page_title: Snake
section_title: Sidewinding
hierarchical_section_title: Snake / Behavior / Locomotion / Sidewinding
caption_attribution_description: English: A neonate Colorado desert sidewinder (Crotalus cerastes laterorepens) sidewinds across sand. Taken at Zoo Atlanta.
context_page_description: Snakes are elongated, legless, carnivorous reptiles of the suborder Serpentes. Like all other squamates, snakes are ectothermic, amniote vertebrates covered in overlapping scales. Many species of snakes have skulls with several more joints than their lizard ancestors, enabling them to swallow prey much larger than their heads with their highly mobile jaws. To accommodate their narrow bodies, snakes' paired organs appear one in front of the other instead of side by side, and most have only one functional lung. Some species retain a pelvic girdle with a pair of vestigial claws on either side of the cloaca. Lizards have evolved elongate bodies without limbs or with greatly reduced limbs about twenty-five times independently via convergent evolution, leading to many lineages of legless lizards. Legless lizards resemble snakes, but several common groups of legless lizards have eyelids and external ears, which snakes lack, although this rule is not universal.
context_section_description: Most often employed by colubroid snakes (colubrids, elapids, and vipers) when the snake must move in an environment that lacks irregularities to push against (rendering lateral undulation impossible), such as a slick mud flat, or a sand dune, sidewinding is a modified form of lateral undulation in which all of the body segments oriented in one direction remain in contact with the ground, while the other segments are lifted up, resulting in a peculiar "rolling" motion. This mode of locomotion overcomes the slippery nature of sand or mud by pushing off with only static portions on the body, thereby minimizing slipping. The static nature of the contact points can be shown from the tracks of a sidewinding snake, which show each belly scale imprint, without any smearing. This mode of locomotion has very low caloric cost, less than ⅓ of the cost for a lizard to move the same distance. Contrary to popular belief, there is no evidence that sidewinding is associated with the sand being hot.
caption: A neonate sidewinder rattlesnake (Crotalus cerastes) sidewinding.
exif: {"Image Make": "FUJIFILM", "Image Model": "FinePix HS50EXR", "Image Orientation": "Horizontal (normal)", "Image XResolution": "72", "Image YResolution": "72", "Image ResolutionUnit": "Pixels/Inch", "Image Software": "Digital Camera FinePix HS50EXR Ver1.00", "Image DateTime": "2014:07:03 11:13:58", "Image Artist": "Henry Astley", "Image YCbCrPositioning": "Co-sited", "Image Copyright": "", "Image ExifOffset": "2376", "Image XPAuthor": "Henry Astley", "Image PrintIM": "[80, 114, 105, 110, 116, 73, 77, 0, 48, 50, 53, 48, 0, 0, 2, 0, 2, 0, 1, 0, 0, 0, 1, 1, 0, 0, 0, 0]", "Image Padding": "[]", "Thumbnail Compression": "JPEG (old-style)", "Thumbnail Orientation": "Horizontal (normal)", "Thumbnail XResolution": "72", "Thumbnail YResolution": "72", "Thumbnail ResolutionUnit": "Pixels/Inch", "Thumbnail JPEGInterchangeFormat": "6068", "Thumbnail JPEGInterchangeFormatLength": "1958", "Thumbnail YCbCrPositioning": "Co-sited", "EXIF ExposureTime": "1/150", "EXIF FNumber": "16/5", "EXIF ExposureProgram": "Program Normal", "EXIF ISOSpeedRatings": "400", "EXIF SensitivityType": "Standard Output Sensitivity", "EXIF ExifVersion": "0230", "EXIF DateTimeOriginal": "2014:08:12 10:58:41", "EXIF DateTimeDigitized": "2014:08:12 10:58:41", "EXIF ComponentsConfiguration": "YCbCr", "EXIF CompressedBitsPerPixel": "16/5", "EXIF ShutterSpeedValue": "727/100", "EXIF ApertureValue": "17/5", "EXIF BrightnessValue": "209/50", "EXIF ExposureBiasValue": "0", "EXIF MaxApertureValue": "3", "EXIF MeteringMode": "Pattern", "EXIF LightSource": "Unknown", "EXIF Flash": "Flash did not fire, compulsory flash mode", "EXIF FocalLength": "32/5", "EXIF SubSecTimeOriginal": "60", "EXIF SubSecTimeDigitized": "60", "EXIF FlashPixVersion": "0100", "EXIF ColorSpace": "sRGB", "EXIF ExifImageWidth": "4608", "EXIF ExifImageLength": "3456", "Interoperability InteroperabilityVersion": "[48, 49, 48, 48]", "EXIF InteroperabilityOffset": "5860", "EXIF FocalPlaneXResolution": "7166", "EXIF FocalPlaneYResolution": "7166", "EXIF FocalPlaneResolutionUnit": "3", "EXIF SensingMethod": "One-chip color area", "EXIF FileSource": "Digital Camera", "EXIF SceneType": "Directly Photographed", "EXIF CustomRendered": "Normal", "EXIF ExposureMode": "Auto Exposure", "EXIF WhiteBalance": "Auto", "EXIF SceneCaptureType": "Standard", "EXIF Sharpness": "Normal", "EXIF SubjectDistanceRange": "0", "EXIF Padding": "[]", "EXIF OffsetSchema": "4174"}