page_title: Timeline of the evolutionary history of life
section_title: Proterozoic Eon
hierarchical_section_title: Timeline of the evolutionary history of life / Detailed timeline / Proterozoic Eon
caption_attribution_description: This file was uploaded with Commonist. English: Blepharisma japonicum, Heterotrichea, Ciliophora Deutsch: Blepharisma japonicum, Heterotrichea, Ciliophora
context_page_description: This timeline of the evolutionary history of life represents the current scientific theory outlining the major events during the development of life on planet Earth. In biology, evolution is any change across successive generations in the heritable characteristics of biological populations. Evolutionary processes give rise to diversity at every level of biological organization, from kingdoms to species, and individual organisms and molecules, such as DNA and proteins. The similarities between all present day organisms indicate the presence of a common ancestor from which all known species, living and extinct, have diverged through the process of evolution. More than 99 percent of all species, amounting to over five billion species, that ever lived on Earth are estimated to be extinct. Estimates on the number of Earth's current species range from 10 million to 14 million, of which about 1.2 million have been documented and over 86 percent have not yet been described. However, a May 2016 scientific report estimates that 1 trillion species are currently on Earth, with only one-thousandth of one percent described.
context_section_description: 2500 Ma – 542 Ma. Contains the Palaeoproterozoic, Mesoproterozoic and Neoproterozoic eras.
caption: Blepharisma japonicum, a free-living ciliated protozoan
exif: {"Image ImageWidth": "3744", "Image ImageLength": "5616", "Image BitsPerSample": "[8, 8, 8]", "Image PhotometricInterpretation": "2", "Image Make": "Canon", "Image Model": "Canon EOS 5D Mark II", "Image Orientation": "Horizontal (normal)", "Image SamplesPerPixel": "3", "Image XResolution": "300", "Image YResolution": "300", "Image ResolutionUnit": "Pixels/Inch", "Image Software": "Adobe Photoshop CS5.1 Macintosh", "Image DateTime": "2012:05:04 19:34:49", "Image YCbCrPositioning": "Co-sited", "Image ExifOffset": "308", "GPS GPSVersionID": "[2, 2, 0, 0]", "Image GPSInfo": "1076", "Thumbnail Compression": "JPEG (old-style)", "Thumbnail XResolution": "72", "Thumbnail YResolution": "72", "Thumbnail ResolutionUnit": "Pixels/Inch", "Thumbnail JPEGInterchangeFormat": "1190", "Thumbnail JPEGInterchangeFormatLength": "7498", "EXIF ExposureTime": "1/250", "EXIF FNumber": "0", "EXIF ExposureProgram": "Aperture Priority", "EXIF ISOSpeedRatings": "400", "EXIF ExifVersion": "0221", "EXIF DateTimeOriginal": "2012:04:30 08:25:54", "EXIF DateTimeDigitized": "2012:04:30 08:25:54", "EXIF ComponentsConfiguration": "YCbCr", "EXIF ShutterSpeedValue": "8", "EXIF ApertureValue": "2147483648", "EXIF ExposureBiasValue": "0", "EXIF MeteringMode": "Pattern", "EXIF Flash": "Flash did not fire, compulsory flash mode", "EXIF FocalLength": "50", "EXIF SubSecTime": "90", "EXIF SubSecTimeOriginal": "90", "EXIF SubSecTimeDigitized": "90", "EXIF FlashPixVersion": "0100", "EXIF ColorSpace": "sRGB", "EXIF ExifImageWidth": "1000", "EXIF ExifImageLength": "667", "Interoperability InteroperabilityIndex": "R98", "Interoperability InteroperabilityVersion": "[48, 49, 48, 48]", "EXIF InteroperabilityOffset": "1044", "EXIF FocalPlaneXResolution": "5616000/1459", "EXIF FocalPlaneYResolution": "1872000/479", "EXIF FocalPlaneResolutionUnit": "2", "EXIF CustomRendered": "Normal", "EXIF ExposureMode": "Auto Exposure", "EXIF WhiteBalance": "Auto", "EXIF SceneCaptureType": "Standard"}