From white Bengal tigers to black rhinoceroses, animals on the endangered species list include some of the most beautiful and ancient creatures in the world. With thousands of species qualifying as threatened, Endangered Species Day, which is Friday, is a way to celebrate and advocate for the protection of some of the plants and animals at the highest risk for extinction.

Below are facts, quotes and a considerable amount of information about Endangered Species Day.

1. Endangered Species Day takes place on the third Friday each May and is marked with events at conservation centers and other locations nationwide. The Endangered Species Coalition, a nonprofit that educates the public and advocates on behalf of endangered species, has published a list of this year’s events here.

2. Extinction is a natural process. It usually occurs at a rate of a few species per year but is currently taking place at a rate of several thousand species per year, scientists estimate.

3. The Endangered Species Act, enacted in 1973 and signed into law by President Richard Nixon, helped set up guidelines in the U.S. for protecting endangered species by categorizing them as threatened or extinct and creating protections to prevent them from being hunted or fished.

4. “The Congress, the Administration and the public all share a profound commitment to the rescue of our natural environment, and the preservation of the Earth as a place both habitable by and hospitable to man,” Nixon said in 1970 when he encouraged Congress to do more for environmental regulation and conservation.

5. Individuals can donate to the National Wildlife Federation, the largest private, nonprofit conservancy, as well as the World Wildlife Fund and a series of conservation lands and organizations dedicated to the protection of specific species.

6. Three rhino species — the Javan, Sumatran and black rhino — are categorized as critically endangered by the International Union for Conservation of Nature (IUCN) Red List of Threatened Species.

rhino This photo, taken Jan. 27, 2015, shows a northern white female rhinoceros named Najin, one of only five members of the subspecies left on the planet, at Ol Pejeta conservancy, north of the Kenyan capital, Nairobi, where three of the rhinos are housed. Photo: AFP/Getty Images

7. “It is time for us now as a nation to exercise the same reasonable foresight in dealing with our great natural resources that would be shown by any prudent man in conserving and widely using the property which contains the assurance of well-being for himself and his children,” said President Theodore Roosevelt at the 1908 conference on the conservation of natural resources.

8. The hawksbill sea turtle, which is listed as critically endangered, has existed for 100 million years.

9. “When it comes to looking after all the species that are already endangered, there’s such a lot to do that sometimes it might all seem to be too much, especially when there are so many other important things to worry about. But if we stop trying, the chances are that pretty soon we’ll end up with a world where there are no tigers or elephants, or sawfishes or whooping cranes, or albatrosses or ground iguanas. And I think that would be a shame, don’t you?” wrote author Martin Jenkins in his book “Can We Save the Tiger?”