Palaeocastor
Encyclopedia
Palaeocastor is an extinct genus
of beaver
that lived in the North American Badlands
during the late Oligocene
period.
, Palaeocastor was predominantly a burrowing animal instead of an aquatic animal. Fossil evidence suggests that they may have lived in family groups like modern beavers and employed a k reproductive strategy
instead of the normal r-strategy of most rodent
s.
, in 1891 and 1892. Then he described it as giant freshwater sponges. This identification was influenced by the surroundings where the "screws" were situated:the deposits in which they occur were laid down in immense freshwater lakes in the Miocene Epoch, 20 million years ago. Also for a while, people tended to believe the spiral forms are a curious type of extinct vegetation, although many remain skeptical as well.
In 1893, Dr. Thomas Barbour proposed that the Devil's Corkscrew were the burrows of a large rodent
, and Latinized the name to the ichnofossil name Daimonhelix or Daimonelix or Daemonelix (all these spellings are found) and classified them by shape and size.
The dispute on its real identity ceased when a fossilized beaver was discovered in one of them. And the scratches which previously misinterpreted as claw marks are also strong evidence of the existence of Palaeocastor in contrast to the modern castor.
They excavated their burrows with their incisors, not their claws.
Genus
In biology, a genus is a low-level taxonomic rank used in the biological classification of living and fossil organisms, which is an example of definition by genus and differentia...
of beaver
Beaver
The beaver is a primarily nocturnal, large, semi-aquatic rodent. Castor includes two extant species, North American Beaver and Eurasian Beaver . Beavers are known for building dams, canals, and lodges . They are the second-largest rodent in the world...
that lived in the North American Badlands
Badlands
A badlands is a type of dry terrain where softer sedimentary rocks and clay-rich soils have been extensively eroded by wind and water. It can resemble malpaís, a terrain of volcanic rock. Canyons, ravines, gullies, hoodoos and other such geological forms are common in badlands. They are often...
during the late Oligocene
Oligocene
The Oligocene is a geologic epoch of the Paleogene Period and extends from about 34 million to 23 million years before the present . As with other older geologic periods, the rock beds that define the period are well identified but the exact dates of the start and end of the period are slightly...
period.
Habitat
This creature made corkscrew-shaped burrows and tunnels. Like many early castoridsCastoridae
The family Castoridae contains the two living species of beaver and their fossil relatives. This was once a highly diverse group of rodents, but is now restricted to a single genus, Castor.- Characteristics :...
, Palaeocastor was predominantly a burrowing animal instead of an aquatic animal. Fossil evidence suggests that they may have lived in family groups like modern beavers and employed a k reproductive strategy
R/K selection theory
In ecology, r/K selection theory relates to the selection of combinations of traits in an organism that trade off between quantity or quality of offspring...
instead of the normal r-strategy of most rodent
Rodent
Rodentia is an order of mammals also known as rodents, characterised by two continuously growing incisors in the upper and lower jaws which must be kept short by gnawing....
s.
"Devil's Corkscrews"
The discovery of Palaeocastor sprung from the discovery of Devil's Corkscrews in the plains of Sioux County, Nebraska, as a tree-sized, screw-like underground formation. The basic form of it is an elongate spiral of hardened earth material that inserts into the soil as deep as 3 meters. These puzzling structure came first to the notice of science through Dr. E. H. Barbour of the University of Nebraska around Harrison, NebraskaHarrison, Nebraska
Harrison is a village in Sioux County, Nebraska, United States. The population was 279 at the 2000 census. It is the county seat of Sioux County.-Geography:Harrison is located at ....
, in 1891 and 1892. Then he described it as giant freshwater sponges. This identification was influenced by the surroundings where the "screws" were situated:the deposits in which they occur were laid down in immense freshwater lakes in the Miocene Epoch, 20 million years ago. Also for a while, people tended to believe the spiral forms are a curious type of extinct vegetation, although many remain skeptical as well.
In 1893, Dr. Thomas Barbour proposed that the Devil's Corkscrew were the burrows of a large rodent
Rodent
Rodentia is an order of mammals also known as rodents, characterised by two continuously growing incisors in the upper and lower jaws which must be kept short by gnawing....
, and Latinized the name to the ichnofossil name Daimonhelix or Daimonelix or Daemonelix (all these spellings are found) and classified them by shape and size.
The dispute on its real identity ceased when a fossilized beaver was discovered in one of them. And the scratches which previously misinterpreted as claw marks are also strong evidence of the existence of Palaeocastor in contrast to the modern castor.
They excavated their burrows with their incisors, not their claws.