Extinction selectivity

Definition

Extinction selectivity refers to the concept that certain species are more likely to go extinct than others during mass extinction events or periods of environmental change. This selectivity is influenced by various factors, such as species traits, ecological roles, and environmental conditions. Understanding extinction selectivity is crucial for interpreting macroevolutionary patterns and processes as it sheds light on how different groups respond to environmental stressors over geological time scales.

5 Must Know Facts For Your Next Test

1. Extinction selectivity can be influenced by factors such as body size, reproductive rate, and ecological specialization, making some species more vulnerable than others.
2. During mass extinctions, it has been observed that marine organisms, like corals and mollusks, often exhibit different patterns of selectivity compared to terrestrial species.
3. Extinction selectivity can lead to significant shifts in community structure and biodiversity following a mass extinction event.
4. The Late Permian and Cretaceous-Paleogene extinctions are two well-studied examples where extinction selectivity played a critical role in determining which species survived and which went extinct.
5. Understanding extinction selectivity helps paleobiologists make predictions about future biodiversity trends in the face of ongoing environmental changes due to human activity.

Review Questions

• How does extinction selectivity help explain the varying survival rates of different species during mass extinction events?
  • Extinction selectivity helps explain survival rates by highlighting that not all species are equally affected by mass extinctions. Certain traits, such as body size or reproductive strategies, can make some species more resilient or vulnerable to environmental changes. For instance, larger species may be more susceptible to extinction due to their longer generation times and lower reproductive rates. In contrast, smaller or more adaptable species might survive better, demonstrating how specific characteristics influence their chances during these critical events.
• Discuss the implications of extinction selectivity on the recovery of ecosystems after mass extinctions.
  • The implications of extinction selectivity on ecosystem recovery are significant. When certain species are selectively lost while others persist or thrive, the remaining organisms can reshape community dynamics and ecological interactions. For example, if a dominant predator goes extinct while its prey survives, this can lead to population explosions in prey species, altering vegetation patterns and overall biodiversity. Additionally, the loss of specific functional groups can hinder ecosystem recovery by disrupting established roles in nutrient cycling and energy flow.
• Evaluate how studying extinction selectivity in past events can inform our understanding of current biodiversity loss and conservation efforts.
  • Studying extinction selectivity in past events provides valuable insights into which traits may confer resilience or vulnerability to species facing contemporary threats. By examining historical patterns of survival and extinction, conservationists can identify critical characteristics that promote biodiversity stability. This understanding can guide targeted conservation strategies that prioritize protecting vulnerable species with less adaptive capacity. Furthermore, insights gained from past extinctions can help predict potential outcomes of current environmental changes, informing policies aimed at mitigating biodiversity loss in today's rapidly changing world.

Related terms

mass extinction:

A mass extinction is a significant and rapid decrease in the diversity and abundance of life on Earth, characterized by the widespread extinction of numerous species across various taxa.

biodiversity:

Biodiversity refers to the variety of life forms within a given ecosystem or on Earth as a whole, including the diversity of species, genetic variations, and ecological interactions.

niche: A niche is the role or function of an organism or species within an ecosystem, encompassing its habitat, resource use, and interactions with other organisms.