Environmental degradation by human activity is one of the main causes of biodiversity loss.

D.Bressan

In Earth’s long history estimated 99% of all species ever living here went extinct. Extinction is part of life’s history and extinction of single species happens all the time. Over time lost species are eventually replaced as natural selection acts on the survivors and new species evolve. Mass extinctions are defined by the loss of a large part of the biodiversity in a (geologically speaking) short span of time, when the evolution of new species can’t compensate the losses. This can be seen also in the geological record.

Five big mass extinction events are recognized by paleontologists. At the end of the Ordovician some 443 million years ago, when an estimated 86% of all marine species disappeared. At the end of the Devonian some 360 million years ago, when 75% of all species disappearance. At the end of the Permian some 250 million years ago, the worst extinction event so far with 96% of all known species lost. At the end of the Triassic some 201 million years ago, when 80% of all species disappeared. The most famous mass extinction happened at the end of the Cretaceous some 65 million years ago, when 76% of all species went extinct, including the large dinosaurs and ammonites. Minor extinction events also happened, like the extinction of the Pleistocene megafauna at the end of the ice-age some 10,000 years ago.

Scientist long debated and still debate about the factors driving mass extinction. Factors contributing to the disappearance of a species can be geological catastrophes, like volcanism, impacts or climate change, but also biological factors, like competition, diseases or depletion of resources. The most likely explanation for the most recent mass extinction at the end of the Cretaceous, is the impact of a large asteroid, disrupting the ecosystems on a global scale. For the extinction of many large mammal species at the end of the last ice-age among climate change also the spread of hunter-gatherer societies may played a role.

In the last 400 years, a large number of mammal, bird, amphibian and reptile species went extinct. Especially species with a limited range, living for example only on islands, quickly disappeared after humans arrived there, hunting the small populations or destroying their natural habitat. Research published some years ago compared the recent extinction rate with the reconstructed rates during geologically quiet times and mass extinctions. At the time, the study confirmed that current extinction rates are higher than would be expected from the fossil record, approaching a mass extinction. Nowadays human activity is impacting the environment on a global scale and on an ever-accelerating rate.

According to a summary report from the United Nations, one in four known species are at risk of extinction. Amphibians are among the most vulnerable with 40% of the studied species at risk, followed by conifers with 34%, reef corals with 33%, cartilaginous fish like sharks and rays with 31%, mammals with 25% and birds with 14%. Among invertebrates, 27% of the studied crustaceans are at risk. Recent surveys have also shown a dramatic collapse in insect populations.

According to the report, only a quarter of Earth’s surface is substantively free of the impacts of human activities, especially in high latitudes, an area that will continue to shrink in the next decades. Habitat loss is a major threat to biodiversity, followed by over-exploitation of animal populations, the spread of invasive species and diseases by humans, pollution and climate change.

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Environmental deterioration by human activity is among the primary reasons for biodiversity loss.

D.Bressan

In Earth’s long history approximated(**************************************** )% of all types ever living here went extinct. Termination becomes part of life’s history and termination of single types occurs all the time. In time lost types are ultimately changed as natural choice acts upon the survivors and brand-new types progress. Mass terminations are specified by the loss of a big part of the biodiversity in a (geologically speaking) brief period of time, when the development of brand-new types can’t compensate the losses. This can be seen likewise in the geological record.

5 huge mass termination occasions are acknowledged by paleontologists. At the end of the Ordovician some 443 million years earlier, when an approximated 86% of all marine types vanished. At the end of the Devonian some 360 million years earlier, when 75% of all types disappearance. At the end of the Permian some 250 million years earlier, the worst termination occasion up until now with 96% of all understood types lost. At the end of the Triassic some 201 million years earlier, when 80% of all types vanished. The most popular mass termination took place at the end of the Cretaceous some 65 million years earlier, when 76% of all types went extinct, consisting of the big dinosaurs and ammonites. Small termination occasions likewise took place, like the termination of the Pleistocene megafauna at the end of the ice-age some 10,000 years earlier.

Researcher long discussed and still discuss about the aspects driving mass termination. Aspects adding to the disappearance of a types can be geological disasters, like volcanism, effects or environment modification, however likewise biological aspects, like competitors, illness or deficiency of resources. The most likely description for the most current mass termination at the end of the Cretaceous, is the effect of a big asteroid, interrupting the communities on an international scale. For the termination of numerous big mammal types at the end of the last ice-age amongst environment modification likewise the spread of hunter-gatherer societies might contributed.

In the last(*********************************** )years, a a great deal of mammal, bird, amphibian and reptile types went extinct. Specifically types with a minimal variety, living for instance just on islands, rapidly vanished after human beings showed up there, searching the little populations or damaging their natural environment. Research study released some years ago compared the current termination rate with the rebuilt rates throughout geologically peaceful times and mass terminations. At the time, the research study verified that existing termination rates are greater than would be gotten out of the fossil record, approaching a mass termination. Nowadays human activity is affecting the environment on an international scale and on an ever-accelerating rate.

According to a summary report from the United Nations, one in 4 recognized types are at danger of termination. Amphibians are amongst the most susceptible with 40% of the studied types at danger, followed by conifers with 34%, reef corals with 33%, cartilaginous fish like sharks and rays with 31%, mammals with 25% and birds with 14%. Amongst invertebrates, 27% of the studied shellfishes are at danger. Current studies have actually likewise revealed a significant collapse in insect populations

According to the report, just a quarter of Earth’s surface area is substantively without the effects of human activities, particularly in high latitudes, a location that will continue to diminish in the next years. Environment loss is a significant risk to biodiversity, followed by over-exploitation of animal populations, the spread of intrusive types and illness by human beings, contamination and environment modification.

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53621591848″ >

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Ecological deterioration by human activity is among the primary reasons for biodiversity loss.

D.Bressan

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In Earth’s long history approximated 99 % of all types ever living here went extinct. Termination becomes part of life’s history and termination of single types occurs all the time. In time lost types are ultimately changed as natural choice acts upon the survivors and brand-new types progress. Mass terminations are specified by the loss of a big part of the biodiversity in a (geologically speaking) brief period of time, when the development of brand-new types can’t compensate the losses. This can be seen likewise in the geological record.

5 huge mass termination occasions are acknowledged by paleontologists. At the end of the Ordovician some 443 million years earlier, when an approximated 86 % of all marine types vanished. At the end of the Devonian some 360 million years earlier, when 75 % of all types disappearance. At the end of the Permian some 250 million years earlier, the worst termination occasion up until now with 96 % of all understood types lost. At the end of the Triassic some 201 million years earlier, when 80 % of all types vanished. The most popular mass termination took place at the end of the Cretaceous some 65 million years earlier, when 76 % of all types went extinct, consisting of the big dinosaurs and ammonites. Small termination occasions likewise took place, like the termination of the Pleistocene megafauna at the end of the ice-age some 10, 000 years earlier.

Researcher long discussed and still discuss about the aspects driving mass termination. Aspects adding to the disappearance of a types can be geological disasters, like volcanism, effects or environment modification, however likewise biological aspects, like competitors, illness or deficiency of resources. The most likely description for the most current mass termination at the end of the Cretaceous, is the effect of a big asteroid, interrupting the communities on an international scale. For the termination of numerous big mammal types at the end of the last ice-age amongst environment modification likewise the spread of hunter-gatherer societies might contributed.

In the last 400 years, a a great deal of mammal, bird, amphibian and reptile types went extinct. Specifically types with a minimal variety, living for instance just on islands, rapidly vanished after human beings showed up there, searching the little populations or damaging their natural environment. Research study released some years ago compared the current termination rate with the rebuilt rates throughout geologically peaceful times and mass terminations. At the time, the research study verified that existing termination rates are greater than would be gotten out of the fossil record, approaching a mass termination. Nowadays human activity is affecting the environment on an international scale and on an ever-accelerating rate.

According to a summary report from the United Nations , one in 4 recognized types are at danger of termination. Amphibians are amongst the most susceptible with 40 % of the studied types at danger, followed by conifers with 34 %, reef corals with 33 %, cartilaginous fish like sharks and rays with 31 %, mammals with 25 % and birds with 14 %. Amongst invertebrates, 27 % of the studied shellfishes are at danger. Current studies have actually likewise revealed a significant collapse in insect populations

.

According to the report, just a quarter of Earth’s surface area is substantively without the effects of human activities, particularly in high latitudes, a location that will continue to diminish in the next years. Environment loss is a significant risk to biodiversity, followed by over-exploitation of animal populations, the spread of intrusive types and illness by human beings, contamination and environment modification.

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