In general , species diversity ....ae we move away from the equator towards the poles and with very few exceptions, tropics harbor .... species than temperature or polar areas.

Options

A. a -increases , b-less
B. a -decreases , b-more
C. a -increases , b-more
D. a -decreases, b- less

Answer

To solve the question regarding species diversity as we move from the equator towards the poles, we can break it down into two parts:

### Step-by-Step Solution:

1. **Understanding Species Diversity**:
- Species diversity refers to the variety of different species within a given ecosystem or geographical area. It is influenced by various factors including climate, geography, and available resources.

2. **Effect of Latitude on Species Diversity**:
- As we move from the equator towards the poles, the amount of sunlight and warmth decreases. The equator receives direct sunlight year-round, which supports a wide variety of plant and animal life.
- In contrast, polar regions receive less sunlight and have harsher climates, which limits the types of species that can thrive there.

3. **Filling in the First Blank**:
- The question asks how species diversity changes as we move away from the equator.
- Based on the understanding that species diversity decreases with increasing latitude, we can fill in the first blank with "decreases".

4. **Tropical Regions vs. Temperate and Polar Areas**:
- The second part of the question states that the tropics harbor a certain number of species compared to temperate or polar areas.
- Given that tropical regions have a warmer climate and more sunlight, they generally support a greater diversity of species compared to temperate or polar regions.

5. **Filling in the Second Blank**:
- Therefore, we can fill in the second blank with "more", indicating that the tropics harbor more species than temperate or polar areas.

6. **Final Answer**:
- The complete statement would read: "In general, species diversity decreases as we move away from the equator towards the poles, and with very few exceptions, tropics harbor more species than temperate or polar areas."