File:Cormohipparion occidentale (sturdy three-toed horse) foot bones (Ash Hollow Formation, Miocene, 11.83 Ma; Ashfall Fossil Beds, Nebraska, USA).jpg
![File:Cormohipparion occidentale (sturdy three-toed horse) foot bones (Ash Hollow Formation, Miocene, 11.83 Ma; Ashfall Fossil Beds, Nebraska, USA).jpg](https://upload.wikimedia.org/wikipedia/commons/thumb/b/b5/Cormohipparion_occidentale_%28sturdy_three-toed_horse%29_foot_bones_%28Ash_Hollow_Formation%2C_Miocene%2C_11.83_Ma%3B_Ashfall_Fossil_Beds%2C_Nebraska%2C_USA%29.jpg/223px-Cormohipparion_occidentale_%28sturdy_three-toed_horse%29_foot_bones_%28Ash_Hollow_Formation%2C_Miocene%2C_11.83_Ma%3B_Ashfall_Fossil_Beds%2C_Nebraska%2C_USA%29.jpg?20221112192334)
Original file (998 × 2,682 pixels, file size: 1.57 MB, MIME type: image/jpeg)
Captions
Captions
Summary
[edit]DescriptionCormohipparion occidentale (sturdy three-toed horse) foot bones (Ash Hollow Formation, Miocene, 11.83 Ma; Ashfall Fossil Beds, Nebraska, USA).jpg |
English: Cormohipparion occidentale (Leidy, 1856) - sturdy three-toed horse foot bones from the Miocene of Nebraska, USA.
This fossil horse foot was excavated from a volcanic ash deposit at Nebraska's Ashfall Fossil Beds. The ash was derived from the Bruneau-Jarbidge Volcanic Field in southwestern Idaho's Snake River Plain. The wind-blown ash buried a vertebrate-rich biota at what was originally a Miocene waterhole. From exhibit info.: EVOLUTION IN ACTION - HORSE FEET - Was Darwin right? Today's horses have a single toe (hoof) on each foot. Scientists of Darwin's day predicted that ancestral horses with more toes would someday be found as fossils. Ashfall proved them right! As you can see in these front feet of horse skeletons from the ash bed, most kinds had 3 toes but one has a single hoof. Sturdy Three-toed Horse Cormohipparion Nebraska-born paleontologist Morris Skinner collected and studied fossil horses for more than 50 years. One of his greatest discoveries was a series of well-preserved skulls of Nebraska horses apparently ancestral to the "Hipparion" horses of Europe and Asia. Other paleontologists had been forced to rely mostly on teeth in researching horse evolution but Skinner pointed out important details of the skull - especially the position and shape of depressions in front of the eye socket. Announcing this discovery in 1977, Skinner and a younger colleague Bruce MacFadden named Cormohipparion. The first complete skeletons of this animal have been found here at Ashfall. These show that the foot bones of Cormohipparion were shorter than those of Neohipparion, a horse with very similar teeth. Remains of this animal have been found: X In the "RECOVERY" layer (sandstone above the ash) X In the "DISASTER" layer (volcanic ash bed) X In the "WATERHOLE" layer (sandstone below the ash) Cormohipparion was about 3.5 feet (1.1 meters) at the shoulder. The Ashfall species, Cormohipparion occidentale, has one of the most complicated enamel patterns on the grinding teeth of any North American horse species. This would help grind grass into small, digestible fragments. A deep pocket in the skull far forward of the eye is characteristic of this horse. Cormo means "stem" and Hipparion is the name of the 3-toed grazing horse of the Old World. Classification: Animalia, Chordata, Vertebrata, Mammalia, Perissodactyla, Equidae Stratigraphy: Cap Rock Member, Ash Hollow Formation, Ogallala Group, Miocene, 11.83 Ma Locality: Ashfall Fossil Beds State Historical Park, northeastern Nebraska, USA Info. at: en.wikipedia.org/wiki/Ashfall_Fossil_Beds |
Date | |
Source | https://www.flickr.com/photos/47445767@N05/52321137670/ |
Author | James St. John |
Licensing
[edit]![w:en:Creative Commons](https://upload.wikimedia.org/wikipedia/commons/thumb/7/79/CC_some_rights_reserved.svg/90px-CC_some_rights_reserved.svg.png)
![attribution](https://upload.wikimedia.org/wikipedia/commons/thumb/1/11/Cc-by_new_white.svg/24px-Cc-by_new_white.svg.png)
- You are free:
- to share – to copy, distribute and transmit the work
- to remix – to adapt the work
- Under the following conditions:
- attribution – You must give appropriate credit, provide a link to the license, and indicate if changes were made. You may do so in any reasonable manner, but not in any way that suggests the licensor endorses you or your use.
![]() |
This image was originally posted to Flickr by James St. John at https://flickr.com/photos/47445767@N05/52321137670. It was reviewed on 12 November 2022 by FlickreviewR 2 and was confirmed to be licensed under the terms of the cc-by-2.0. |
12 November 2022
File history
Click on a date/time to view the file as it appeared at that time.
Date/Time | Thumbnail | Dimensions | User | Comment | |
---|---|---|---|---|---|
current | 19:23, 12 November 2022 | ![]() | 998 × 2,682 (1.57 MB) | Ser Amantio di Nicolao (talk | contribs) | Uploaded a work by James St. John from https://www.flickr.com/photos/47445767@N05/52321137670/ with UploadWizard |
You cannot overwrite this file.
File usage on Commons
There are no pages that use this file.
Metadata
This file contains additional information such as Exif metadata which may have been added by the digital camera, scanner, or software program used to create or digitize it. If the file has been modified from its original state, some details such as the timestamp may not fully reflect those of the original file. The timestamp is only as accurate as the clock in the camera, and it may be completely wrong.
Camera manufacturer | NIKON CORPORATION |
---|---|
Camera model | NIKON D70s |
Exposure time | 1/125 sec (0.008) |
F-number | f/5.6 |
ISO speed rating | 200 |
Date and time of data generation | 12:37, 5 August 2011 |
Lens focal length | 200 mm |
Width | 2,000 px |
Height | 3,008 px |
Bits per component |
|
Pixel composition | RGB |
Orientation | Normal |
Number of components | 3 |
Horizontal resolution | 300 dpi |
Vertical resolution | 300 dpi |
Software used | Adobe Photoshop Elements 18.0 (Macintosh) |
File change date and time | 02:17, 29 August 2022 |
Y and C positioning | Co-sited |
Exposure Program | Not defined |
Exif version | 2.21 |
Date and time of digitizing | 12:37, 5 August 2011 |
Meaning of each component |
|
Image compression mode | 4 |
APEX shutter speed | 6.965784 |
APEX aperture | 4.970854 |
APEX exposure bias | 0 |
Maximum land aperture | 5 APEX (f/5.66) |
Metering mode | Pattern |
Light source | Unknown |
Flash | Flash fired, strobe return light detected, auto mode |
DateTime subseconds | 00 |
DateTimeOriginal subseconds | 00 |
DateTimeDigitized subseconds | 00 |
Supported Flashpix version | 1 |
Color space | sRGB |
Sensing method | One-chip color area sensor |
File source | Digital still camera |
Scene type | A directly photographed image |
Custom image processing | Normal process |
Exposure mode | Auto exposure |
White balance | Auto white balance |
Digital zoom ratio | 1 |
Focal length in 35 mm film | 300 mm |
Scene capture type | Standard |
Scene control | None |
Contrast | Normal |
Saturation | Normal |
Sharpness | Normal |
Subject distance range | Unknown |
Serial number of camera | 200638ad |
Lens used | 18.0-200.0 mm f/3.5-5.6 |
Date metadata was last modified | 22:17, 28 August 2022 |
Unique ID of original document | 010ECD20772DF80875B8A0450030EFF8 |