stay healthy and not get hurt by things like pollution or too much hunting or fishing.
Overall, Timothy F. H. Allen is a very important scientist who wants to make sure nature stays healthy and happy for all of us to enjoy.