Artheropods aren't just the most numerous animals and omnipresent, they are also vital parts of most biotopes. Many are at the basis of food chains like tiny krill, which eats phytoplankton and is eaten by fish and whales. Many are specialized in recycling, like dun beetles and various scavengers. Some transform their environments even at landscape level, link ant and termite colonies. Other regulate bug populations, like spiders. Most important for plant life are pollinators, like bees and butterflies.