81. r-selection is characterized by-(1) Early sexual maturity (2) High parental care
    (3) Few offsprings (4) Large sized offsprings

Introduction

In the study of ecology and evolutionary biology, the concept of r-selection describes a strategy where species maximize their reproductive output in unpredictable or changing environments. This approach is fundamentally different from K-selection, where the emphasis is on survival and competitive ability. Understanding the traits that define r-selection is crucial for grasping how different organisms adapt to their habitats.

What Is r-Selection?

r-Selection refers to a reproductive strategy focused on producing many offspring quickly, with little investment in each. This strategy is favored in environments where resources are abundant for short periods, and population densities fluctuate widely.

Key Characteristics of r-Selection

Let’s examine the options and see which trait best defines r-selection:

(1) Early Sexual Maturity

• Correct!

• r-selected species reach reproductive age quickly, allowing them to take advantage of favorable conditions as soon as they arise.

• Early sexual maturity means these species can produce multiple generations in a short time, rapidly increasing their population when resources are available.

(2) High Parental Care

• Incorrect.

• r-selected species typically provide minimal or no parental care. Their strategy is to produce many offspring and rely on sheer numbers for survival, rather than investing in the care of each individual.

(3) Few Offspring

• Incorrect.

• The hallmark of r-selection is many offspring, not few. Producing large numbers increases the chances that some will survive unpredictable conditions.

(4) Large Sized Offspring

• Incorrect.

• r-selected species generally have small-sized offspring. This allows them to produce more individuals with the same amount of energy.

Examples of r-Selected Species

• Insects: Mosquitoes, fruit flies, and aphids, which mature quickly and lay hundreds of eggs.

• Annual plants: Weeds and grasses that germinate, grow, and reproduce rapidly.

• Small rodents: Mice and voles, which reach maturity in weeks and have large litters.

Why Early Sexual Maturity Matters

Early sexual maturity enables r-selected species to:

• Rapidly exploit temporary resources.

• Outpace competitors in colonizing new or disturbed habitats.

• Survive in environments where mortality rates are high and unpredictable.

r-Selection vs. K-Selection: A Quick Comparison

Conclusion

r-Selection is characterized by early sexual maturity, enabling species to reproduce quickly and in large numbers. This strategy is ideal for unstable or unpredictable environments, where the ability to rapidly increase population size is more advantageous than investing heavily in each offspring.

Correct answer:
(1) Early sexual maturity