Almost all potatoes cultivate d, sold, and consumed, for instance, are from a single species, the Russet Burbank. Potatoes, native to the Andes Mountains of South America, have dozens of natural varieties. The genetic variation of wild potatoes allows them to adapt to climate change and disease.
For Russet Burbanks, however, farmers must use fertilizer s and pesticides to ensure healthy crops because the plant has almost no genetic variation. Plant breeders often go back to wild varieties to collect genes that will help cultivated plants resist pests and drought, and adapt to climate change.
However, climate change is also threatening wild varieties. That means domesticated plants may lose an important source of traits that help them overcome new threats. The Red List has seven levels of conservation: least concern, near threatened, vulnerable, endangered, critically endangered, extinct in the wild, and extinct. Each category represents a different threat level. Species that are not threatened by extinction are placed within the first two categories—least concern and near-threatened.
Those that are most threatened are placed within the next three categories, known as the threatened categories —vulnerable, endangered, and critically endangered. Those species that are extinct in some form are placed within the last two categories—extinct in the wild and extinct.
Classifying a species as endangered has to do with its range and habitat, as well as its actual population. For this reason, a species can be of least concern in one area and endangered in another.
The gray whale, for instance, has a healthy population in the eastern Pacific Ocean, along the coast of North and South America. The population in the western Pacific, however, is critically endangered. Least Concern Least concern is the lowest level of conservation. A species of least concern is one that has a widespread and abundant population. Human beings are a species of least concern, along with most domestic animal s, such as dogs and cats.
Many wild animals, such as pigeons and houseflies, are also classified as least concern. Near Threatened A near threatened species is one that is likely to qualify for a threatened category in the near future. Many species of violet s, native to tropical jungle s in South America and Africa, are near threatened, for instance. They have healthy populations, but their rain forest habitat is disappearing at a fast pace.
People are cutting down huge areas of rain forest for development and timber. Many violet species are likely to become threatened. Vulnerable Species The definitions of the three threatened categories vulnerable, endangered, and critically endangered are based on five criteria: population reduction rate, geographic range, population size, population restrictions, and probability of extinction.
Threatened categories have different threshold s for these criteria. As the population and range of the species decreases, the species becomes more threatened. This decline is measured over 10 years or three generations of the species, whichever is longer. A generation is the period of time between the birth of an animal and the time it is able to reproduce. Mice are able to reproduce when they are about one month old. Mouse populations are mostly tracked over year periods. An elephant's generation lasts about 15 years.
So, elephant populations are measured over year periods. A species is vulnerable if its population has declined at least 50 percent and the cause of the decline is known. Habitat loss is the leading known cause of population decline. A species is also classified as vulnerable if its population has declined at least 30 percent and the cause of the decline is not known. A new, unknown virus, for example, could kill hundreds or even thousands of individuals before being identified. An area of occupancy is where a specific population of that species resides.
This area is often a breeding or nesting site in a species range. The species is also vulnerable if that population declines by at least 10 percent within 10 years or three generations, whichever is longer. A species is vulnerable if it is restricted to less than 1, mature individuals or an area of occupancy of less than 20 square kilometers 8 square miles. These formulas calculate the chances a species can survive, without human protection, in the wild. Vulnerable Species: Ethiopian Banana Frog The Ethiopian banana frog Afrixalus enseticola is a small frog native to high- altitude areas of southern Ethiopia.
It is a vulnerable species because its area of occupancy is less than 2, square kilometers square miles. The extent and quality of its forest habitat are in decline.
Threats to this habitat include forest clearance, mostly for housing and agriculture. Vulnerable Species: Snaggletooth Shark The snaggletooth shark Hemipristis elongatus is found in the tropical , coastal waters of the Indian and Pacific Oceans. Its area of occupancy is enormous, from southeast Africa to the Philippines, and from China to Australia. However, the snaggletooth shark is a vulnerable species because of a severe population reduction rate. Its population has fallen more than 10 percent over 10 years.
The number of sharks is declining due to fisheries, especially in the Java Sea and Gulf of Thailand. They are sold in commercial fish markets, as well as restaurants. Galapagos kelp is classified as vulnerable because its population has declined more than 10 percent over 10 years. Climate change is the leading cause of decline among Galapagos kelp. El Nino , the natural weather pattern that brings unusually warm water to the Galapagos, is the leading agent of climate change in this area. Galapagos kelp is a cold-water species and does not adapt quickly to changes in water temperature.
Endangered Species 1 Population reduction rate A species is classified as endangered when its population has declined between 50 and 70 percent. A species is classified as endangered when its population has declined at least 70 percent and the cause of the decline is known.
A species is also classified as endangered when its population has declined at least 50 percent and the cause of the decline is not known. When a species population declines by at least 20 percent within five years or two generations, it is also classified as endangered.
Endangered Species: Siberian Sturgeon The Siberian sturgeon Acipenser baerii is a large fish found in rivers and lakes throughout the Siberian region of Russia. The Siberian sturgeon is a benthic species. Benthic species live at the bottom of a body of water. The Siberian sturgeon is an endangered species because its total population has declined between 50 and 80 percent during the past 60 years three generations of sturgeon.
On the federal level, the endangered species list is managed under the Endangered Species Act. Under the ESA, the federal government has the responsibility to protect endangered species species that are likely to become extinct throughout all or a large portion of their range , threatened species species that are likely to become endangered in the near future , and critical habitat areas vital to the survival of endangered or threatened species.
The Endangered Species Act has lists of protected plant and animal species both nationally and worldwide. When a species is given ESA protection, it is said to be a "listed" species. The Endangered Species Act is very important because it saves our native fish, plants, and other wildlife from going extinct. Once gone, they're gone forever, and there's no going back. Losing even a single species can have disastrous impacts on the rest of the ecosystem, because the effects will be felt throughout the food chain.
From providing cures to deadly diseases to maintaining natural ecosystems and improving overall quality of life, the benefits of preserving threatened and endangered species are invaluable.
When the U. In order to be listed as a candidate, a species has to qualify for protected status under the Endangered Species Act. Whether or not a species is listed as endangered or threatened then depends on a number of factors, including the urgency and whether adequate protections exist through other means. When deciding whether a species should be added to the Endangered Species List, the following criteria are evaluated:.
If the answer to one or more of the above questions is yes, then the species can be listed under the Endangered Species Act. Past generations would regard what we see as natural today as terribly damaged, and what we see as damaged today, our children will view as natural. Wooddell believes the most important thing one can do is to put pressure on Congress and elected leaders to create land management, pollution and other sustainable policies that will protect biodiversity and the environment.
A tortoise shell mirror Photo: Housing Works. Correction: This post was updated on April 3, to remove a sentence about cownose rays devastating scallop populations off of North Carolina. It turns out that other studies have challenged those findings. The Trump administration has put forth new rules that will significantly weaken the Endangered Species Act. What happened when something like the Dodo went extinct? When I think about extinction, I always wonder what would have happened if the dinosaurs had not become extinct.
I am late to the discussion about keystone species but since I have learned about the roles of these key animals to specific environments around the world I have tried and failed to see homo sapiens as a keystone species but rather I see us more like the ungulates, which when left unchecked by a corresponding predator, such as the wolf in the Yellow Stone Park scenario, would decimate any environment we occupy.
We are overpopulating, over consuming, over producing items that are harmful to the entire world such as plastics and what will keep us in check? Who will be our wolves? If humans disappeared from the earth, just suddenly vanished, I think the earth and all her flora and fauna would recover quickly.
Our intelligence should curb our avarice, but I fear we are too shortsighted and too quick to rationalize away the science which spells out the looming disaster brought on my our ignorance and greed. Endangered species are important. In my opinion, their absence can cause a break in the food chain or break synergies with other species, and thus a negative impact on them. One species and can change so much. Like a domino effect.
We should take care of every species. I have been searching for a reasonable explanation of preservation of endangered species, and the search continues still. Tigers, Elephants, Rhinos, Deers etc. Whereas, deforestation, excessive usage of fossil fuels, phytoplankton extinctions leading to global warming effects are easily understood, no such wide range of explanations and outcomes do exist on the extinction of species and their wide range of influences.
Still looking for a reasonable explanation…. Notify of. I agree to help cultivate an open and respectful discussion. Oldest Newest Most Voted. Inline Feedbacks. Renee Cho. Dianne Olsen. Deborah Hansen. In addition to primates, marine mammals — including several species of whales, dolphins, and porpoises — are among those mammals slipping most quickly toward extinction.
PLANTS Through photosynthesis, plants provide the oxygen we breathe and the food we eat and are thus the foundation of most life on Earth. They're also the source of a majority of medicines in use today.
Of the more than , known species of plants, the IUCN has evaluated only 12, species, finding that about 68 percent of evaluated plant species are threatened with extinction. Unlike animals, plants can't readily move as their habitat is destroyed, making them particularly vulnerable to extinction. Global warming is likely to substantially exacerbate this problem.
Already, scientists say, warming temperatures are causing quick and dramatic changes in the range and distribution of plants around the world. With plants making up the backbone of ecosystems and the base of the food chain, that's very bad news for all species, which depend on plants for food, shelter, and survival. Island reptile species have been dealt the hardest blow, with at least 28 island reptiles having died out since The main threats to reptiles are habitat destruction and the invasion of nonnative species, which prey on reptiles and compete with them for habitat and food.
Get the latest on our work for biodiversity and learn how to help in our free weekly e-newsletter. Saving Life on Earth Read our report on how we can tackle the extinction crisis before it's too late. Contact: Tierra Curry. Need to cite this webpage? The Center for Biological Diversity is a c 3 registered charitable organization. Tax ID: Restores the full power of the Endangered Species Act and quickly moves to protect all species that are endangered but not yet on the endangered species list.
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