Scientific Classification
Kingdom: Animalia
Phylum: Chordata
Class: Sauropsida
Superorder: Dinosauria
Order: Ornithischia
Genus: Eocursor

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The Eocursor was a basal ornithischian dinosaur that was in existence about 212 to 210 million years. It flourished in the Norian age of the Triassic period of the Mesozoic era. It was present in the African continent.
It was a very small species of dinosaurs that was usually hunted upon by other larger varieties of dinosaurs. The Eocursor had the dimensions of an average sized dog. It had a lean built and was adapted for sprinting at high speeds. This characteristic facilitated catching prey as well as running away from predators.
It most likely had omnivorous feeding habits.
The discovery of the Eocursor was instrumental in understanding other ornithischian dinosaurs. Before the Eocursor was found, very little information was available order Ornithischia. There is more fossil information available about the Eocursor than any other ornithischian dinosaur.

Etymology
According to Greek mythology, ‘Eos’ was the deity of dawn. The word ‘cursor’ translates to ‘runner’ or ‘sprinter’ in Latin. Thus, the word Eocursor indicates ‘runner at dawn’.
The use of the word ‘dawn’ for this dinosaur is probably derived from the fact that it present before other ornithischian dinosaurs and probably paved the way for their prosperity. The incorporation of runner in its name highlights is excellent ability to sprint.
The binomial name Eocursor parvus translates to ‘tiny’ or ‘small’. It was named such owing to its small stature.

Classification
The Eocursor is a primitive ornithischian. The word ‘ornitheos’ translates to ‘of a bird’ and ishion translates to ‘pelvic joint’. So the ornithischians were essentially dinosaurs with hips similar to that of a bird.
The order Ornithischia is one the two major divisions of clade Dinosauria. Until the discovery of the Eocursor, other ornithischians had remained a mystery. It was difficult to determine their evolutionary path.
The Eocursor made such information available for paleontologists.

Discovery of fossils
The fossils of the Eocursor were discovered in the Lower Elliot Formation. This is located in present day Free State which is a province of South Africa.
The remains were discovered in 1993, but they were interpreted and described in detail by Butler, Smith and Norman in 2007. Although much research was conducted on the fossils, there was no consensus about their origins until 2007.

The Elliot Formation
The Elliot Formation is a natural geological structure located in South Africa. It has been crucial in shedding light on the African flora and fauna of the late Triassic and early Jurassic periods. It consists predominantly of limestone, arenite, sandstone, clay and mud.
It is divided into the Upper Elliot Formation and the Lower Elliot Formation. This demarcation is based upon stratigraphic difference between the stones in two different locations.

• Upper Elliot Formation:

The Upper Elliot Formation lacks the deviations in structure and composition that the lower unit has. It is part of the Stromburg group and had comprised of the Karoo basin and the Cape fold belt.
Remains of many sauropod dinosaurs were found in this region. These include Leptospondylus, Massospondylus, Pachyspondylus, Thecodontosaurus, etc. Many ornithischian dinosaurs were also found in the Upper Elliot Formation. These include Lesothosaurus, Lanasaurus, Heterodontosaurus, etc.
It was highly significant in increasing the understanding of the African terrain in the early Mesozoic Era.

• Lower Elliot Formation:

The Lower Elliot Formation is richly diverse not only in its structure but also in the fossils contained in it. It displays lithographic variations laterally, in the north-south sector. The remains of the Eocursor were unearthed here.
Many sauropod dinosaurs were also found in the Lower Elliot Formation. These include Blikanasaurus, Euskelosaurus, Plateosaurus, etc.
Theropods such as Alwalkeria were also excavated in the Lower Elliot Formation.

Types of fossils found
Many different types of bones of the Eocursor were discovered in South Africa, making reconstruction of its physical appearance much simpler.

• Parts of the skull and teeth were discovered in 1993. The shape of the teeth was three-sided.
• Vertebrae of the neck (cervical) were also discovered.
• Extensive pieces of the shoulder and fore arm were found amongst the remains. These include left scapula, right humerus and parts of the radius. Bones of the manus such as carpals and metacarpals were also present in the fossils.
• Many bones of the hip joint such as the both ischia and right pubis are available.
• Most of the bones of the hind legs have been discovered. They include right femur, right tibia and a few metatarsal bones.

Butler, Smith and Norman
Richard J. Butler, Roger M. H. Smith, and David B. Norman were the paleontologists that classified and described the remains of the Eocursor.
R. J. Butler is a contemporary British paleontologist. He is currently associated with the University of Birmingham.
Roger Smith is a South African paleontologist who has worked comprehensively in the Karoo basin.
D. B. Norman is a British paleontologist who has worked on orinithiscian dinosaurs such as the Iguanadon. He is currently associated with the Cambridge University.

Physical characteristics
The Eocursor was a small dinosaur, weighing 20 to 25 kilos. It was about 2 to 3 feet in length.
It had a triangular head, short forelegs and a long tail. It had relatively big hands.
The tibial of the Eocursor was much longer than its femur. This modification indicates that it could run at high speeds, achieving acceleration within a few seconds.
It was an obligate biped.

Habits and habitat
The Eocursor had triangular teeth. These indicate that could have been carnivorous. But the size and other features of the dinosaur make it seem unlikely that it should have been solely carnivorous. Thus it was most probably an omnivore.
It had existed in southern Africa, so its habitat most likely consisted of forested areas.

Related species
The Eocursor is similar in appearance to Jurassic ornithischians such as the Lesothosaurus and the Scutellosaurus. It is considered lesser evolved than the Lesothosaurus, but more so than the Pisanosaurus.

Concluding notes
The discovery of the Eocursor has been ground breaking in the field of paleontology. The dinosaurs belonging to clade Orinithischia were very poorly understood until its discovery and their evolutionary path was even more of a mystery.
The Eocursor filled in many of the gaps in information that were confounding scientists about the habits ornithischians such as the Stegosaurus and the Iguanadon such as their herbivorous feeding habits.
As more facts about the Eocursor are gathered, the more information is made available about the higher evolved Jurassic dinosaurs.