Loading...

BIO310: Developmental Biology

Unit 8: "Evo-Devo": Evolutionary and Developmental Biology   Do all organisms share common ancestors?  Why are there so many kinds of organisms?  Why are there not more kinds of organisms?  Do we have traits in common with other closely related species, or even with very distantly related species?  How did dramatic evolutionary changes occur?
          
Developmental biology can help us answer many basic evolutionary questions.  In fact, developmental evidence has provided support for Darwin’s theory of evolution and in fact continues to illuminate some of the practical questions involved.  The developmental similarities animals share, from the “housekeeping” genes we have in common with fruit-flies to the homologous limb structures we share with all other vertebrates, demonstrate our relatedness.  The mechanisms through which developmental changes occur give us an idea of how even minor alterations in gene patterning during development could lead to the expression of very different traits for natural selection to act on.  The practical constraints on development explain why there are restrictions on the amount of evolutionary variation that can exist.  The combination of insights in evolutionary biology and developmental biology can help us answer questions in both fields.

Unit8 Learning Outcomes
Upon successful completion of this unit, students will be able to:

  • Answer questions about the evidence developmental biology has provided for evolution and how various evolutionary processes came about.
  • Demonstrate an understanding of the function of HOX genes and their importance in evolutionary processes.
  • Demonstrate an understanding of developmental constraints as they relate to what evolutionary adaptations/changes are possible.
  • Demonstrate an understanding of the role that modularity had played in evolution.

8.1 Darwin, Evolution, and Developmental Evidence   - Reading: The National Institutes of Health: Professor Scott Gilbert’s Developmental Biology: “’Unity of Type’ and ‘Conditions of Existence’” Link: The National Institutes of Health: Professor Scott Gilbert’s Developmental Biology: “’Unity of Type’ and ‘Conditions of Existence’” (HTML)
 
Instructions: Read this section in its entirety along with all associated figures (Figs. 22.1-22.2).
 
Terms of Use: Please respect the copyright and terms of use displayed on the webpage above.

  • Web Media: PBS: Nova’s Evolution: “The Zoo of You” and “Guess the Embryo” Links: PBS: Nova’s Evolution: “The Zoo of You” (HTML) and “Guess the Embryo” (HTML)
     
    Instructions: Go through these interactive sites that demonstrate the ways in which various human traits and developmental processes relate back to our evolutionary ancestors and show the similarities in embryos across phyla. These will cover the material in 8.1-8.3.
     
    Terms of Use: Please respect the copyright and terms of use displayed on the webpage above.

8.2 HOX Genes   - Reading: The National Institutes of Health: Professor Scott Gilbert’s Developmental Biology: “Hox Genes: Descent with Modification” Link: The National Institutes of Health: Professor Scott Gilbert’s Developmental Biology: “Hox Genes: Descent with Modification” (HTML)
 
Instructions: Read this section in its entirety along with all associated figures (Figs. 22.3-22.11). This will cover the material in 8.2.
 
Terms of Use: Please respect the copyright and terms of use displayed on the webpage above.

8.2.1 Changes in Downstream Genes   8.2.2 Changes in Expression within Body Segments   8.2.3 Changes in Expression between Body Segments   8.2.4 Changes in Gene Number   8.3 Homology   - Reading: The National Institutes of Health: Professor Scott Gilbert’s Developmental Biology: “Homologous Pathways of Development” and “Generating the Proximal-Distal Axis” Link: The National Institutes of Health: Professor Scott Gilbert’s Developmental Biology: “Homologous Pathways of Development” (HTML) and “Generating the Proximal-Distal Axis” (HTML)
 
Instructions: Read all of “Homologous Pathways” along with all associated figures (Figs. 22.12-22.16), and in “Generating the Proximal-Distal Axis,” scroll down to read the grey text box “Hox Genes and the Evolution of the Tetrapod Limb.”
 
Terms of Use: Please respect the copyright and terms of use displayed on the webpage above.

8.4 Modularity   - Reading: The National Institutes of Health: Professor Scott Gilbert’s Developmental Biology: “Modularity: The Prerequisite for Evolution through Development” Link: The National Institutes of Health: Professor Scott Gilbert’s Developmental Biology: “Modularity: The Prerequisite for Evolution through Development” (HTML)
 
Instructions: Read this section in its entirety along with all associated figures (Figs. 22.17-22.22). This will cover the material in 8.4.1-8.4.3.
 
Terms of Use: Please respect the copyright and terms of use displayed on the webpage above.

8.4.1 Dissociation   8.4.2 Duplication and Divergence   8.4.3 Co-option   8.4.4 Correlated Progression   - Reading: The National Institutes of Health: Professor Scott Gilbert’s Developmental Biology: “Developmental Correlation” Link: The National Institutes of Health: Professor Scott Gilbert’s Developmental Biology: “Developmental Correlation” (HTML)
 
Instructions: Read the subsection on “Correlated Progression.”

 Terms of Use: Please respect the copyright and terms of use
displayed on the webpage above.

8.5 Developmental Constraints   - Reading: The National Institutes of Health: Professor Scott Gilbert’s Developmental Biology: “Developmental Constraints” Link: The National Institutes of Health: Professor Scott Gilbert’s Developmental Biology: “Developmental Constraints” (HTML)
 
Instructions: Read this section in its entirety along with all associated figures (Figs. 22.26-22.27).  This will cover the material in 8.5.
 
Terms of Use: Please respect the copyright and terms of use displayed on the webpage above.

8.5.1 Physical   8.5.2 Morphogenetic   8.5.3 Phyletic   8.6 Developmental Evolutionary Biology   - Reading: The National Institutes of Health: Professor Scott Gilbert’s Developmental Biology: “A New Evolutionary Synthesis” Link: The National Institutes of Health: Professor Scott Gilbert’s Developmental Biology: “A New Evolutionary Synthesis” (HTML)
 
Instructions: Read this section in its entirety.
 
Terms of Use: Please respect the copyright and terms of use displayed on the webpage above.