Animal body lengths range from 8.5 μm (0.00033 in) to 33.6 m (110 ft). They have complex ecologies and interactions with each other and their environments, forming intricate food webs.
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Animals are multicellular eukaryotes whose cells are bound together by collagen. Animals dominate human conceptions of life on Earth because of their size, diversity, abundance, and mobility. The presence of muscles and mobility is one of the primary characteristics of the animal kingdom.
An animal is a complex, multicellular organism that belongs to the biological kingdom Animalia – the animal kingdom. Animals range from relatively simple organisms such as sponges and jellyfish to complex ones such as humans and elephants.