Evidence for evolution - Comparative Anatomy Flashcards
What is comparative anatomy?
Is the study of the similarities and differences in structure between different organisms.
What are structural features also called?
Morphological features.
What is embryology?
Is the study of the anatomy of embryos and how they develop over time until the adult stage.
What is comparative embryology?
Is used to establish evolutionary relationships and common ancestry. Some vertebrates possess traits that are present in the embryos but not in adults. These traits had a function in ancestors, but do not have one in the adult stage of organisms. Therefore comparative embryology suggests they all share a common ancestor.
What are 5 characteristics that vertebrae embryos share?
- Pharyngeal slits
- Absence of paired appendages
- Well-developed post-anal tail
- Two-chambered heart
- Similiar levels of brain development
What are vestigial structures?
A structure that during the course of evolution, has been reduced in size or has lost its function.
What are homologous structures?
A feature with a similar structure but different function in different organisms. Homologous structures are a form of divergent evolution, as these structures show divergence over time to better suit their environment.
What is an example of homologous structures?
The pentadactyl limb and the bones in the forearm.
What are analogous structures?
Are different structures with the same function. Analogous structures are a form of convergent evolution in which organisms evolve independently.
What is an example of analogous structures?
The wing of a bat, bird and insects.
What is divergent evolution?
Is when populations of a species differentiate to become separate species.
What is convergent evolution?
Occurs when spieces that are not closely related independently develop similar adaptations to their environment.
