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How Many Species of Animal are There?

Michael Anissimov
Michael Anissimov
Michael Anissimov
Michael Anissimov

There are about 1,250,000 identified species of animal. This includes 1,190,200 invertebrates, among them 950,000 insects, 70,000 mollusks, 40,000 crustaceans, and 130,200 others. There are about 58,800 identified vertebrates, including 29,300 fish, 5,743 amphibians, 8,240 reptiles, 9,800 birds, and 5,416 mammals. As a comparison, almost 300,000 plant species are known.

Importantly, the numbers above do not account for species that have not yet been captured or described scientifically. Scientists estimate there may be as many as 10 - 30 million unidentified insect species, many of them living in the rainforest, and up to 1 million mite species. Mites are small arthropods, a group of animals related to, but not the same as, insects.

Earthworms are a type of invertebrate.
Earthworms are a type of invertebrate.

It is clear that modern science is not aware of all the species on the planet. When Carl Linnaeus and his pupils set out to record all the species they could in the mid-18th century, they found just over 15,000 species of animal. Today, estimates of the total number range from 2 to 30 million. In addition to all the animals, there are between 10 million and 1 billion species of bacteria and archaea. What's more, the number of species today is thought to represent only 1% of all species that have ever lived, since mass extinctions in the past have likely killed off as many as 97% of all species.

Mammals are a part of the vertebrates species.
Mammals are a part of the vertebrates species.

Unfortunately, the number of species of animal on Earth today are dropping. An event known as the Holocene extinction event is underway, caused by humans. When humans initially spread across the world, many species went extinct, including all of the Pleistocene megafuna, which were wiped out entirely by 9,000 years ago. These include the mammoth, mastodon, auroch, saber-toothed tiger, cave bear, short-faced bear, dire wolf, camelops, wooly rhinoceros, giant lizards, many marsupials, and others. Today, with booming human populations, global warming, and widespread deforestation and poaching, the destruction of thousands of species is continuing.

Michael Anissimov
Michael Anissimov

Michael is a longtime AllTheScience contributor who specializes in topics relating to paleontology, physics, biology, astronomy, chemistry, and futurism. In addition to being an avid blogger, Michael is particularly passionate about stem cell research, regenerative medicine, and life extension therapies. He has also worked for the Methuselah Foundation, the Singularity Institute for Artificial Intelligence, and the Lifeboat Foundation.

Learn more...
Michael Anissimov
Michael Anissimov

Michael is a longtime AllTheScience contributor who specializes in topics relating to paleontology, physics, biology, astronomy, chemistry, and futurism. In addition to being an avid blogger, Michael is particularly passionate about stem cell research, regenerative medicine, and life extension therapies. He has also worked for the Methuselah Foundation, the Singularity Institute for Artificial Intelligence, and the Lifeboat Foundation.

Learn more...

Discussion Comments

anon958326

@anon142504:

Genesis 6:15 in the Bible tells us the Ark's dimensions were at least 135 meters long (300 cubits), 22.5 meters wide (50 cubits), and 13.5 meters high (30 cubits). That's 450 feet long, 75 feet wide, and 45 feet high! It could have been larger, because several larger-sized cubits were used. But the 45-centimeter (18-inch) cubit is long enough to show the enormous size of the Ark. It is typically measured from the tip of the finger to the elbow.

According to this article there are 1,250,000 species of animal. Noah brought on board only those animals with the "breath of life" in their nostrils. Eliminate the invertebrates and fish and insects. I am now coming up with a loose number of 30,500 animals that needed to be saved according to today's standards.

But another point to consider is the variety of species. Have you ever heard of a Puggle (pug + beagle)? A Labra-doodle? (lab + poodle). These are relatively new breeds of dogs that did not exist thousands of years ago. Rather than a wolf, coyote, fox, dog, there was probably one common ancestor. This does not prove evolution, but rather the principles of eugenics.

The same can be said for wild animals that breed with each other (lion + tiger) or even beasts of burden such as a mule (horse + donkey). My point is: there were probably not as many species 4,500 years ago before the flood. There was probably a common ancestor for the animals we have today, but not as many as there are today. Based on the dimensions of the ark, and the fact that Noah probably was smart enough to take baby animals on board (because they would save space) it is totally plausible.

Belief has nothing to do with it. It is explained with math and science. The problem is whether folks are willing to put the time in to figuring it out. The Bible says to meditate on the scriptures daily. Meditation is not emptying your mind as pagans would have you do. Meditation in the biblical sense is to study repeatedly and focus on one word or phrase.

Personally, I believe that a cubit would have been larger than 18 inches. We find evidence of large animals from the past (giant sloth, dinosaurs, giant turtles, sharks, etc.) There is no reason to believe that humans would not have been larger, too. The Bible teaches that there was lush vegetation over the entire earth with some lakes and small seas. There was also a protective layer of atmosphere made of ice or water. This would filter out radiation, compress the atmosphere to increase air pressure and act as a thermal blanket. More detail is needed, but I'm on my lunch break now -- but these conditions would stand up to scientific scrutiny, and would explain how things would grow larger and live longer. Therefore I believe that the Ark was probably larger than described above if one uses the fingertip to elbow measurement for a cubit.

anon319371

Do you mean to say that the same God who fed 5000 men with 5 loaves of bread and 2 fish couldn't possibly bend the rules of science?

Christians believe in plenty of miracles. We never claimed they could be explained by science. If they could, they would not be miracles. I was so caught up in the miracle of God causing a flood to cover the entire earth at his command, I overlooked the underlying miracle of the koala, kangaroo, and polar bear placement. Thanks for the new perspective and inspiration. God bless.

anon142504

Yeah, this is one of those problems with Noah. Believers say, do not try to comprehend it, you have to believe!

whatever nonsense it may sound.

anon121744

Very interesting facts. It makes one wonder how Noah got all these species, including polar bears from the Arctic, penguins from the Antarctic, kangaroos and koalas from Australia etc. on board; and how he returned them to their native environments. And this doesn't include the dinosaurs, that fundamentalists claim were also around at that time!

FirstViolin

That's crazy how few species of mammals there are compared to other categories of species. It makes you think about how rare animals with only a few species, like pandas, are (there's only two species of pandas).

To me, that makes helping endangered species even more important -- we need to do all we can to prevent the extinction of species.

TunaLine

Out of that, how many species of animals are endangered, I wonder?

rallenwriter

Wow, nice article. I had been looking all over for some definitive answers for a project on animal species that I'm trying to put together for my second graders. (I'm calling it "A to Z Animals").

This was very helpful, thank you.

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    • Earthworms are a type of invertebrate.
      By: Lsantilli
      Earthworms are a type of invertebrate.
    • Mammals are a part of the vertebrates species.
      By: Kjersti
      Mammals are a part of the vertebrates species.
    • There are about 1,250,000 identified species of animal.
      By: JohanSwanepoel
      There are about 1,250,000 identified species of animal.
    • Many animals, such as the sun bear, live in the world's rainforests.
      Many animals, such as the sun bear, live in the world's rainforests.
    • Rainforests are home to a variety of animals, including gnatcatchers.
      Rainforests are home to a variety of animals, including gnatcatchers.
    • The resplendent quetzal is now being threatened due to the deforestation of the tropical forests.
      The resplendent quetzal is now being threatened due to the deforestation of the tropical forests.