Prehistoric Animals: Meet Murrayglossus, Egg-Laying Mammal as Big as a Sheep

The murrayglossus, an egg-laying mammal that is as big as a sheep, is one of the many prehistoric animals that closely resemble their modern-day descendants.

The majority of prehistoric animals have gone into extinction, though some, like horseshoe crabs, are still around. The primary source of information that scientists use to understand ancient animals is fossil evidence. For instance, the Murrayglossus hacketti, an Australian egg-laying mammal that was once common but is now extinct.

Australia was once home to enormous creatures like the diprotodon, meiolania, and megalania. A type of echidna, Murrayglossus hacketti was a large mammal about the size of a sheep. Although smaller in size than their ancestors, echidnas of the present day have provided valuable insights into the study of extinct species that once inhabited Australia.

The Murrayglossus

Murrayglossus is a genus that belongs to the Tachyglossidae family and includes the echidna, which is one of the two extant members of this family along with the Zaglossus. As a member of the Monotremata order, they are closely related to the platypus. Murrayglossus hacketti, also known as Hackett's giant echidna, is the only known species of this genus, and its fossils have been found in Western Australia, dating back to the Pleistocene period.

With a length of approximately 3.3 feet and a weight of 66 pounds, Murrayglossus hacketti had straight legs that helped them move through dense woodland habitats. They had spikes covering their bodies and a long beak similar to that of modern long-beaked echidnas. New fossil discoveries of this species can provide further insight into its appearance and lifestyle.

Murrayglossus Fossils

In 1909, the first fossils of Hackett's giant echidna were discovered in Mammoth Cave, located in Western Australia. The cave's fossils date back to the Pleistocene period, and other excavations in the area have uncovered remains of animals such as Zygmatrurus and various shark species.

The first Murrayglossus fossils were excavated alongside specimens of Sthenurus and Macropus fossils. In 1914, Ludwig Glauert described Murrayglossus as a new genus, named in honor of John Winthrop Hackett, a newspaper editor, politician, and supporter of the exploration expeditions that led to the discovery of these fossils.

During the excavation, only a few vertebrae and leg bones were found, while cranial material was completely absent. Initially, the species was classified under the Zaglossus genus, but in 2022, a study published in the journal Alcheringa: An Australasian Journal of Palaeontology suggested that echidnas may have migrated from the Bird's Head Peninsula on the island of New Guinea to Australia at the beginning of the last ice age, about 2.6 million years ago. The study also resulted in the creation of the Murrayglossus genus.

According to Animalia, Murrayglossus hacketti is the largest known monotreme to have ever existed. The genus name combines the surname of the paleontologist Peter Murray, who dedicated decades studying echidna and "glossus," the Greek word for "tongue."

Diet and Extinction

The Hackett's giant echidna, like its modern-day relatives, probably had a diet consisting of small invertebrate insects. While short-beaked echidnas mainly consume ants and termites, long-beaked echidnas feed on earthworms. As an insectivore, the Hackett's giant echidna likely inhabited dense woodland habitats and had to consume a large number of insects to support its size.

Murrayglossus hacketti lived during the Pleistocene period, and the timing of its extinction is still uncertain. This period was characterized by the presence of megafauna and early humans in Australia. Evidence of hunting, such as burn marks and chippings on fossils, suggests that humans may have hunted this giant echidna, which may have also suffered from habitat loss. Australia's significant environmental changes were likely a contributing factor to the loss of its megafauna, AZ Animals reports.