NS biologists! I am calling on you for guidance!

6 million and 4

There is a massive number of different Classes, under each of the various Phyla of living organisms. I doubt anyone has an official count listed somewhere.

first off, it's not set in stone that there are 2 domains. some go by 3 domains: archaea, bacteria, and eukarya

then there are the 6 kingdoms


but there are 35 known animal and 12 known plant phyla, then include those in the other kingdoms. many more.


then when you get lower than phyla you're getting into territory where it's really hard to say how many there are. I mean, once you get to species level there are estimates from 2 to 100 million. so really hard to say.

According to my microbiology textbook there are 3 domains, you should prob start with getting that right before worrying about the classes...

According to Woese et al. (1990) there are 3 domains. In 1998 Thomas Cavalier-Smith published his works with 2 domains, and seeing as this is the most recent and accepted system, I have listed it. This wasn't meant to be an argument about domains though.

I was referencing animals only below phyla, should have mentioned. Surely there is a list of clearly classified classes, only including definite classifications? If not, oh well...

probably about 100-150. I'll check in some of my books. give me a few minutes.

Naming branches of the tree of life is arbitrary and dumb, write that down.

For kingdoms, there are three, or six. Bacteria, Archaea, Eurkarya. Some further divide Eukarya into Protists, Fungi, Plants and Animals.

You are a shit researcher when it comes to the internet, right here from the Wikipedia page on Biological Classes:

http://en.wikipedia.org/wiki/Class_(biology)

"The composition of each class is determined by a taxonomist. Often there is no exact agreement, with different taxonomists taking different positions. There are no hard rules that a taxonomist needs to follow in describing a class, but for well-known animals there is likely to be consensus. For example, dogs are usually assigned to the phylum Chordata (animals with notochords); in the class Mammalia; in the order Carnivora."

Yeah in College we learned that there was a completely new phylum of critter living on like lobsters antennae. So there's prolly an estimate only for the number of classes

I am glad I read your post earlier about being #2 shit talker :p

Yes I suck at researching.

What a stupid question.

What a clever answer :)