83. Among the following which statement is false about r- selected species-
    (1) Long generation time (2) Many offspring
    (3) Short life cycle (4) Tendency to disperse

Introduction

In ecology, r-selected species are known for their rapid reproduction, short lifespans, and ability to thrive in unpredictable environments. These organisms adopt a “quantity over quality” approach to reproduction, producing many small offspring with minimal parental investment. However, not every reproductive strategy fits the r-selection model. Let’s identify which trait is not characteristic of r-selected species and understand why.

Core Traits of r-Selected Species

r-Selected species exhibit a suite of traits that help them exploit unstable or disturbed habitats:

• Early sexual maturity: They reproduce at a young age, allowing rapid population growth.

• Short life span: Most r-selected species live fast and die young, focusing on quick reproduction.

• Small size of offspring: Producing many small offspring increases the odds that some will survive unpredictable conditions.

• High fecundity: They lay or spawn many eggs or offspring at once, rather than investing heavily in each one.

• Little to no parental care: Offspring are often independent from birth and receive minimal support from parents.

• Rapid population growth: When conditions are right, populations can increase exponentially.

• Tendency to disperse: Offspring often spread widely to colonize new or disturbed habitats.

What Is Iteroparity?

Iteroparity is the reproductive strategy of producing offspring multiple times over a lifetime. This contrasts with semelparity, where an organism reproduces once in a massive burst and then dies.

Which Trait Is NOT Typical of r-Selected Species?

Let’s review the options:

1. Early sexual maturity — Typical of r-selected species.

2. Short life span — Typical of r-selected species.

3. Small size of offspring — Typical of r-selected species.

4. Iteroparity — NOT typical of r-selected species.

Why Iteroparity Is Not Typical

• Most r-selected species are semelparous, reproducing once in a large burst before dying. This is common in many insects, annual plants, and some fish.

• Iteroparity is more characteristic of K-selected species, which invest in fewer, larger offspring over multiple reproductive events, often with more parental care and longer lifespans.

Examples

• r-Selected, Semelparous: Many insects (e.g., mayflies), annual plants, some fish (e.g., Pacific salmon).

• K-Selected, Iteroparous: Elephants, humans, many birds and mammals.

Quick Comparison Table

Conclusion

Iteroparity is NOT a characteristic of r-selected species. While r-selected organisms focus on rapid, high-volume reproduction—often in a single, explosive event—iteroparity is more typical of K-selected species that reproduce multiple times and invest more in each offspring.

Correct answer:
(4) Iteroparity