| 1. | Class | 2. | Phylum |
| 3. | Family | 4. | Kingdom |
| 1. | Species → Genus → Family → Order → Class → Division → Kingdom |
| 2. | Species → Genus → Family → Class → Order → Division → Kingdom |
| 3. | Species → Genus → Order → Family → Class → Division → Kingdom |
| 4. | Genus → Species → Family → Order → Class → Kingdom → Division |
| 1. | Cladistics | 2. | Systematics |
| 3. | Taxonomy | 4. | Identification |
| 1. | Kingdom, Order, Phylum, Class, Family, Genus, Species |
| 2. | Kingdom, Phylum, Class, Order, Family, Genus, Species |
| 3. | Kingdom, Class, Phylum, Family, Order, Genus, Species |
| 4. | Kingdom, Order, Class, Phylum, Family, Genus, Species |
| 1. | Family | 2. | Order |
| 3. | Division | 4. | Genus |
| 1. | Increase |
| 2. | Decrease |
| 3. | Remain same |
| 4. | May increase in polar regions and decrease in tropical regions |
| 1. | 0.8 and 1.0 million |
| 2. | 1.0 and 1.2 million |
| 3. | 1.5 and 1.7 million |
| 4. | 7.0 and 8.0 million |