Charismatic Megafauna
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KIDS CORNER CHARISMATIC MEGAFAUNA This document aims to teach you about megafauna. This presentation has the following structure: Slide 1 - What Are Megafauna? Slide 2 - Charismatic Megafauna Slide 3 - Megafauna Extinction Theories Slide 4 - Timeline Slide 5 - Living Megafauna Slide 6 - Extinct Australian Megafauna Slide 7 - Extinct African Megafauna Slide 8 - Case Study: Diprotodon optatum Slide 9 - Australian Curriculum Mapping KIDS CORNER CHARISMATIC MEGAFAUNA What Are Megafauna? Combining the Latin words for “large” (mega) and “animals” (fauna) creates the word “megafauna.” Megafauna are the largest animals on Earth – the ones that dominate the landscape during the time in which they live. Dinosaurs were certainly the megafauna of their time. And after the dinosaurs all died off in the mass extinction at the end of the Cretaceous period, new megafauna arose. They looked a lot like their modern descendants but were much bigger. Imagine wombats the size of a compact car, birds that stood taller than a human being, or snakes that make modern pythons look puny. Scientists consider animals that weigh more than 44 kilograms as adults to be megafauna. The term applies not only to mammals, but also to birds, reptiles, and amphibians—in short, all vertebrates, or animals with a backbone. By that definition, there are plenty of megafauna walking the Earth and swimming in its oceans today. Gorillas, elephants, and whales are prime examples. KIDS CORNER CHARISMATIC MEGAFAUNA Charismatic Megafauna The word “charismatic” means “charming” or “fascinating.” Conservationists coined the term “charismatic megafauna” during the 1980s to acknowledge that people find large animals very interesting, especially large animals that exhibit endearing or intriguing behaviour. Charismatic megafauna are essentially charming or fascinating large animals. The idea was that focusing attention on the plight of these large animals - many of them endangered - would benefit all species faced with the possibility of extinction. If people visited zoos and wildlife sanctuaries to see these large, fascinating animals, they would learn about other animals as well and become interested in helping prevent their extinction. They might even become true conservationists. Because of the leading role conservationists thought charismatic megafauna could play in saving other species, they have also been referred to as “flagship” species. Giant pandas are a prime example of a modern charismatic megafauna species. Zoos around the world have seen attendance soar after opening a giant panda exhibit, and the birth of a panda cub is typically celebrated and publicised. KIDS CORNER CHARISMATIC MEGAFAUNA Megafauna Extinction Theories For roughly two million years, large mammals, many of them the distant ancestors of today’s large mammals, lived throughout the world. They coexisted with human beings long enough for evidence of them to exist in Stone Age cave paintings. Toward the end of the Pleistocene period, these megafauna species disappeared, but scientists are still debating the likely causes. Some scientists have suggested that the disappearance of woolly mammoths, sabre-tooth tigers, and other large mammals can be blamed on over-hunting by humans. Some have theorised that they were wiped out by disease, or by a meteorite impact. A common theory today is that climate change altered their habitats faster than the megafauna could adapt. At the time that megafauna species were dying off, the Earth was transitioning from the cool, dry climate that existed at the end of the last ice age to the warmer, wetter climate we know today. Many scientists now believe that several factors contributed to the extinction of the Pleistocene megafauna. However, there’s no single theory that explains what all of those factors are and how they interacted to cause the extinction of the large mammals of the period. KIDS CORNER CHARISMATIC MEGAFAUNA Timeline Megafauna appeared in the Pleistocene epoch, which began about 2.6 million years ago, toward the end of the Cenozoic era. Their populations peaked a little more than 40,000 years ago. Megafauna species began to die off roughly 30,000 years ago, and the last of the Pleistocene megafauna became extinct about 5,000 years ago. In Australia, the Diprotodon optatum (pictured bottom right), a megafauna species, was believed to have roamed the Liverpool Plains of New South Wales as recently as 7,000 years ago. The megafauna extinctions occurred at different times in different parts of the world. It’s likely that the combination of factors leading to extinction also differed from one geographic region to the next. KIDS CORNER CHARISMATIC MEGAFAUNA Living Megafauna A number of species living today fit the definition of megafauna as animals weighing more than 44 kg as adults. Australia’s largest living terrestrial mammal is the red kangaroo, which weighs as much as 85 kg in adulthood. That’s a far cry from the extinct diprotodon, which weighed up to 2,786 kg and was the largest marsupial in history. Elephants are the largest land mammals living today, and rhinoceroses are the second largest. The gorilla is the largest living primate, weighing up to 266 kg. South America’s capybara, weighing up to 65 kg, is the largest living rodent. Giraffes are the tallest land mammals, reaching heights of 6 m, and the heaviest one studied weighed in at 1,930 kg. The ostrich is the largest living bird, and the saltwater crocodile is the largest reptile. The oceans are also home to modern megafauna. The blue whale is not only the largest whale but also the largest animal that has ever lived. It can reach 30 meters in length and weighs 170 tonnes or more. Other modern marine megafauna include the killer whale, which is the largest modern dolphin species, the leatherback turtle, which weighs up to 900 kg, and the rarely seen giant squid, which reaches lengths of up to 12 meters. KIDS CORNER CHARISMATIC MEGAFAUNA Extinct Australian Megafauna • Australia lost 88% of its megafauna during the late Pleistocene extinctions; • The giant short-faced kangaroo was the largest kangaroo ever known to exist. At 2 metres in height, it weighed about three times as much as today’s red kangaroo; • Despite its name, the top predator in Pleistocene Australia was not a member of the cat family, but a marsupial known as the marsupial lion. About 1 metre long, it had long pointed incisors for taking down large prey; • Nicknamed the “Demon Duck of Doom,” bullockornis planei was a 2.5 metre tall bird that looked somewhat like an ostrich or emu but was related to ducks and geese; • Megalania was the largest lizard that ever existed. It was at least 5.5 metres long and had a mouthful of lethal curved teeth; • Meiolania was a 2.5 metre horned tortoise with a spiked tail. • The Tasmanian tiger, a marsupial, was not declared totally extinct until 1936. Despite numerous reports of its existence, there has been no irrefutable evidence of its survival; • The diprotodon, which we will look at more closely in a case study, was the largest marsupial that ever existed. It weighed approximately 2 tonnes, resembled a rhinoceros and was distantly related to the modern wombat. KIDS CORNER CHARISMATIC MEGAFAUNA Extinct African Megafauna Far more megafauna survived the Pleistocene in Africa than in other parts of the world. That’s why Africa has so many living megafauna today. More of the larger African megafauna species (between 1,000 and 10,000 kg) became extinct than smaller megafauna. Among the 20% of Africa’s megafauna that are now extinct are: • Deinotherium was an enormous, distant relative of elephants, weighing about three times as much as a modern elephant and nearly as tall as modern giraffes. Their specially shaped tusks enabled them to uproot trees and strip their bark. • Dinofelis was a sabre-toothed big cat. It was a ferocious ambush predator, thanks in part to its ability to climb trees with ease and leap down onto the backs of prey animals. • Sivatherium, known as Shiva’s Beast, was a giraffid that was once common in North Africa. About 2.2m tall, it had multiple horns and was depicted in rock paintings created approximately 7,000 years ago. KIDS CORNER CHARISMATIC MEGAFAUNA Case Study: Diprotodon Optatum The diprotodon weighed approximately two tonnes and was the Earth’s largest marsupial ever. At 4m in length and up to 2,800 kg in weight (females were somewhat smaller), it has some physical similarities to modern rhinos and elephants, but its closest relative is the modern wombat. Diprotodon gets its name from its two front-facing lower incisors. (In Greek, “di” means “twice,” “proto” means “first,” and “odon” means “tooth.”) The diprotodon used its powerful, clawed feet to dig up the plants and roots that were its diet. Like the elephant, the diprotodon is thought to have been a social animal that lived in small family groups. There is some evidence to suggest that it was preyed upon by marsupial lions. Diprotodon inhabited Australia before the arrival of the first indigenous people approximately 50,000 years ago and co-existed with them for thousands of years. It lived primarily in semi-arid plains, savannahs and open woodlands. It became extinct approximately 25,000 years ago. Though spear marks have been found on the bones of one specimen, the fact that humans and diprotodons coexisted for so long makes it unlikely that humans caused their extinction through overkilling. Scientists believe it is more likely that climate and habitat changes caused the extinction of the diprotodon. KIDS CORNER CHARISMATIC MEGAFAUNA Australian Curriculum Mapping GRADE 5 SCIENCE (ACSSU043): Living things have structural features and adaptations that help them to survive in their environment. GRADE 6 SCIENCE (ACSSU094): The growth and survival of living things are affected by the physical conditions of their environment.