Chapter 14: The Origin of Species

These flashcards cover the key concepts from Chapter 14 on the Origin of Species in the context of biological diversity.

What is microevolution?

Microevolution is the change in the gene pool of a population from one generation to the next.

What is speciation?

Speciation is the process by which one species splits into two or more species, accounting for the unity and diversity of life.

What is the biological species concept?

The biological species concept defines a species as a group of populations whose members can interbreed in nature and produce fertile offspring with each other but not with members of other species.

What emphasizes reproductive isolation?

The biological species concept emphasizes reproductive isolation.

What does the morphological species concept focus on?

The morphological species concept is based on observable physical traits.

How does the ecological species concept define a species?

The ecological species concept defines a species by its ecological niche, focusing on unique adaptations to particular roles in a biological community.

What is the phylogenetic species concept?

The phylogenetic species concept defines a species as the smallest group of individuals that share a common ancestor, forming one branch of the tree of life.

What are reproductive barriers?

Reproductive barriers serve to isolate the gene pools of species and prevent interbreeding.

What types of reproductive barriers exist?

Reproductive barriers are categorized as prezygotic (before zygotes form) and postzygotic (after zygotes form).

What is allopatric speciation?

Allopatric speciation occurs when geographic isolation leads to the separation of populations, ultimately resulting in speciation.

What can lead to the evolution of reproductive barriers?

Reproductive barriers can arise as populations diverge in response to different environmental factors.

What is sympatric speciation?

Sympatric speciation occurs when a new species arises within the same geographic area as its parent species, often due to factors like polyploidy or habitat differentiation.

How do hybrid zones relate to speciation?

Hybrid zones are regions where populations of different species meet and mate, potentially leading to reinforcement of reproductive barriers or fusion of species.

What is adaptive radiation?

Adaptive radiation is the evolution of many diverse species from a common ancestor, often observed in isolated environments like islands.

Why are isolated islands important for speciation?

Isolated islands provide opportunities for adaptive radiations due to repeated isolation, speciation, and recolonization events.

What key concept discusses the diversification of cichlids in Lake Victoria?

Sexual selection has played a significant role in the diversification of cichlids in Lake Victoria.

What is polyploidy?

Polyploidy is the duplication of the chromosome number due to errors in cell division, often leading to speciation in plants.

What happens in postzygotic barriers?

In postzygotic barriers, hybrid offspring are produced but may exhibit reduced viability, reduced fertility, or hybrid breakdown.