86 Percent of Species Still Unknown

[Alpha Female]

I found this article rather interesting, and never really realized how many species are still unknown. ^^

Even after centuries of effort, some 86 percent of Earth's species have yet to be fully described, according to new study that predicts our planet is home to 8.7 million species.
That means scientists have cataloged less than 15 percent of species now alive—and current extinction rates mean many unknown organisms will wink out of existence before they can be recorded.

The study was driven by a simple question: "Are we within reach of finding all species, or are we way off?" said study co-author Boris Worm of Canada's Dalhousie University.

"The answer is, we are way off."

Two hundred and fifty years after Swedish botanist Carl Linnaeus devised a formal system for classifying the diversity of nature, the catalog for some classes of living things—such as mammals and birds—is nearly complete, the study says. But the inventories for other classes are woefully sparse.

For instance, only 7 percent of the predicted number of fungi—which includes mushrooms and yeasts—has been described, and less than 10 percent of the life-forms in the world's oceans has been identified.

What's been discovered so far are "those things that are easy to find, that are conspicuous, that are relatively large," Worm said.

"There is an age of discovery ahead of us when we could find out so much more of what lives with us on this planet."

Counting Earth's Millions
So far, some 1.2 million species are known to science. To calculate the percentage of unknown species, Worm and colleagues first had to answer one of the great questions of ecology: How many species live on the Earth?

Previous guesses ranged from three million all the way to a hundred million.
To gain a more precise answer, the authors examined the categories into which all species are grouped.

Scientists lump similar species together into a broader grouping called a genus, similar genera into a still broader category called a family, and so on, all the way up to a supercategory called a kingdom.

There are five kingdoms: animals, plants, fungi, chromists—including one-celled plants such as diatoms—and protozoa, or one-celled organisms.

Worm's team estimated the total number of genera, families, orders, classes, and phyla—a designation above class—in each kingdom. That's a relatively easy task, since the number of new examples in these categories has leveled off in recent decades.

By contrast, the number of newly discovered species continues to rise sharply.

Using complex statistics, Worm and colleagues used the number of genera, families, and so on to predict Earth's number of unknown species, and their calculations gave them a number: 8.7 million.

An Issue of Statistics

Some experts called the research, published August 23 in the journal PLoS Biology, reasonable.

The new study "takes a hugely clever approach, and I think it's going to turn out to be a pretty important study," said Lucas Joppa, a conservation ecologist at Microsoft Research, the research branch of the software giant.

"If I asked you to count out 8.7 million pennies, that would take you a while, even if you had a whole lot of people doing it."

But Dan Bebber, an ecologist at the environmental group Earthwatch Institute, said the study relies on improper statistical methods.

The study team used a method called linear regression to calculate the number of Earth's species. But Bebber thinks this method is the wrong one for the data, and that the team should have used a technique known as ordinal regression.

As a result, the true number of species could be much higher or lower than 8.7 million, he said.

Nature's Library Disappearing
Overall, formally categorizing a new organism is a lot more complicated than discovering one, study co-author Worm said. Scientists must compare their specimen to museum samples, analyze its DNA, and complete reams of paperwork.

"It's a long process," he said. Most scientists "will describe dozens of species in their lifetime, if they're really lucky."

Unfortunately, extinction rates have accelerated to ten to a hundred times their natural level, Worm added.

The information to be gained when new species are discovered "is nature's library, and we've only begun to decipher the first ten books," Worm said.

"We're throwing out entire books without having a look at them."

Source: http://news.nationalgeographic.com/news ... s-science/

[Larkarl]

Thanks for sharing this article, flower. Just goes to show how much diversity our own planet has- space may be the "final frontier", but Earth still has many exciting things to show us.

[Chemuhk]

Geez, I knew that many of the species on earth were not cataloged, but I had no idea it was this many! It makes you think about how the amount of things we know pales in comparison to what we don't.

[Tita]

Neat article, thank you for sharing. I didn't realize... O.o

[failwolf56]

Thanks for sharing this article, flower. Just goes to show how much diversity our own planet has- space may be the "final frontier", but Earth still has many exciting things to show us.

Feww, that is quite a lot of species that we;ve got here on earth. I agree with Larkal here, it seems like the human race knows so much, but when one really thinks about the abundance of species just within the earth, it's as if we know only a fraction of what is really "out there". Thanks for sharing m&m C:

[ShadowLycan]

This is truly an interesting article, just to know how many animals there are that are still left unknown.

[Leopardstar919]

Quite interesting... I never knew how many species we still haven't explored, but thats a LOT! I would have guessed that we have dicovered more then that. But, I find that quite interesting. Thanks for sharing flower. ^^

[Raining Precedence]

That's certainly a large number of species--I don't expect to see half of them in my lifetime. However, I believe it's fairly reasonable. There are many places on Earth we have yet to explore fully, and many things left undiscovered. The world is a vast thing, and I doubt that we'll ever uncover the whole 86% of species that are still unknown. Very neat read, and I've learned something new today.

[Selize]

That's certainly a large number of species--I don't expect to see half of them in my lifetime. However, I believe it's fairly reasonable. There are many places on Earth we have yet to explore fully, and many things left undiscovered. The world is a vast thing, and I doubt that we'll ever uncover the whole 86% of species that are still unknown. Very neat read, and I've learned something new today.

I never really thought of that. I always suspected that 86% of animals unknown still was surprising but how you put it..... Just makes it easier to understands. Anyway, thanks for sharing Alpha Female, it was interesting.

[WolvesOfTheSeas]

Whoa seriously this is very interesting Wow that a lot of animal still unknown i Would like to learn more! Seriously So thank you Alpha Female for sharing this in public

[Nordue]

• It’s going to be tough to try and catalogue all the life of this planet, I think. The old taxonomic methods of species identification may no longer be enough. Not that they ever were, from what I could tell .
  
  I agree with the article when it says that the 'bigger' organisms are the easiest to identify, mainly referring to mammals. They are the easiest to id with traditional taxonomy.
  
  I have a budding interest in a relatively new technological identification method called DNA Barcoding. DNA Barcoding currently favours/is limited to eukaryotic organisms. Eukaryotes have mitochondria in their cells, which in turn contains the genome needed for species identification via DNA Barcoding. This basically leaves out bacteria. The problem with bacteria and other prokaryotic organisms is that frequent mutations of their genome make them difficult to identify via DNA Barcoding, as the genome that distinguishes them as a distinct species is always changing.
  
  Insects are another challenge for Barcoding. I read that 75% of insect species suffer from a disease that disrupts the mitochondrial genome, making it unable to be recognized for species identification.
  
  I am hoping to specialize at into Biodiversity, in case you were wondering . But I'd like to think that I could help with the DNA Barcoding project someday, and help to catalogue all life!
  
  I should make a DNA Barcoding topic here on WQ if it hasn't been done already, methinks.