Thylacoleo hilli facts for kids

Thylacoleo hilli was an ancient animal that lived during the Pliocene epoch. This was a long time ago, between 5.3 and 2.6 million years ago. It was a type of "marsupial lion," but much smaller than its famous cousin, Thylacoleo carnifex. In fact, Thylacoleo hilli was only about half the size of another species, Thylacoleo crassidentatus.

Scientists found the first main fossil, called a holotype, in Town Cave in South Australia. Other possible fossils were also found at the Bow fossil site. Students and staff from the University of New South Wales discovered these in 1979.

Discovering Thylacoleo hilli

A scientist named Neville Pledge first described Thylacoleo hilli. He published his findings in 1977 in a museum record. The most important fossil found was a single tooth. This tooth was a third premolar.

It was found in a cave near Curramulka in South Australia. The tooth showed that the animal was a meat-eater, like other marsupial lions. It was also about half the size of the well-known Thylacoleo carnifex.

A cave explorer named Alan Hill found this tooth in 1956. He was exploring a place called "Town Cave." The species was named hilli to honor him for finding the first fossil.

About This Ancient Marsupial Lion

Thylacoleo hilli is the smallest and oldest known species of the Thylacoleo group. This group of three species is often called "marsupial lions." They got this name because they looked and acted a bit like African lions. However, they are only distantly related to the modern Thylacinus cynocephalus, also known as the Tasmanian tiger.

These animals are the earliest known marsupial lions. They appeared during the Pliocene epoch. They lived at the same time as the larger Thylacoleo crassidentatus.

We don't have many fossils of T. hilli. Most of what we know comes from a few broken pieces. This is different from Thylacoleo carnifex, which has many well-preserved fossils. Scientists checked if the small tooth found might have been a baby tooth. But they found signs of wear, meaning it was a permanent tooth.

Where Thylacoleo hilli Lived

The main tooth studied by Pledge was found in a cave. This cave was a vertical shaft in limestone rocks. It was located on the Yorke Peninsula in South Australia. This happened in 1956.

The cave had been dug up before to get water for the local area. Earlier explorations had also found fossils of other large animals. These included a diprotodont and a skeleton of another marsupial lion, Thylacoleo carnifex.

The tooth's age suggests it was deposited during the Pliocene period or even earlier. Other fossil pieces were found in New South Wales. These were at the Bow River site. These fossils also date back to the early Pliocene.

A small piece of an incisor tooth was found near the Town Cave site. It was too worn to identify exactly. But its size suggested it also belonged to Thylacoleo hilli. This was based on comparing it to the better-known T. carnifex.

Thylacoleo hilli was about the same size as another ancient meat-eating marsupial. This was Wakaleo alcootaensis. It's possible that Thylacoleo hilli lived in places where Wakaleo alcootaensis did not.