filmov
tv
Earth is Currently Experiencing 6th Mass Extinction
Показать описание
The planet’s sixth mass extinction is underway, courtesy humans. Report after report has attested to this fact. This marks the beginning of the Anthropocene Epoch.
As we enter 2023, many more species are expected to go extinct as a result of human activities. In what year will the human population grow too large for the Earth to sustain? The answer is about 1970, according to research by the World Wildlife Fund. In 1970, the planet's 3 and a half billion people were sustainable. But now, the population is 8 billion. Today, wild plants and animals are running out of places to live. The scientists you're about to meet say the Earth is suffering a crisis of mass extinction on a scale unseen since the dinosaurs. Human activity is killing nature at an unprecedented rate. We are now experiencing the consequences in the form of a possible sixth mass extinction.
What is a mass extinction?
Extinction is a part of life, and animals and plants disappear all the time. About 98% of all the organisms that have ever existed on our planet are now extinct.
When a species goes extinct, its role in the ecosystem is usually filled by new species, or other existing ones. Earth's 'normal' extinction rate is often thought to be somewhere between 0.1 and 1 species per 10,000 species per 100 years. This is known as the background rate of extinction.
A mass extinction event is when species vanish much faster than they are replaced. This is usually defined as about 75% of the world's species being lost in a short period of geological time - less than 2.8 million years.
How many mass extinctions have there been?
In the last 500 million years, five great mass extinction events have changed the face of life on Earth. We know what caused some of them, but others remain a mystery.
The Ordovician-Silurian mass extinction occurred 443 million years ago and wiped out approximately 85% of all species. Scientists think it was caused by temperatures plummeting and huge glaciers forming, which caused sea levels to drop dramatically. This was followed by a period of rapid warming. Many small marine species died out.
The Devonian mass extinction event took place 374 million years ago and killed about three-quarters of the world's species, most of which were marine invertebrates that lived at the bottom of the sea. This was a period of many environmental changes, including global warming and cooling, a rise and fall of sea levels and a reduction in oxygen and carbon dioxide in the atmosphere. We don't know exactly what triggered the extinction event.
The Permian mass extinction, which happened 250 million years ago, was the largest and most devastating event of the five. The Permian-Triassic extinction event is also known as the Great Dying. It eradicated more than 95% of all species, including most of the vertebrates which had begun to evolve by this time. Some scientists think Earth was hit by a large asteroid which filled the air with dust particles that blocked out the Sun and caused acid rain. Others think there was a large volcanic explosion which increased carbon dioxide and made the oceans toxic.
As we enter 2023, many more species are expected to go extinct as a result of human activities. In what year will the human population grow too large for the Earth to sustain? The answer is about 1970, according to research by the World Wildlife Fund. In 1970, the planet's 3 and a half billion people were sustainable. But now, the population is 8 billion. Today, wild plants and animals are running out of places to live. The scientists you're about to meet say the Earth is suffering a crisis of mass extinction on a scale unseen since the dinosaurs. Human activity is killing nature at an unprecedented rate. We are now experiencing the consequences in the form of a possible sixth mass extinction.
What is a mass extinction?
Extinction is a part of life, and animals and plants disappear all the time. About 98% of all the organisms that have ever existed on our planet are now extinct.
When a species goes extinct, its role in the ecosystem is usually filled by new species, or other existing ones. Earth's 'normal' extinction rate is often thought to be somewhere between 0.1 and 1 species per 10,000 species per 100 years. This is known as the background rate of extinction.
A mass extinction event is when species vanish much faster than they are replaced. This is usually defined as about 75% of the world's species being lost in a short period of geological time - less than 2.8 million years.
How many mass extinctions have there been?
In the last 500 million years, five great mass extinction events have changed the face of life on Earth. We know what caused some of them, but others remain a mystery.
The Ordovician-Silurian mass extinction occurred 443 million years ago and wiped out approximately 85% of all species. Scientists think it was caused by temperatures plummeting and huge glaciers forming, which caused sea levels to drop dramatically. This was followed by a period of rapid warming. Many small marine species died out.
The Devonian mass extinction event took place 374 million years ago and killed about three-quarters of the world's species, most of which were marine invertebrates that lived at the bottom of the sea. This was a period of many environmental changes, including global warming and cooling, a rise and fall of sea levels and a reduction in oxygen and carbon dioxide in the atmosphere. We don't know exactly what triggered the extinction event.
The Permian mass extinction, which happened 250 million years ago, was the largest and most devastating event of the five. The Permian-Triassic extinction event is also known as the Great Dying. It eradicated more than 95% of all species, including most of the vertebrates which had begun to evolve by this time. Some scientists think Earth was hit by a large asteroid which filled the air with dust particles that blocked out the Sun and caused acid rain. Others think there was a large volcanic explosion which increased carbon dioxide and made the oceans toxic.
Комментарии