Question

How many mass extinction of species are there on records since the origin and diversification of life on earth? How is the present episode different? What is the result of loss of biodiversity in a region?

Answer 1

There were five (5) major extinction events in history and scientists have spoken about these events based on species fossil record. For example, scientific evidence of examples of “coral reefs” etc as explained below. Mass extinction events have been identified periodically through the history of life, with five major extinctions occurring since the Cambrian period each of which eliminated over 20% of extant life, and with lesser mass extinctions being even more frequent.

1. The first major extinction took place at the end of the Ordovician period & this extinction is mainly observed based on the fossil record of majority of 60% of terrestrial and aquatic life including oceans

2. The second mass extinction was taken place 360 million years ago during the Late Devonian period. The evidence has presented by scientists formation of “nurtured coral reefs” in accordance with environmental conditions as they extinct now

3. The third mass extinction has happened during the end of Permian with loss of life & scientists have explained that approximately 70 to 90% of marine life was extinct in this period. Again reefs have not appeared

4. The fourth mass extinction event took place at the end of Triassic period & extinction of half of all marine invertebrates took place in this period & approximately 85% land quadrupeds were extinct.

Prepare a short paragraph identifying your extinction event, the prevalent theory as to its cause, and any plausible alternative explanations you found:

The fifth major extinction happened during the end-Cretaceous period approximately 65 million years ago. The extinction of dinosaurs species has happened in this period due to environmental conditions & continental drift with natural calamities.

There were five (5) major extinction events in history and scientists have spoken about these events based on species fossil record. For example, scientific evidence of examples of “coral reefs” etc as explained below. Mass extinction events have been identified periodically through the history of life, with five major extinctions occurring since the Cambrian period each of which eliminated over 20% of extant life, and with lesser mass extinctions being even more frequent.

1. The first major extinction took place at the end of the Ordovician period & this extinction is mainly observed based on the fossil record of majority of 60% of terrestrial and aquatic life including oceans

2. The second mass extinction was taken place 360 million years ago during the Late Devonian period. The evidence has presented by scientists formation of “nurtured coral reefs” in accordance with environmental conditions as they extinct now

3. The third mass extinction has happened during the end of Permian with loss of life & scientists have explained that approximately 70 to 90% of marine life was extinct in this period. Again reefs have not appeared

4. The fourth mass extinction event took place at the end of Triassic period & extinction of half of all marine invertebrates took place in this period & approximately 85% land quadrupeds were extinct.

Prepare a short paragraph identifying your extinction event, the prevalent theory as to its cause, and any plausible alternative explanations you found:

The fifth major extinction has happened during the end-Cretaceous period approximately 65 million years ago. The extinction of dinosaurs species has happened in this period due to environmental conditions & continental drift with natural calamities.

The sixth mass extinction was different because it is occurring at a faster rate than the previous extinctions.

Biodiversity increases the productivity of the ecosystem, more diversity means, more species can exist. This ensures different types of resources available for the humans. For example, among crops, different crop species provide different nutrients, different medicinal plants, etc. So, loss of biodiversity negatively affects all these factors.