Lecture on Speciation and Evolutionary Development (8)

This set of flashcards covers key concepts and definitions related to speciation, evolutionary development, and the role of genes in these processes.

What is sympatric speciation?

A form of speciation that occurs when populations evolve to become distinct species while living in the same geographic area.

Why is sympatric speciation considered to be uncommon?

It is thought to be uncommon because it typically requires mechanisms that isolate populations within the same environment, which are rare.

What is polyploid speciation?

A form of speciation that involves the duplication of the entire set of chromosomes, leading to new species.

How does polyploid speciation occur?

It often occurs due to errors in meiosis or mitosis, resulting in organisms with multiple sets of chromosomes.

Describe an example of polyploid speciation.

An example can be found in Chamerion (fireweed), where polyploidy has led to the formation of new species.

Why are Cichlid fish in Lake Apoyo considered a unique case?

They are a good example of sympatric speciation due to their rapid diversification and adaptive radiation in a single lake.

What are the goals of the field of Evolution and Development (EvoDevo)?

To understand the relationship between development processes and evolutionary changes.

Define allometry in EvoDevo.

The study of the relationship between the size of an organism and the shape of its body parts.

What does heterochrony describe?

It describes changes in the timing of developmental events, leading to changes in size and shape.

What is pedomorphosis?

It is the retention of juvenile features in the adult stage of an organism.

Define heteromorphy.

It refers to the occurrence of different forms in adult organisms related to their developmental processes.

What is modularity in the context of EvoDevo?

The concept that development can occur in distinct, semi-independent units or modules.

What are homeotic genes?

Genes that regulate the development of anatomical structures in various organisms.

What are HOX genes?

Homologous homeotic genes that play a crucial role in determining the body plan of vertebrates.

What are transcription factors?

Proteins that help regulate the expression of specific genes by binding to nearby DNA.

What is the purpose of gene knockouts in EvoDevo research?

Gene knockouts are used to determine the function of specific genes by observing the effects of their absence.

What are labelled antibodies used for in EvoDevo research?

They are used to detect specific proteins or antigens in tissues to study gene expression.

What similarities exist between HOX (HOM) genes in insects and vertebrates?

Both share homologous structures and functions, indicating a common ancestor and conserved developmental processes.

When did the HOX gene pattern of effects on development evolve?

The HOX gene pattern evolved during early metazoan evolution.

Describe key points in the evolution of HOX genes.

Key points include the expansion of the gene family through duplication events and the conservation of gene function across species.

How do HOX genes control leg development in arthropods?

HOX genes provide positional information that determines the identity and development of leg segments in arthropods.

What are MADS-Box genes?

A group of genes that play a crucial role in flower development and the formation of floral organs.

What is the ABC model in flower development?

A model that explains how the combination of three classes of genes determines the identity of floral organs, discovered through genetic studies.