In fact, scientists do not know how many types of plants, animals, fungi and bacteria there are on Earth. According to the latest estimate, there will be 2 billion, and that will change at some point.
One thing we do know: the western black rhino, the Tasmanian tiger and the woolly mammoth are among the animals whose populations have dropped to zero at some point, and species extinction could have been a thousand times faster at the hands of humans.
A species dies due to environmental factors or developmental problems. Species are constantly disappearing from the earth, and their frequency varies over time. A quarter of mammals are at risk of extinction, according to IUCN Red List estimates.
To some extent, extinction is a natural phenomenon. Changes in habitat and weakening reproductive trends, among other things, can cause a species’ mortality rate to exceed the birth rate long enough that eventually no specimens are left.
Humans are also driving other species to extinction through hunting and poaching, the introduction of invasive species into the wild, pollution, and the conversion of wetlands and forests into farmlands and urban areas. Rapid population growth also leads to species extinction through the destruction of natural habitats.
One of the most famous species in danger of extinction at the hands of humans, the dodo is a bird that lived primarily on the island of Mauritius and was best known through its appearance in Lewis Carroll’s book “Alice in Wonderland”. The dodo was first mentioned in the late 16th century by Dutch sailors and was last seen in 1662, after it became extinct due to hunting. The passenger pigeon, billions of which often flew across North American skies when Europeans reached the continent, became extinct when the latter died in 1914 at the Cincinnati Zoo.
Six mass extinctions
Fossils show that there were five earlier periods in history when an unusually large number of species became extinct. These periods are known as mass extinctions. Most species on Earth became extinct about 266 million to 252 million years ago during the Permian extinction.
However, these losses also paved the way for the evolution of the dinosaurs, where mass extinctions create an opportunity for new species to emerge. The dinosaurs ended about 65 million years ago in another mass extinction at the end of the Cretaceous period. A large crater near the Yucatan Peninsula in Mexico indicates that an asteroid may have collided there. Scientists believe that volcanic eruptions in India caused global warming, which may also have contributed to the mass extinction.
Scientists debate whether Earth is now in the midst of a sixth mass extinction. If so, it could be the fastest of all, at 1,000 to 10,000 times the base rate at which species are going extinct, which equates to one to five species each year. Man is largely responsible for this remarkable development. Scientists believe that pollution, deforestation, and poaching may be doomed to extinction by 2100 for half of Earth’s terrestrial and marine animals.
The slow rise in surface temperatures due to increased concentrations of greenhouse gases is likely to cause many species to move toward the poles and higher into the mountains to stay in habitats with the same climate. But not all species will be able to adapt quickly enough to avoid extinction, and many species are expected to disappear.
What can we do about this?
Using less fossil fuels by lowering the thermostat, reducing driving and recycling is a good way to slow the rate of extinction. Eating less meat and avoiding certain products, such as ivory, which comes from endangered species, can also make a difference. At home, local wildlife can be protected by disposing of waste in closed bins, reducing water consumption and avoiding the use of herbicides and pesticides.