Problem 4 - Campbell Biology Concepts & Connections

Question

According to the biological species concept, species are defined by their a. particular roles in a biological community. b. ability to interbreed and produce viable, fertile offspring. c. reproductive isolation from nearby populations. d. common ancestry.

Step-by-Step Solution

Answer

b. ability to interbreed and produce viable, fertile offspring.

Step 1: Understanding the Question

Read the question carefully to understand what is being asked. The question is asking about the definition of a species according to the biological species concept.

Step 2: Reviewing the Biological Species Concept

The biological species concept defines species based on their ability to interbreed and produce viable, fertile offspring. This concept emphasizes the significance of reproductive isolation.

Step 3: Analyzing the Answer Choices

Look at each of the answer choices individually to determine which one aligns with the biological species concept.a. Particular roles in a biological community do not define species by the biological species concept.b. The ability to interbreed and produce viable, fertile offspring aligns with the biological species concept.c. Reproductive isolation is related but not the primary definition according to this concept.d. Common ancestry is more related to phylogenetic definitions of species.

Step 4: Selecting the Correct Answer

Based on the analysis, the answer that best fits the biological species concept is:b. ability to interbreed and produce viable, fertile offspring.

Key Concepts

reproductive isolation

Reproductive isolation is a key aspect of the biological species concept. It refers to the mechanisms that prevent different species from interbreeding. These mechanisms can be:

• Prezygotic isolation, which happens before fertilization occurs. Examples include different mating seasons or behaviors, and physical incompatibilities.
• Postzygotic isolation occurs after fertilization. This might include hybrid inviability or infertility, where the offspring are either not viable or sterile.

These barriers ensure that gene flow is restricted between different species, maintaining distinct species lines.

viable offspring

For a species to fit within the biological species concept, members must reproduce and produce viable offspring. Viable offspring are those that are healthy and capable of surviving to adulthood, ensuring the continuation of the species. This means that the offspring must:

• Be able to develop properly through all life stages.
• Possess the capability to reproduce themselves, ensuring fertility.

If the offspring are sterile, such as in the case of a mule (a hybrid of a horse and a donkey), the parent organisms are considered different species.

species definition

The definition of a species under the biological species concept is based on the ability of organisms to interbreed and produce viable, fertile offspring. This concept focuses more on:

• Genetic exchange between individuals.
• The natural reproductive behavior among populations.

This definition helps distinguish species by their reproductive compatibility rather than their physical characteristics or roles in the ecosystem. It's crucial for understanding biodiversity and the evolutionary relationships among species.

interbreeding

Interbreeding is a critical factor in defining species by the biological species concept. It involves:

• The capability of individuals from the same species to mate and produce offspring.
• The sharing of genetic material within a species.

Interbreeding ensures that the genetic pool is maintained and allows for genetic variability which is essential for the adaptability and survival of the species. The lack of interbreeding between different species maintains their distinct identities.