Jacksury Puerta

Extinction is the process by which a species become extinct, no longer existing and living in the world. Extinction is a normal part of evolution. Species come and go continually, around 99.9% of all those that have ever existed are now extinct. Mass extinctions are events in which a very significant percentage of the species on the planet go extinct.

Ordovician-Silurian, 435 million years ago Late Devonian, 370 million years ago Permian, 250 million years ago Triassic, 205 million years ago Cretaceous-Tertiary, 65 million years ago

439 million years ago Caused by a drop in sea level as glaciers formed, then by rising sea levels as glaciers melted. Approximately 60% of marine genera were killed and 25% of marine families

364 million years ago series of extinction over several million years Caused by a asteroid impact and global cooling after the impact Approximately 57% of the genera were killed and 22% of marine families Life in the shallow sea were the most affected

Known as the “Great Dying”, most severe extinction 96% of all marine species were killed 70% of land-living animal life were killed Caused by change in climate and sea level when forces of the earth’s continents merge together.

2 or 3 phases of extinction 52% of marine genera and 22% of marine families Caused by massive floods or lava erupting from central Atlantic province led by global warning

Known as the K/T extinction Famous for the death of the dinosaurs 75% of all species became extinct Happened at a rapid rate Caused: by a volcanic event that produced the Deccan traps of India An asteroid hit somewhere in the golf of Mexico in the Yucatan Peninsula

Known as the Holocene extinction This extinction event started at the end of the last ice age, around 13,000 BP. Rapid pace - hundred years rather than thousand years seen by the big five mass extinction. The rapid loss of species we are seeing today is estimated to be between 1,000 and 10,000 times higher than the natural extinction rate. E. O. Wilson estimates that 30,000 species per year (or three species per hour) are being driven to extinction.

The Extinction of nearly all forms of the large mammals known as Megafauna, and the remaining species almost all threatened with extinction in the near future.

Unlike previous extinctions they were caused by climate change, the current crisis is caused by human activities. Habitat destruction Pollution Overpopulation Over-harvesting (hunting, fishing, and gathering) Invasive species By the year 2100, due to human activities half of the world's marine and land species will go extinct.

This graph shows the rise in extinctions since the human population

The world’s leading scientists suggest that conservation measures, sustainable development, stabilization of the human population and the support of environmentally responsible economic development will be essential in halting the extinction crisis.

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