Who is responsible for the ecological destruction of ancient Australia?
Beginning:
After the Intellectual Revolution, Homo sapiens gained the foresight to settle the outer world by acquiring technology and organizational skills. Before that only they lived in Afro-Asia land. Until the Intellectual Revolution, although they could leave their footprints on short-distance islands by swimming or rafting, they had not yet mastered the skills of crossing vast open oceans. Therefore, the Americas, Australia, Madagascar, New Zealand or the Hawaiian Islands were still beyond the reach of Homo sapiens.
But after the intellectual revolution, that picture changed. About 45,000 years ago, mankind set a milestone by colonizing Australia. The experts have to go to great lengths to elaborate on this success story of sapiens. Because sapiens had to cross many sea channels to get to Australia. Some of these channels were more than hundreds of kilometers wide. According to the most accepted information among scientists, the first seafaring society arose among the sapiens living in the Indonesian archipelago. Their maritime knowledge and skills made them long-distance fishermen, traders, or long-distance explorers. They were able to reach Australia by relying on that knowledge and skills. This bold step of Homo sapiens is written in golden letters in the history pages. Because not only did humans leave their familiar Afro-Asian ecology, but it was the first instance of a large mammal crossing thousands of waterways to set foot on Australian soil.
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| Homo sapiens colonized Australia about 45,000 years ago; Image Source: Sovereign Union |
After the first human footprints on the sandy beaches of Australia, people found a completely different ecosystem, which was completely new to them. As people move forward leaving the vast plains, they encounter all kinds of unknown creatures. Almost all the animals were marsupials like kangaroos, except for the birds that flew in the sky of this completely unknown continent and the reptiles that walked with their chests. Marsupials are animals that give birth to small, helpless and embryo-like young, and nurse the young in a pouch near their abdomen. Although marsupials have never been seen in Africa or Asia, Australia is dominated by them in terms of numbers.
At that time, kangaroos weighing up to 200 kilograms and measuring up to 2 meters in length were common in Australia. Marsupial lions ruled the continent, which were the largest predators of the time. All the silence of nature would be broken in an instant by the loud footsteps of a flock of birds twice the size of flightless ostriches. Diprotodon, a monstrous animal, roamed fearlessly in the forest. The average weight of each of them was close to two and a half tons. A dragon-like chameleon or a five-meter-long snake would move cautiously and silently behind the bushes.
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| Giant Diprotodon in artist's drawing; Image Source: Laurie Beirne |
Within a few thousand years of sapiens settling in Australia, almost all giant animals were listed as extinct. Australia was then inhabited by twenty-four species of animals weighing more than fifty kilograms, of which twenty-three became extinct. Numerous smaller species also disappeared from Australia in this vortex of extinction. The ecological shell of the Australian continent, built up over millions of years, was broken within a few hundred years. A completely new ecosystem developed by Homo sapiens. Some scholars, while exonerating their own species, place the blame on weather and climate. But homo sapiens are not innocent, they can be brought to justice on the basis of at least three strong evidences.
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| Hunting of large animals by humans; Image Source: Zdenek Burian |
First, although Australia experienced a climate change 45,000 years ago, it does not qualify as a significant catastrophe. Because the earth's climate is always changing. This planet Earth has undergone numerous cooling and warming processes since its creation till today. According to scientists, for the past ten million years, the Earth has seen an ice age every one million years on average. The last ice age started about 75,000 years ago and lasted until 15,000 years ago. The monstrous Diprotodon appeared on the Australian continent about 1.5 million years ago. They managed to sustain their existence on earth by crossing the thorny path of at least ten ice ages, including two peaks of cold intensity 70,000 and 20,000 years ago. But what exactly caused them to suddenly disappear from nature 45 thousand years ago? If only Diprotodon had become extinct as a large animal, it would have been dismissed as a mere 'natural accident'. But the Australian megafauna (animals weighing more than 1000 kg from the Australian continent) rode the chariot of extinction with the Diprotodons. Hard as it is to believe, they became extinct around the same time that Homo sapiens crossed the oceans and colonized the Australian continent.
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| Ice age; Image Source: Xiataptara/ArtStation |
Second, megafauna have become extinct due to climate change - even if we accept that for the sake of argument, there are aquatic organisms that are rife. Even though Danga tasted the black paw of extinction 45,000 years ago, there is no evidence of extinction of marine animals. Because, while on land Homo sapiens took on the form of iconic terror, near the water they were nothing but babies. At that time navigational skills were just beginning to develop.
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| Australian marsupials; Image Source: Tumblr |
Third, when humans colonize a new area, it alters the ecosystem and causes mass extinctions of most megafauna. Let's take Australia as an example as well as New Zealand. 45,000 years ago, the New Zealand ecosystem survived the shock of the so-called climate catastrophe. But after humans set foot on the island, many animals disappeared. The Maori, reputed to be the first occupants of New Zealand, sapiens, arrived there 800 years ago. It took only a few centuries for most of the local megafauna to go extinct, along with 60% of the birds. The question may come to mind, 45 thousand years ago mankind did not have such advanced technology or weapons. So how did they manage to wreak such havoc on the ecology through the use of stone age technology? These three equivalent explanations are given by analysts.
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| Biodiversity of Ancient Australia; Image Source: Griffith University |
First, the first victims of this genocide were large animals, whose reproductive processes are extremely slow. In addition to a limited number of litters, the interval between two consecutive pregnancies was also long. If Homo sapiens killed a Diprotodon every few months, then mathematically the death rate would exceed the birth rate. Vishal-Bapu Hunting this Diprotodon and Megaphone was not a difficult task for the Stone Age man. They did not really fear any attack from Homo sapiens, two feet smaller than themselves. At first glance, humans did not appear to be dangerous animals. Because Homo sapiens didn't have huge muscular bodies, sharp teeth, or fast paws. So, when Diprotodon and Megaphon first appeared on Earth, they may have considered humans to be mere ape-like creatures. Maybe they just glanced at the people and decided to chew the grass again. But before they understood this destructive attitude of mankind, they had to leave the earth forever.
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| Australian Megafauna; Image Source: Peter Trussler/Monash University |
According to the second explanation, by the time humans set foot in Australia, they had already mastered the use of fire. They used to set fire to the impenetrable and dense forests to convert them into grasslands. Because the open grasslands were ideal places for hunting. Some vegetable crops testify in favor of this interpretation, proving that they are more mature. For example, 45,000 years ago, eucalyptus plants were rare in Australia. The arrival of Homo sapiens led to a rapid increase in the number of Eucalyptus plants in Australia. Because, while other trees and shrubs were wiped out by forest fires, eucalyptus was able to spread far and wide due to its resistance to fire. While koalas that depended on eucalyptus trees survived, other species that depended on trees and shrubs disappeared. Animals faced a terrible disaster as the food chain collapsed.
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| Eucalyptus; Image Source: Needpix |
The third interpretation, however, gave some relief to people from standing in the judgment seat. While hunting and fire care play a large role in mass extinctions, climate change cannot be completely ignored. Climate change in Australia 45,000 years ago pushed the ecosystem there towards imbalance and instability. Although previously able to cope with the shocks of climate change alone, climate change and the presence of Homo sapiens - the presence of two regulators - hit the giant animals from different directions.
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| Skeleton of Thylacolio in Naracorte Cave; Image Source: Wikimedia Commons. |
But more evidence is needed. It cannot be concluded that any of these three actually happened until detailed evidence is obtained. However, most researchers and scientists believe that if Homo sapiens had not settled in Australia, the continent of Australia would still be home to Diprotodon, Megaphon, marsupial lion or giant kangaroo.