Lubbock Lake was a natural 10 acre body of water located within the city limits of Lubbock, Texas. Wind blown sediment formed a barrier that choked the flow of a stream, creating this lake. Springs fed the stream and were part of the headwaters of the Brazos River system. During the 19th century Lubbock Lake served as a favorite watering hole for cowboys and their cattle, and Indians had utilized these wetlands for at least 13,000 years. But during the 1930s too many residents had dug wells in the vicinity causing the water table to drop and the lake to dry up. City workers dug into the dry lake bed in a failed attempt to establish a reservoir. However, vertebrate fossils and artifacts were found in the spoil piles of dirt dug by the engineers. Scientists began studying this locality. Material from this site was the first ever to be radio-carbon dated. It’s the only site where evidence humans butchered giant short-faced bear and pampathere has ever been found. In 1987 Eileen Johnson published an extensive study of all the data compiled from this site. That’s the source for the information I write about in this blog entry.
Location of the Lubbock Lake Fossil Site. There is a museum administered by Texas Tech near the site which is also known as the Lubbock Lake Landmark.
Scientists looked for fossil pollen throughout the 300 acre area around Lubbock Lake. They wanted to determine what the environment of the area had been like over the past 13,000 years. They had a hard time finding enough pollen to establish a statistically valid pollen data base. Some pine and spruce pollen was found in Pleistocene-dated samples, but scientists can’t agree on interpretations of the meager data they do have. Some plant macrofossils were found in Pleistocene-dated sediments–bulrush, spike rush, seepweed, and netleaf hackberry. This indicates the immediate vicinity of the stream was a brushy marsh.
Fossil remains of netleaf hackberry (Celtis reticulate) were found in Pleistocene-aged sediments at Lubbock Lake. It is a small tree adapted to arid climates.
One scientist analyzed the composition of snail species to determine how the local environment has changed over the past 13,000 years. Pleistocene-aged strata held 46 species, including 29 land and 17 aquatic snails. All of the aquatic species can still be found in the region, but 3 species of land snails no longer occur here. The silky vallonia (Vallonia cyclophorella) and the moss chrysalis snail (Pupilla muscorum) no longer range this far south. Vertigo gouldi basidens (a snail with no common name) is currently restricted to high elevations in Colorado, Montana, and New Mexico. The retreat of these 3 species from the Lubbock Lake site suggests a cooler moister climate existed here during the Late Pleistocene.
The moss chrysalis snail (Pupilla muscorum). Shells of this species were found in Pleistocene-aged strata at this site. It no longer ranges this far south.
The composition of the vertebrate fossils found in the Pleistocene-aged strata indicates the southern high plains environment was mostly grassland and desert with some brush and wetland habitats. There are no representative species definitively representative of woodland or forested habitats, so I doubt pine and spruce trees were present in significant numbers. Mammoth, bison, horse, camel, pronghorn, prairie dog, ground squirrel, jack rabbit, desert cottontail, burrowing owl, and tortoise prefer arid prairie habitat. Herds of bison and pronghorns drank from Lubbock Lake until the end of the 19th century. Based on this faunal composition, I believe the environment has changed little at this location since 13,000 years ago, though summers have gotten much hotter than they were during the Ice Age.
Eight species of extant vertebrates that lived near Lubbock Lake during the Late Pleistocene no longer occur here. Meadow voles, southern bog lemmings, and prairie voles can’t tolerate the present day summer temperatures that can reach 100 degrees F. Richardson’s ground squirrels have retreated to higher elevations. Box turtles and common garter snakes can’t endure high heat without the shade of trees. Eileen Johnson believes late Pleistocene summer temperatures here were on average 10 degrees F cooler than those of the present day. There was also more frequent cloud cover. I agree with this assumption but disagree with her assumption that Ice Age winters here were frost free.
She bases this belief on the presence of giant tortoise and pampathere (a species of giant armadillo) in the fossil record. She assumes neither species could have survived a frost. She stated they both were too large to have dug burrows that would have helped them escape freezing temperatures. This is a curious assumption–grizzly bears grow larger than pampatheres, and they dig dens. Since Dr. Johnson’s study was published, evidence pampatheres dug burrows has been found in southern Brazil, demonstrating they could have survived freezing temperatures by digging burrows. And on previous blog posts, I’ve challenged the widely held assumption that giant tortoises couldn’t survive subfreezing temperatures. (See:https://markgelbart.wordpress.com/2011/04/15/the-extinct-pleistocene-giant-tortoise-hesperotestudo-crassicutata-must-have-been-able-to-survive-light-frosts/) The giant tortoises were closely related to gopher tortoises, a species that does dig burrows; and I’m unaware of any anatomical studies that determined whether or not the giant tortoises were capable of digging. Moreover, giant tortoises could have utilized burrows dug by giant ground sloths or pampatheres. I believe winter temperatures at Lubbock Lake during the Ice Age were the same or just slightly milder due to greater cloud cover than those of the present day.
The most unusual vertebrate fossil found at Lubbock Lake was a specimen of the gray-breasted crake (Laterallus exilis), a bird that is presently restricted to parts of Central and South America. During the Ice Age large lakes were abundant in southwestern North America because glacially cooled air collided with hot desert air, resulting in increased precipitation and cool cloudy conditions. The gray-breasted crake prefers grassy marshes adjacent to lakes. This bird along with many other species of waterfowl occurred in great numbers along these lakeshore habitats. Wandering flocks and individuals of these species also populated the more meager wetlands found on the southern high plains, the region adjacent to the land of great lakes.
Remains of gray-breasted crake were found at the Lubbock Lake site. This was the most surprising faunal find at this site. Today, the range of this species includes parts of Central and South America.
Map of Pleistocene lakes in southwestern North America. Cooler summer temperatures meant lower evapotranspiration rates, resulting in these abundant lakes then. This probably explains the occurrence of several aquatic bird species found in Pleistocene-aged strata at Lubbock Lake.
Several areas within the Lubbock Lake site have been interpreted as megafaunal meat processing stations. A station buried in Late Pleistocene sediment was used by members of the Clovis Culture. They apparently butchered mammoths, bison, horse, half-ass, camel, giant short-faced bear, pampathere, turtles, and turkey here. They butchered a 25 year old mammoth along with 2 juveniles. A camel leg bone was broken and gouged for marrow. Ribs of bison, camel, and horse showed evidence of de-fleshing. A bear bone had knife cut marks on it, and the Indians actually made a tool from a bear bone. Eighteen shells of a large extinct subspecies of box turtle found here show evidence of human modification. I should note that not all anthropologists agree with Dr. Johnson’s interpretation. Some think stream action rolling bones against rocks can mimic the marks made by humans using stone blades.
This is the only known evidence that humans exploited Arctodus simus–the giant short-faced bear. There are knife cut marks on this bear’s leg bone. From the below referenced work.
Assorted Bison antiquus bones. This was the evolutionary predecessor to the modern bison. The Lubbock Lake site has been interpreted as a game processing station used by paleoindians as well as archaic, ceramic, Apache, and Comanche Indians.
These are radio-carbon dates of associated organic material where these Paleo-Indian arrowheads were found. Add about 2000 years for actual calendar year dates.
There is also plenty of evidence that later Folsom, Plainview, Highview, Archaic, Ceramic, Apache, and Comanche Indians also used this site to process game. The Lubbock Lake site has long been the only reliable source of water for miles. This explains why it’s an excellent archaeological site with representative artifacts from every culture that’s lived in the region for the past 13,000 years.
Below is the list of vertebrate species found here in strata dated to between 13,000 BP- 10,000 BP.
quillback–Carpoides cyprinus. This is a type of buffalo fish.
bullhead catfish–Ictalurus amieurus
black bullhead catfish–Ictalurus melas
channel catfish–Ictalurus punctatus
white bass–Morone chrysops
green sunfish–Lepomis cyanellus
warmouth sunfish–L. gulosus
unidentified darter–Percina sp.
tiger salamander–Ambystoma tigrinum
Couch’s spadefoot toad–Scaphiophus couchi
unidentified spadefoot toad–plains or western, Scaphiophus bombifrons or S. hammondi
cricket frog–Acris crepitans
plains toad–Bufo cognatus
woodhouse’s toad–B. woodhousei
pickerel frog–R. palustrus
leopard frog–R. pipiens
snapping turtle–Chelydra serpentine
pond slider–Chrysemys scripta
Wilson’s tortoise–Geochelone? wilsonii (extinct)
extinct giant tortoise–Hesperotestudo sp.
extinct subspecies of eastern box turtle–Terrapene Carolina putnami
ornate box turtle–T. ornate
soft-shelled turtle–Trionyx sp.
Texas horned lizard–Phrynosoma cornutum
Great plains skink–Eumeces obsoleteus
black racer–Coluber constrictor
worm snake–Carphophis amonus
corn snake–Elaphe guttata
western hook-nosed snake–Gyalopion canum
western hog-nosed snake–Heterodon nasicus
king snake–Lampropeltis getulus
milk snake–L. triangulum
unidentified water snake–Nerodia sp.
red bellied water snake–N. erythrogaster
unidentified snake in the Elaphe or Pituphis genus
patch-nosed snake–Salvadora sp.
ground snake–Sonora semiannulata
checkered garter snake–Thamnophis marcianus
common garter snake–T. sirtalis
lined snake–Tropidoclonion lineatum
rough earth snake–Virginia striatula
copperhead snake–Agkistrodon contortix
western diamondback rattlesnake–Crotalus atrox
eared grebe–Podiceps nigricollis
pied-billed grebe–Podilymbus podiceps
Canada goose–Branta Canadensis
snow goose–Anser caerulescens
mallard duck–Anas platyrhincus
gadwall or pintail duck–A. streptera or A. acuta
pintail duck–A. acuta
northern shoveler–A. clypeata
green winged teal–A. crecca
blue-winged teal-A. discors
cinnamon teal–A. cyanoptera
ruddy duck–Oxyura jamaicensis
marsh hawk–Circus cyaneus
unidentified galliforme–either a prairie chicken or sharp-tailed grouse
Virginia rail–Rallus limicola
clapper rail–R. longirostris
sora rail–Porzana Carolina
gray-breasted crake–Laterallus exilis
common gallinule–Gallinula chloropus
mountain plover–Charadrius montanus
burrowing owl–Athene cunicularia
common nighthawk–Chordeiles minor
northern flicker–Colaptes auratus
horned lark–Eremophilia alpestris
common raven–Corvus corvax
red-winged blackbird–Agelaius phoenicus
brown-headed cowbird–Molothrus ater
vesper sparrow–Poocetes gramicus
unidentified shrew–Blarina sp.
desert shrew–Notiosorex crawfordi
desert cottontail–Sylvilagus audubonii
blacktail jackrabbit–Lepus californicus
Richardson’s ground squirrel–Spermophilus richardsonii
13-lined ground squirrel–S. tridecemlineatus
Mexican ground squirrel–S. Mexicanus
blacktail prairie dog–Cynomys ladovicianus
valley pocket gopher–Thomomys bottae
plains pocket gopher–Geomys bursarius
hispid pocket mouse–Perognathus hispidus
Ord’s kangaroo rat–Dipodomys ordii
plains harvest mouse–Reithrodontomys montanus
cactus mouse–Peromyscus eremicus
unidentified field mouse–Peromyscus sp.
northern grasshopper mouse–Onychomys leucogaster
southern plains woodrat–Neotoma micropus
white-throated woodrat–N. albigula
cotton rat–Sigmodon hispidus
meadow vole–Microtus pennsylvanicus
prairie vole–M. ochrogaster
southern bog lemming–Synaptomys cooperi
timber wolf–Canis lupus
kit fox–Vulpes macrotis
giant short-faced bear–Arctodus simus
Columbian mammoth–Mammuthus colombi
flat-headed peccary–Platygonnus compressus
yesterday’s camel–Camelops hesternus
extinct pronghorn–Capromeryx sp.
upland bison–Bison antiquus
whitetail or mule deer–Odocoileus sp.
Lubbock Lake: Late Quaternary Studies on the Southern High Plains
Texas A&M University Press 1987