why are there no terrestrial mammals in antarctica today
Wildlife of Antarctica There is relatively little diversity in Antarctica compared to much of the rest of the world. Terrestrial life is concentrated in areas near the coast. Flying birds nest on the milder shores of the Peninsula and the subantarctic islands. Eight species of penguins inhabit Antarctica and its offshore islands. They share these areas with seven pinniped species. The Southern Ocean around Antarctica is home to 10 cetaceans, many of them migratory. There are very few terrestrial invertebrates on the mainland, although the species that do live there have high population densities. High densities of invertebrates also live in the ocean, with Antarctic krill forming dense and widespread swarms during the summer. Benthic animal communities also exist around the continent.
Mammal Most mammals, including the six most species-rich orders, belong to the placental group. The three largest orders in numbers of species are Rodentia: mice, rats, porcupines, beavers, capybaras and other gnawing mammals; Chiroptera: bats; and Soricomorpha: shrews, moles and solenodons. The next three biggest orders, depending on the biological classification scheme used, are the Primates including the apes, monkeys and lemurs; the Cetartiodactyla including whales and even-toed ungulates; and the Carnivora which includes cats, dogs, weasels, bears, seals and allies.[3] According to Mammal Species of the World, 5,416 species were identified in 2006. These were grouped into 1,229 genera, 153 families and 29 orders.[3] In 2008, the International Union for Conservation of Nature (IUCN) completed a five-year Global Mammal Assessment for its IUCN Red List, which counted 5,488 species.[4] According to a research published in the Journal of Mammalogy in 2018, the number of recognized mammal species is 6,495 species included 96 recently extinct.[5]