The rate at which new born individuals are joining the population by reproduction is known as:
1) natality
2) mortality
3) Fertility
4) Vitality

Options

A. natality
B. mortality
C. Fertiliy
D. Vitality

Answer

To solve the question regarding the rate at which newborn individuals are joining the population by reproduction, we will analyze each of the provided options step by step.

### Step 1: Understand the term "natality"
- **Definition**: Natality refers to the birth rate in a population, which is the number of new individuals born over a specific time period.
- **Relevance**: Since the question specifically asks about newborn individuals joining the population through reproduction, this term is directly related.

**Hint**: Think about terms related to birth and reproduction when considering the options.

### Step 2: Analyze the term "mortality"
- **Definition**: Mortality is the death rate, which indicates the number of individuals that die in a population over a specific time period.
- **Relevance**: This term is the opposite of natality and does not pertain to the addition of newborns.

**Hint**: Consider what happens to individuals in a population when they die versus when they are born.

### Step 3: Evaluate the term "fertility"
- **Definition**: Fertility refers to the ability of individuals to reproduce and become pregnant.
- **Relevance**: While fertility is related to reproduction, it does not specifically measure the rate of newborns joining the population.

**Hint**: Focus on the difference between the ability to reproduce and the actual number of births.

### Step 4: Consider the term "vitality"
- **Definition**: Vitality is the capacity of an organism to live, grow, and develop. It reflects the overall health and energy of an individual.
- **Relevance**: This term does not relate to the rate of reproduction or the addition of newborns to a population.

**Hint**: Think about how vitality relates to life in general rather than specifically to reproduction.

### Conclusion
After analyzing all the options:
- The term that best describes the rate at which newborn individuals are joining the population by reproduction is **natality**.

Thus, the correct answer is **1) natality**.

---