Teacher Steve, I had to look the following up (hint):
'anthropocene', the current geological age, viewed as the period during which human activity has been the dominant influence on climate and the environment.
'The absolute numbers of all extinct animal and plant species have so far been comparably low. In the last 500 years, just 1-2 per…
Teacher Steve, I had to look the following up (hint):
'anthropocene', the current geological age, viewed as the period during which human activity has been the dominant influence on climate and the environment.
'The absolute numbers of all extinct animal and plant species have so far been comparably low. In the last 500 years, just 1-2 percent of all species have disappeared, and this value refers to the 1.9 million known species.'
'Even today, new species are being discovered almost every day somewhere in the world. Estimates of the actual number of species range from 3.6 million to well over 100 million. 1-2 percent loss of known species appears to be rather small compared to 75-96 percent loss in the previous five mass extinctions.'
IT'S THE EXTINCTION RATE – AND IT'S DRAMATIC
But is it that easy? Is it possible to compare the historical mass extinctions with the ongoing and expected losses in the Anthropocene? As for the role of human beings, another value is crucial: the rate of disappearance of species, that is the extinction rate.
According to the International Union for the Conservation of Nature (IUCN):
"THE RATE OF EXTINCTION IS CURRENTLY 1,000 TO 10,000 TIMES THE VALUE OF THE NORMAL RATE OF EXTINCTION."
'The normal value is the rate that would occur without the influence of man. Usually, up to five species a year a being lost forever. Currently, a dozen species disappear from our planet – every day!'
'According to recent studies by Dr Gerardo Ceballos from the Universidad Nacional Autonoma de Mexico, the situation is dramatic'.
"UP TO 50 PERCENT OF ALL INDIVIDUAL ANIMALS, BOTH ENDANGERED AND NOT ENDANGERED WERE LOST OVER THE PAST DECADES."
'Ceballos claims that a third of all species currently losing population are not listed as endangered – a „biological annihilation“.
'Whether or not the sixth mass extinction is already underway or about to start, it is clearly man-made, scientists agree, therefore claiming the dawn of the Anthropocene.'
'BIOLOGICAL DIVERSITY IS KEY TO OUR EXISTENCE – AND ECONOMIC ASSET AS WELL
The massive extinction of species is undermining the biological diversity and, thus the fundament of life on our planet, including us, humans. If we don't want to destroy what has been evolved over billions of years on earth and be responsible for what we created the term genocide, we need to act without further hesitance.'
'The task is difficult as it relies on a complex set of measures which concern our economy, our social behaviour and ethics - on both, global and local scale. It is a race against extinction facing the dilemma between our current understanding of economic development and preserving nature and species.' Links below.
Hi Fern! There is debate about just when the Holocene ended and the Anthropocene began (the Holocene, a period marked by climate stability, began ~11,600 ybp). Some say when agriculture began, some say at the start of the industrial revolution, some say when industrialization really took off ~1945. The upshot is this: we now have CO2 levels present in the atmosphere not seen for the last 800,000 years. The rate of CO2 rise is unprecedented in geologic history. Up to now, human caused extinctions have mainly been via habitat degradation, habitat loss, or over hunting. Soon, very rapid warming may take over as the main cause of extinction. That human civilization emerged during the climatically stable Holocene is no accident. The Anthropocene will not have such climatic stability, I fear. If you want an informative, entertaining background to the geo-science behind some of this, start with 'Prehistoric Road Trip', a 3 part series on PBS.
Teacher Steve, I had to look the following up (hint):
'anthropocene', the current geological age, viewed as the period during which human activity has been the dominant influence on climate and the environment.
'The absolute numbers of all extinct animal and plant species have so far been comparably low. In the last 500 years, just 1-2 percent of all species have disappeared, and this value refers to the 1.9 million known species.'
'Even today, new species are being discovered almost every day somewhere in the world. Estimates of the actual number of species range from 3.6 million to well over 100 million. 1-2 percent loss of known species appears to be rather small compared to 75-96 percent loss in the previous five mass extinctions.'
IT'S THE EXTINCTION RATE – AND IT'S DRAMATIC
But is it that easy? Is it possible to compare the historical mass extinctions with the ongoing and expected losses in the Anthropocene? As for the role of human beings, another value is crucial: the rate of disappearance of species, that is the extinction rate.
According to the International Union for the Conservation of Nature (IUCN):
"THE RATE OF EXTINCTION IS CURRENTLY 1,000 TO 10,000 TIMES THE VALUE OF THE NORMAL RATE OF EXTINCTION."
'The normal value is the rate that would occur without the influence of man. Usually, up to five species a year a being lost forever. Currently, a dozen species disappear from our planet – every day!'
'According to recent studies by Dr Gerardo Ceballos from the Universidad Nacional Autonoma de Mexico, the situation is dramatic'.
"UP TO 50 PERCENT OF ALL INDIVIDUAL ANIMALS, BOTH ENDANGERED AND NOT ENDANGERED WERE LOST OVER THE PAST DECADES."
'Ceballos claims that a third of all species currently losing population are not listed as endangered – a „biological annihilation“.
'Whether or not the sixth mass extinction is already underway or about to start, it is clearly man-made, scientists agree, therefore claiming the dawn of the Anthropocene.'
'BIOLOGICAL DIVERSITY IS KEY TO OUR EXISTENCE – AND ECONOMIC ASSET AS WELL
The massive extinction of species is undermining the biological diversity and, thus the fundament of life on our planet, including us, humans. If we don't want to destroy what has been evolved over billions of years on earth and be responsible for what we created the term genocide, we need to act without further hesitance.'
'The task is difficult as it relies on a complex set of measures which concern our economy, our social behaviour and ethics - on both, global and local scale. It is a race against extinction facing the dilemma between our current understanding of economic development and preserving nature and species.' Links below.
https://www.amnh.org/shelf-life/six-extinctions
https://www.nationalgeographic.org/lesson/sixth-mass-extinction/#:~:text=The%20Anthropocene%20Epoch%2C%20or%20the,%2C%20perhaps%2C%20even%20our%20own.
Hi Fern! There is debate about just when the Holocene ended and the Anthropocene began (the Holocene, a period marked by climate stability, began ~11,600 ybp). Some say when agriculture began, some say at the start of the industrial revolution, some say when industrialization really took off ~1945. The upshot is this: we now have CO2 levels present in the atmosphere not seen for the last 800,000 years. The rate of CO2 rise is unprecedented in geologic history. Up to now, human caused extinctions have mainly been via habitat degradation, habitat loss, or over hunting. Soon, very rapid warming may take over as the main cause of extinction. That human civilization emerged during the climatically stable Holocene is no accident. The Anthropocene will not have such climatic stability, I fear. If you want an informative, entertaining background to the geo-science behind some of this, start with 'Prehistoric Road Trip', a 3 part series on PBS.
So glad to have prompted you out and through the CO2 to serve up some more. Thank you Steve, I fill my cup. A hug and Salud!
Great recommendation re "Prehistoric Road Trip". Anyone who is a PBS member can watch the episodes on their own time: https://www.pbs.org/show/prehistoric-road-trip/