One characteristic that distinguishes a population in an extinction vortex from most other populations is that a. it is a rare, top-level predator. b, its effective population size is lower than its total population size. c. its genetic diversity is very low. d. it is not well adapted to edge conditions.

Verified step by step guidance

1. Understand the term 'extinction vortex': An extinction vortex is a process where a population's size and genetic diversity decrease, leading to a greater likelihood of extinction.
2. Analyze the options: Option (b) mentions effective population size, which is a key concept in understanding population genetics and the extinction vortex.
3. Recall the definition of effective population size: Effective population size is the number of individuals in a population who contribute offspring to the next generation, which is usually lower than the total population size.
4. Connect effective population size to extinction vortex: A lower effective population size means fewer genetic variations are passed on, which can lead to inbreeding and an increased risk of extinction.
5. Conclude the correct answer: Option (b) 'its effective population size is lower than its total population size' directly relates to the concept of an extinction vortex and is the distinguishing characteristic of such populations.

Key Concepts

Extinction Vortex

An extinction vortex is a phenomenon where a population experiences a downward spiral towards extinction due to a combination of factors such as reduced genetic diversity, inbreeding, and environmental pressures. As populations shrink, their ability to adapt to changes diminishes, leading to further declines. This concept is crucial for understanding how small populations can become trapped in a cycle that accelerates their extinction risk.

Effective Population Size

Effective population size (Ne) refers to the number of individuals in a population who contribute offspring to the next generation, which is often lower than the actual population size due to factors like unequal sex ratios or variation in reproductive success. A lower effective population size can lead to increased inbreeding and loss of genetic diversity, making populations more vulnerable to extinction.

Genetic Diversity

Genetic diversity is the total number of genetic characteristics in the genetic makeup of a species. High genetic diversity allows populations to adapt to changing environments and resist diseases, while low genetic diversity can lead to inbreeding depression and reduced resilience. In the context of extinction vortices, low genetic diversity is a critical factor that exacerbates the risk of extinction.