Approximately how many animal species exist, and how many major divisions are recognized?

Approximately how many animal species exist, and how many major divisions are recognized?

• A. A few thousand species and 5 divisions
• B. Over 10 million species and 60 divisions
• C. Over 1 million species and about 30 divisions
• D. Roughly 100 thousand species and 20 divisions

Answer: (C)

Think about biodiversity at a high level: how many animal species have been described by scientists, and how many large groups (phyla) are recognized as major branches of the animal kingdom. Right now, scientists have described a little over a million animal species. In terms of major divisions, there are about 30 recognized phyla, though the exact number can vary a bit with different classification schemes. So the statement that best fits these widely cited figures is: over 1 million described species and about 30 divisions. The other options either understate the number of described species or overstate the number of major divisions.

Think about biodiversity at a high level: how many animal species have been described by scientists, and how many large groups (phyla) are recognized as major branches of the animal kingdom. Right now, scientists have described a little over a million animal species. In terms of major divisions, there are about 30 recognized phyla, though the exact number can vary a bit with different classification schemes.

So the statement that best fits these widely cited figures is: over 1 million described species and about 30 divisions. The other options either understate the number of described species or overstate the number of major divisions.