Figure 1: A biology worksheet activity where students calculate the population density of birds, frogs, and snakes within a 200 sqm area.

Problem Overview:

The task involves analyzing the distribution of three species (birds, frogs, and snakes) in a given area and calculating their population densities. The steps include:
1. Counting the total number of each species.
2. Calculating the population density using the formula:
\[
\text{Population Density} = \frac{\text{Number of Organisms}}{\text{Area (in square meters)}}
\]
3. Answering questions about the distribution patterns, differences in density, and the importance of knowing population density.

---

Step 1: Count the Total Number of Each Species

From the illustration:
- Birds (triangles): Count all the red triangles.
- Frogs (squares): Count all the blue squares.
- Snakes (circles): Count all the yellow circles.

#### Counting:
- Birds: There are 18 red triangles.
- Frogs: There are 40 blue squares.
- Snakes: There are 22 yellow circles.

---

Step 2: Calculate Population Density

The area is given as 200 sqm. Use the formula:
\[
\text{Population Density} = \frac{\text{Number of Organisms}}{\text{Area}}
\]

#### Calculations:
1. Birds:
\[
\text{Density of Birds} = \frac{18}{200} = 0.09 \, \text{birds per sqm}
\]

2. Frogs:
\[
\text{Density of Frogs} = \frac{40}{200} = 0.20 \, \text{frogs per sqm}
\]

3. Snakes:
\[
\text{Density of Snakes} = \frac{22}{200} = 0.11 \, \text{snakes per sqm}
\]

---

Step 3: Complete the Table

Using the counts and densities calculated above, fill in the table:

| Name of Species | Total Number | Density |
|-----------------|--------------|---------|
| birds | 18 | 0.09 |
| frogs | 40 | 0.20 |
| snakes | 22 | 0.11 |

---

Step 4: Answer the Questions

#### Question 1: How will you describe the distribution patterns of the organisms?
- Birds: Birds are scattered across the area but are not densely clustered. Their distribution appears somewhat random.
- Frogs: Frogs are the most numerous and appear to be more evenly distributed or slightly clustered in some areas.
- Snakes: Snakes are also scattered but less densely than frogs. Their distribution seems more dispersed compared to frogs.

#### Question 2: Identify the population with the greatest density? Which has the least density?
- Greatest Density: Frogs have the highest density at 0.20 frogs per sqm.
- Least Density: Birds have the lowest density at 0.09 birds per sqm.

#### Question 3: What do you think is the importance of knowing the population density of a species in a certain area?
- Knowing the population density helps in understanding the ecological health of an area. It provides insights into:
- Resource Availability: High density might indicate abundant resources, while low density might suggest scarcity.
- Habitat Suitability: Densities can help assess whether the habitat is suitable for a species.
- Conservation Efforts: Identifying areas with low densities can highlight regions needing conservation attention.
- Predator-Prey Dynamics: Population densities influence interactions between species.
- Human Impact: Monitoring changes in density over time can reveal the impact of human activities on wildlife.

#### Question 4: Why do you think there are differences in the population density?
- Differences in population density can be attributed to several factors:
- Habitat Preferences: Each species may prefer different microhabitats within the area. For example, frogs might thrive in wetter areas, while snakes might prefer drier spots.
- Food Availability: Species with higher densities might have more access to food resources.
- Reproductive Rates: Species with higher reproductive rates might have higher densities.
- Predation Pressure: Areas with fewer predators might support higher densities.
- Competition: Competition among species for resources can affect their respective densities.
- Environmental Factors: Temperature, humidity, and other environmental conditions can influence species distribution.

---

Final Answer:

\[
\boxed{
\begin{array}{|c|c|c|}
\hline
\text{Name of Species} & \text{Total Number} & \text{Density} \\
\hline
\text{birds} & 18 & 0.09 \\
\text{frogs} & 40 & 0.20 \\
\text{snakes} & 22 & 0.11 \\
\hline
\end{array}
}
\]