page_title: Animal
section_title: Diversity
hierarchical_section_title: Animal / Diversity
caption_attribution_description: Latina: Balaenoptera musculus Polski: Płetwal błękitny English: Blue whale
context_page_description: Animals are multicellular eukaryotic organisms that form the biological kingdom Animalia. With few exceptions, animals consume organic material, breathe oxygen, are able to move, can reproduce sexually, and grow from a hollow sphere of cells, the blastula, during embryonic development. Over 1.5 million living animal species have been described—of which around 1 million are insects—but it has been estimated there are over 7 million animal species in total. Animals range in length from 8.5 micrometres to 33.6 metres. They have complex interactions with each other and their environments, forming intricate food webs. The kingdom Animalia includes humans but in colloquial use the term animal often refers only to non-human animals. The scientific study of animals is known as zoology.
  Most living animal species are in Bilateria, a clade whose members have a bilaterally symmetric body plan. The Bilateria include the protostomes—in which many groups of invertebrates are found, such as nematodes, arthropods, and molluscs—and the deuterostomes, containing both the echinoderms as well as the chordates, the latter containing the vertebrates.
caption: The blue whale is the largest animal that has ever lived.
exif: {"Image ImageWidth": "3072", "Image ImageLength": "2048", "Image BitsPerSample": "[8, 8, 8]", "Image PhotometricInterpretation": "2", "Image Orientation": "Horizontal (normal)", "Image SamplesPerPixel": "3", "Image XResolution": "72", "Image YResolution": "72", "Image ResolutionUnit": "Pixels/Inch", "Image Software": "Adobe Photoshop CS5 Windows", "Image DateTime": "2016:04:03 15:11:29", "Image Copyright": "This image is in the public domain and cannot be copyrighted.", "Image ExifOffset": "304", "Thumbnail Compression": "JPEG (old-style)", "Thumbnail XResolution": "72", "Thumbnail YResolution": "72", "Thumbnail ResolutionUnit": "Pixels/Inch", "Thumbnail JPEGInterchangeFormat": "454", "Thumbnail JPEGInterchangeFormatLength": "0", "EXIF ExifVersion": "0221", "EXIF ColorSpace": "sRGB", "EXIF ExifImageWidth": "2600", "EXIF ExifImageLength": "1950"}