The question of how many species of kangaroos exist is complex because the common term “kangaroo” is used loosely to describe several groups of Australian marsupials. These iconic animals belong to the family Macropodidae, which translates to “large foot.” This family includes large terrestrial kangaroos, wallabies, wallaroos, pademelons, and tree-kangaroos. A precise count depends on how broadly the term is defined and requires navigating the scientific classification.
Taxonomy and the Official Species Count
The family Macropodidae is a diverse group of marsupials native to Australia and New Guinea, containing approximately 63 recognized living species. This total includes large kangaroos, wallabies, pademelons, and tree-kangaroos. The classification is dynamic, and the exact species count can shift due to ongoing genetic research.
Historically, the traditional definition of the “Great Kangaroos” encompassed the genus Macropus, which included up to 14 species. A significant reassessment in 2019 split this broad group based on phylogenetic evidence. Under current scientific classification, Macropus now contains only two extant species: the Eastern Grey Kangaroo and the Western Grey Kangaroo. Species formerly grouped with them, such as the Red Kangaroo and the various Wallaroos, have been moved into different genera, like Osphranter.
Specialized Adaptations of Major Groups
Macropod species have evolved distinct biological traits to fill specific ecological niches, explaining their wide variation in size and form. The largest terrestrial species, like the Red Kangaroo, display impressive adaptations for survival in Australia’s arid interior. Their powerful hind legs utilize the Achilles tendon like a spring, making their hopping locomotion incredibly energy-efficient for covering vast distances. The Red Kangaroo also possesses specialized physiological mechanisms, such as concentrated urine and the reabsorption of water in the intestine, to minimize water loss.
Tree Kangaroos
In sharp contrast to terrestrial hoppers, Tree Kangaroos (Dendrolagus) have returned to an arboreal lifestyle. Their limbs have adapted significantly, featuring shorter hind legs and longer, muscular forelimbs for grasping and climbing. Their hind limbs can move independently, unlike the synchronized motion of ground-dwelling relatives, allowing them to maneuver in the canopy.
Rock Wallabies
Rock Wallabies (Petrogale) exhibit specialized features for navigating steep, rocky outcrops and cliff faces. These species possess unique, ridged pads on the soles of their hind feet, providing exceptional traction on slick surfaces. Their muscular tails are used as a flexible counterbalance during acrobatic leaps across boulders. Many rock wallaby species also display serial tooth replacement, where molars move forward in the jaw and are replaced from the rear as older ones are worn down by abrasive vegetation.
Distribution and Conservation Status
The Macropodidae family’s geographic range extends beyond mainland Australia to include New Guinea and surrounding islands. While the large, well-known kangaroos are widespread and stable across Australia, many smaller, specialized macropods are restricted to specific regions. New Guinea is home to numerous species not found on the mainland, including the Dorcopsis and Dorcopsulus genera (forest wallabies) and most of the 14 species of Tree Kangaroos.
The conservation status of macropods varies dramatically, reflecting the impact of introduced predators and habitat loss. The Red Kangaroo and the two Grey Kangaroo species are abundant and listed as “Least Concern,” often requiring population management. Conversely, many smaller, habitat-specific species face significant threats.
The Brush-tailed Rock-wallaby is listed as “Vulnerable” due to predation by feral foxes and cats, as well as competition from introduced herbivores. Most New Guinean Tree Kangaroo species, such as Matschie’s Tree Kangaroo, are considered “Endangered” or “Vulnerable.” This is primarily due to habitat destruction from logging and mining, compounded by unsustainable hunting practices. The conservation challenges for the family are centered on protecting these specialized, geographically restricted populations.