Struggle for existence

Definition

The struggle for existence refers to the competition among individuals and species for limited resources, which is a fundamental concept in natural selection theory. This struggle influences the survival and reproductive success of organisms, shaping the evolutionary process. As populations grow, the demand for resources such as food, space, and mates increases, leading to competition that drives adaptation and evolution.

5 Must Know Facts For Your Next Test

1. The struggle for existence is not solely a physical battle; it includes competition for resources, mates, and habitat, as well as avoidance of predation.
2. This concept was prominently discussed by Charles Darwin, who emphasized that those organisms better adapted to their environment have higher chances of survival.
3. Population growth often exceeds resource availability, intensifying the struggle for existence and resulting in natural selection.
4. The struggle can lead to various outcomes, including survival of the fittest, extinction of less competitive species, and evolutionary changes in species over time.
5. Human activities, like habitat destruction and climate change, can exacerbate the struggle for existence by further limiting resources available to various species.

Review Questions

• How does the struggle for existence contribute to the process of natural selection?
  • The struggle for existence is a driving force behind natural selection as it creates competition among individuals for scarce resources. Organisms that possess advantageous traits are more likely to survive and reproduce in this competitive environment. Over time, these beneficial traits become more common in the population, illustrating how the struggle directly influences evolutionary changes.
• Discuss how environmental factors can affect the struggle for existence within a population.
  • Environmental factors such as climate change, availability of food, and habitat destruction can significantly impact the struggle for existence. For example, if a drought reduces food supply in an ecosystem, competition among individuals increases as they vie for limited resources. This heightened competition can lead to higher mortality rates among less adapted individuals and promote natural selection favoring those with traits better suited for survival under new conditions.
• Evaluate the implications of human-induced changes on the struggle for existence in various species.
  • Human-induced changes such as urbanization, pollution, and climate change have profound effects on the struggle for existence across species. These changes often disrupt natural habitats and deplete essential resources, intensifying competition among organisms. As certain species adapt or become extinct due to these pressures, it alters ecological balances and can lead to a loss of biodiversity. Understanding these implications emphasizes the interconnectedness of human activity and ecological health.

Related terms

Natural Selection:

The process by which individuals with advantageous traits are more likely to survive and reproduce, leading to a gradual change in the population over generations.

Carrying Capacity: The maximum population size that an environment can sustain indefinitely without degrading the habitat.

Adaptive Radiation:

The diversification of a group of organisms into forms filling different ecological niches, often following a period of environmental change or the colonization of new habitats.