extinctions¶
we are the first species to cause an extinction event
| Extinction Event | Cause 1 | Cause 2 | Cause 3 |
|---|---|---|---|
| Ordovician-Silurian | Global cooling | Glaciation | Decreased sea level due to glaciation |
| Late Devonian | Climate change | Ocean anoxia | Habitat loss due to sea level fluctuations |
| Permian-Triassic | Global warming | Ocean acidification | Habitat loss due to sea level fluctuations |
| Triassic-Jurassic | Global warming and CO2 emissions | Asteroid impact | Habitat loss due to sea level fluctuations |
| Cretaceous-Paleogene | Asteroid impact | Global cooling | Habitat loss due to asteroid impact |
| Holocene | Human activity | Climate change | Habitat loss due to human activity |
| Extinction Event | Estimated Date | Percentage of Species Lost |
|---|---|---|
| Ordovician-Silurian Extinction | 440 million years ago | 85% |
| Late Devonian Extinction | 365 million years ago | 75% |
| Permian-Triassic Extinction | 250 million years ago | 96% |
| Triassic-Jurassic Extinction | 200 million years ago | 80% |
| Cretaceous-Tertiary Extinction | 65 million years ago | 76% |
| Holocene Extinction | 10,000 years ago to present | Up to 17% projected by 2100 |
we estimate there are currently 1.9 million species, natural disaster routinely cause extinction
Ocean anoxia can be caused by a variety of factors, including excessive nutrient runoff from land, which leads to an overgrowth of algae and ultimately oxygen depletion when the algae dies and decomposes; ocean circulation changes; volcanic activity; and changes in ocean chemistry, such as increased atmospheric carbon dioxide levels leading to ocean acidification. Additionally, factors such as warming ocean temperatures and changes in sea level can exacerbate the effects of anoxia.
Ocean acidification is caused by the absorption of excess carbon dioxide (CO2) from the atmosphere into the ocean, which lowers the pH level of seawater, making it more acidic. CO2 dissolves in seawater and reacts with water molecules to form carbonic acid (H2CO3), which in turn releases hydrogen ions (H+) that increase the acidity of the water. The increased acidity can have negative effects on marine life, particularly on shell-forming organisms like corals, mollusks, and some planktonic species.
Global cooling can be caused by a variety of factors, including changes in the Earth's orbit, volcanic eruptions, and fluctuations in solar radiation. The cooling effect of volcanic eruptions is due to the release of large amounts of sulfur dioxide and ash into the atmosphere, which can block the sun's rays and reduce the amount of solar radiation that reaches the Earth's surface. Changes in the Earth's orbit can also affect the amount and distribution of solar radiation, which can impact global temperatures. Additionally, variations in solar activity, such as the 11-year solar cycle, can influence the amount of solar radiation that reaches the Earth's surface and impact global temperatures.
| Reference | Author(s) | Publication Date |
|---|---|---|
| "The Sixth Extinction: An Unnatural History" | Elizabeth Kolbert | 2014 |
| "Biological annihilation via the ongoing sixth mass extinction signaled by vertebrate population losses and declines" | Gerardo Ceballos, Paul R. Ehrlich, and Peter H. Raven | 2017 |
| "The Anthropocene is functionally and stratigraphically distinct from the Holocene" | Colin N. Waters et al. | 2016 |
| "Accelerated modern human–induced species losses: Entering the sixth mass extinction" | Anthony D. Barnosky et al. | 2011 |
| "The biodiversity of species and their rates of extinction, distribution, and protection" | Stuart L. Pimm et al. | 2014 |
| "Historical overfishing and the recent collapse of coastal ecosystems" | Jeremy B.C. Jackson et al. | 2001 |
| "The Amphibian Extinction Crisis: What Will Not Work" | Michael J. Lannoo | 2005 |
| "Trophic Downgrading of Planet Earth" | James A. Estes et al. | 2011 |
| "Conservation: Earth is home to millions of species. Now we're tracking the decline of almost every one" | Damian Carrington | 2017 |
| "Extinction risk from climate change" | Mark C. Urban | 2015 |
sixth extinction¶
top 10 causes for human extinction¶
- Natural disasters: This can include events such as supervolcanoes, asteroid impacts, and large-scale earthquakes and tsunamis.
- Pandemics: The spread of a highly infectious and lethal disease could potentially cause a global pandemic leading to human extinction.
- Nuclear war: The use of nuclear weapons in a global conflict could result in widespread destruction and the release of harmful radioactive material into the atmosphere.
- Climate change: Rising global temperatures and changing weather patterns caused by human activities could lead to food and water shortages, as well as increased natural disasters, and render the planet uninhabitable.
- Artificial intelligence: The development of highly advanced artificial intelligence that surpasses human control could pose a threat to humanity.
- Genetic engineering: Unintended consequences or misuse of genetic engineering technologies could result in the creation of new, potentially deadly diseases.
- Collapse of civilization: The collapse of modern society due to factors such as resource depletion, economic instability, and political conflict could lead to widespread violence and chaos.
- Cyborgs: The creation of highly advanced cyborgs (part human, part machine) could result in the displacement of the human race and eventual extinction.
- Aliens: The discovery of hostile alien life forms could pose a threat to humanity's survival.
- Eco-collapse: The widespread destruction of the natural world and loss of biodiversity could result in the collapse of the ecosystems that support human life.
cloning endangered species¶
Cloning is the process of creating an organism that is genetically identical to another organism through a process called somatic cell nuclear transfer (SCNT). While many different animals have been cloned over the years, the most complex animal that has been successfully cloned is the sheep, specifically the famous sheep named Dolly.
Dolly the sheep was the first mammal to be cloned using the SCNT technique. She was born on July 5, 1996, and was created by scientists at the Roslin Institute in Edinburgh, Scotland, using cells from the udder of an adult sheep. Dolly was an exact genetic copy of the sheep from which the cells were taken.
The successful cloning of Dolly was a major scientific breakthrough and opened up new possibilities for genetic research and animal cloning. However, it also raised ethical concerns about the use of cloning technology and the potential consequences for both animal welfare and human health.
Since Dolly, many other animals have been successfully cloned, including cats, dogs, cows, pigs, and even some endangered species.