Scientists think they had discovered exactly when kangaroos started to hop. Researchers from Sweden have used fossils to discover the secrets of Australia's most famous mammal.
The team cracked the mystery of the hopping animal, by examing evidence of 20-million-year-old kangaroo relative. The researchers from the Swedish Natural History Museum and Uppsala University used fossils found in northwest Queensland, Australia in their research.
The question of when the hop began puzzles experts
The question of when kangaroos started hopping has been on the mind of scientists for some time. No fossils of kangaroos older than 2 million years old exist which made tracing the kangaroo's evolution from walking or climbing animal to a hopping one very difficult.
Previous research had suggested that the hopping was actually an adaptation to climate change. Australia used to be covered in denser, wetter forests.
When they began to change into more open grassland, it has been hypothesized that the kangaroos too changed their behavior and started to hop through the long grass then stand tall and observe similarly to prairie dogs do. The latest research from Sweden shows that kangaroos were likely to be hopping well before grasslands became common in Australia.
20 million-year-old fossil unlocks the answer
To come up with the theory, the Swedish team examined fossils of an ancient mammal called balbarids. Recently an almost complete balbarid skeleton was unearthed providing the opportunity to understand this distance kangaroo relative in more depth.
To learn more about the animal's life and locomotion, the scientists built a digital model of the animal using the knowledge they could glean from its legs and ankle shapes. The model revealed that some balbarids were definitely walkers, other climbers and some were definitely hoppers.
From this knowledge, the scientists can now assume that if these animals were already hopping 20 million years ago, then it is very likely that kangaroos were hooping at that time too. Kangaroos are found in every state and territory in Australia although the species and density of the population change dramatically as you move around the country.
Kangaroo is an icon of Australia
The kangaroo is synonymous with Australia and can be seen on its coat of arms and some of its coins. Interestingly Australia is one of the few nations to eat the animals featured on its national coat of arms.
Kangaroo meat is a common source of meat in Australia. Although the killing of kangaroo meat has been controversial in the past due to questions about sustainability, the meat is very low in fat compared to other traditional forms of edible meat.
The Swedish research group has published their findings, titled, Climbing adaptations, locomotory disparity, and ecological convergence in ancient stem 'kangaroos', in the Royal Society Open Science Journal.