Rampart Cave

Rampart Cave, located near the western end of the Grand Canyon, once contained one of the most impressive deposits of Pleistocene mammal remains, including bones, skin and hair, and dung known in North America.  Discovered in 1936, the cave was subject of several major research projects until 1976, when an estimated two-thirds of the cave deposits were lost to a months-long fire most likely set by campers or vandals.

Prior to the fire, the dung—mostly from Shasta ground sloths (Nothrotheriops shastensis)—had accumulated to a depth of 20 feet in places and represented two long periods of use, one between 40,000 and 24,000 years ago, and one between 13,000 and 11,000 years ago.

Shasta Ground Sloth Skull. Click to view 3D model.

Shasta ground sloth were around the size of a modern grizzly bear—roughly 9 feet long and weighing more than 500 lbs—and were herbivorous.  Studies of the dung show the sloths ate a variety of desert plants, including globemallow, Mormon tea, saltbush, catclaw, cacti, reeds, and yucca.

Found in the cave deposits were also sloth bones, skin, and hair, and well as the skeletal remains of other extinct Pleistocene mammals, including Harrington’s mountain goat (Oreomnos harringtoni), North American horse (Equus sp.), and a species of vampire bat (Desmodus stocki).

3D models are available for the Shasta ground sloth skull and dung, and for the Harrington’s mountain goat skull, and additional images, including the sloth skin and hair, are available in the galleries below.

Image galleries

Rampart Cave species

Common NameScientific NameExtinct?
American porcupineErethizon dorsata
Bighorn sheepOvis canadensis
BobcatLynx sp.
Brazilian free-tailed batTadarida brasiliensis
ChipmunksEutamias sp.
CottontailSylvilagus sp.
Deer micePeromyscus sp.
Harrington's mountain goatOreamnos harringtonix
JackrabbitLepus sp.
Kangaroo ratsDipodomys sp.
Mastiff batsEumops sp.
Mountain LionPuma concolor
North American horseEquus sp.x
RingtailBassariscus astutus
Shasta ground slothNorthrotheriops shastensisx
SkunkSpilogale sp.
Spermophile ground squirrelsSpermophilus sp.
Stock's vampire batDesmodus stockix
WeaselsMustela sp.
Western pocket gophersThomomys sp.
Woodrats/PackratsNeotoma sp.
Yellow-bellied marmotMarmota flaviventris
Aplomado falconFalco femoralis
Barn owlTyto alba
Black vultureCoragyps atratus
Black-crowned night-heronNycticorax nycticorax
California condorGymnogyps californianus
Golden eagleAquila chryaetos
Red-tail hawkButeo jamaicensis
Turkey vultureCathartes aura
Western vultureCoragyps occidentalisx
Morafka's desert tortoiseGopherus morafkai
ChuckwallaSauromalus ater
Desert spiny lizardSceloporus magister
Gopher snakePituophis catenifer
Long-nosed snakeRhinocheilus lecontei
Northern plateau lizardSceloporus tristichus
Parasites (from sloth dung)
Juvenile, pinworm-like Agamofilaria oxyurax
ProtozoanArcheococcidia antiquusx
ProtozoanArcheococcidia nothrotheriopaex
RoundwormStrongyloides shastensisx
Plants (from sloth dung)
CactiOpuntia sp.
Catclaw acaciaAcacia greggii
Common reedPhragmites communis
Desert globemallowSphaeralcea ambigua
Nevada Mormon teaEphedra nevadensis
SaltbushAtriplex sp.
YuccaYucca sp.
Plants (from packrat middens)
Banana yuccaYucca baccata
BeargrassNolina microcarpa
Beavertail cactusOptunia basilaris
Birchlead buckthornRhamnus betaefolia
BlackbrushColeogyne ramosissima
BrittlebrushEncelia farinosa
Catclaw acaciaAcacia greggii
Desert almondPrunus fasciculata
GlobemallowSphaeralcea sp.
Ground cherryPhysalis sp.
JuniperJuniperus sp.
Knowlton hophornbeamOstrya knowltonii
Little-leaf mountain mahoganyCercocarpus intricatus
Mormon teaEphedra sp.
RabbitbushChrysothamnus sp.
Single-leaf ashFraxinus anomala
SnowberrySymphoricarpos sp.
SquawbushRhus trilobata
ShadscaleAtriplex confertifolia
Utah agaveAgave utahensis
Whipple chollaOptunia whipplei
Wooly-headed barrel cactusEchinocactus polyephalus

Species list derived from:

Carpenter, Mary C. (2003) Late Pleistocene Aves, Chiroptera, Perissodactyla, and Artiodactyla from Rampart Cave, Grand Canyon, Arizona. Master’s Thesis, University of Northern Arizona, Flagstaff.

Hansen, Richard M. (1978) Shasta Ground Sloth Food Habits, Rampart Cave, Arizona. Paleobiology 4(3):302-319.

Kenworthy, J., V. L. Santucci, and K. L. Cole (2004) An Inventory of Paleontological Resources Associated with Caves in Grand Canyon National Park.  In The Colorado Plateau, Cultural, Biological, and Physical Research, edited by C.V. Riper III and K.L. Cole, pp. 211-228. University of Arizona Press, Tucson.

Lindsay, E. H., and N. T. Tessman (1974) Late Cenozoic Vertebrate Localities and Faunas in Arizona. Journal of the Arizona Academy of Science 9:3-24.

Mead, J. I., N. J. Czaplewski, and L. D. Agenbroad (2005) Rancholabrean (Late Pleistocene) Mammals and Localities of Arizona.  In Vertebrate Paleontology of Arizona, edited by R.D. McCord, pp. 139-180. Mesa Southwest Museum Bulletin No. 11.

Miller, L. (1960) Condor Remains from Rampart Cave, Arizona. Condor 62:70.

Phillips, Arthur M., III (1984) Shasta Ground Sloth Extinction: Fossil Packrat Midden Evidence from the Western Grand Canyon.  In Quaternary Extinctions: A Prehistoric Revolution, edited by P.S. Martin and R.G. Klein, pp. 148-158.  University of Arizona Press.

Schmidt, Gerald D., Donald W. Duszynski, and Paul S. Martin (1992) Parasites of the Extinct Shasta Ground Sloth, Nothrotheriops shastensis, in Rampart Cave, Arizona. Faculty Publications from the Harold W. Manter Laboratory of Parasitology. Paper 181. http://digitalcommons.unl.edu/parasitologyfacpubs/181 (link opens in new window).

Van Devender, T. R., A. M. Phillips, and J. I. Mead (1977) Late Pleistocene Reptiles and Small Mammals from the Lower Grand Canyon of Arizona. Southwestern Naturalist 22:49-66.

Wilson, R. W. (1942) Preliminary Study of the Fauna of Rampart Cave, Arizona. Contributions to Paleontology 6. Carnegie Institute of Washington Publication 530:169-185.

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