You are a scientist presenting information selection. Provide A justification to support the claim that environmental changes cause changes in populations of organisms. (explain the science of WHY)

Answer 1

One of the fundamental concepts in biology is that of natural selection, which explains how populations of organisms adapt and evolve over time in response to changes in their environment. Organisms that are better suited to their environment have a higher chance of survival and reproduction, leading to an increase in their population. Here is the science behind why environmental changes are known to cause changes in populations of organisms:

1. Selective Pressure: Environmental changes can create new selective pressures on organisms, meaning certain traits become more advantageous or disadvantageous for survival and reproduction. For example, the availability of food sources, temperature, water availability, or presence of predators can all exert selective pressures on a population.

2. Genetic Variation: Within any population, there is genetic variation, which refers to the range of different genetic traits within the individuals of a species. Environmental changes can favor certain traits within this genetic variation, driving changes in the population. For example, if a sudden increase in temperature occurs, individuals possessing genetic traits that allow them to tolerate higher temperatures (such as protective pigmentation or heat-resistant enzymes) may have a greater chance of surviving and reproducing, leading to an increase in their population.

3. Survival and Reproduction: The ultimate driving force for changes in population is the ability of individuals to survive and reproduce in their environment. Individuals with traits that enhance their ability to survive, find mates, obtain resources, and successfully reproduce are more likely to pass on their genes to the next generation, causing a shift in the genetic composition of the population.

4. Evolutionary Adaptation: Over time, repeated environmental changes can lead to the accumulation of favorable traits within populations, resulting in adaptive evolution. This process occurs through natural selection acting on genetic variation, leading to the development of new adaptations in organisms. For example, long-term exposure to low light conditions can lead to the development of larger eyes or enhanced visual sensitivity in certain species.

5. Differential Survival and Reproduction: Environmental changes create different conditions for organisms, resulting in differential survival and reproduction. Individuals with traits that are well-suited to the new environment are more likely to survive and reproduce successfully, passing on their advantageous traits to the next generation. Gradually, the population begins to exhibit traits that are better adapted to the changed environment.

Overall, the connection between environmental changes and changes in populations of organisms lies in the process of natural selection, where certain traits become favored or disadvantaged due to the selective pressures imposed by the changing environment. By understanding this scientific concept, we can appreciate how environmental changes drive changes in the composition and characteristics of populations over time.