In population ecology, what is meant by population density?

• A. The number of individuals of a species per unit area or per unit volume
• B. The rate at which individuals enter a population through births and immigration
• C. The total number of individuals of a species in a given region (population size)
• D. The pattern of spacing of individuals within a population (dispersion)

Answer: (A)

Verified step by step guidance

1. Understand that population density refers to how many individuals of a species are found in a specific area or volume, which helps ecologists understand how crowded or spread out a population is.
2. Recognize that population density is calculated by dividing the total number of individuals in the population by the area (for terrestrial organisms) or volume (for aquatic organisms) they occupy.
3. Express this relationship mathematically as: \(\text{Population Density} = \frac{\text{Number of Individuals}}{\text{Unit Area or Volume}}\).
4. Differentiate population density from related concepts such as population size (total number of individuals), population growth rate (births and immigration), and dispersion (spacing patterns), which are distinct ecological terms.
5. Conclude that population density specifically measures the concentration of individuals in a given space, making it a key parameter in studying population ecology.