Read the overview on the concept of speciation and the difference between microevolution and macroevolution
Defining species
1. What is the definition of species?
2. What is the biological species concept?
3. Understand the term reproductive isolation, and how this happens due to pre zygotic and post zygotic barriers. Learn about the different mechanism which do not allow members of different species to interbreed. Study the examples under each category to gain a better understanding.
4. What are the limitations of the biological species concept? For eg, we cannot learn anything about species when studying fossils or asexually reproducing organisms.
5. What are some other definitions of species? Read about the morphological, ecological and phylogenetic species concept and how are they different from the biological species concept?
Allopatric and sympatric speciation
1. How are species formed? Is geographic separation necessary for the same?
2. Read about allopatric and sympatric speciation and how speciation occurs in both instances. What is the evidence for allopatric speciation? Read about the example of the species of snapping shrimp.
3. How does sympatric speciation occur? Learn how polyploidy, habitat differentiation and sexual selection play a role.
4. Of the two speciation events, which is more common and why?
Hybrids and Hybrid zones
1. What are hybrids? Read about the hybrid zone which is a region when members of different species and produce offspring. Learn about the hybrid zone and how the hybrids behave
2. Can the hybrids reproduce successfully? What are some example?
Speciation timeline
1. How long does it take for new species to form?
2. Understand how fossil remains give us a clue about how speciation occurs. What is the difference between punctuated model and the gradual model?
3. Reproductive isolation can also be influenced by genes or a single gene. Learn how a single gene influences the way in which the shells of Japanese snail spiral in different directions preventing mating
Genes, genomes and evolution
1. What can we learn from comparing genomes of widely divergent species?
2. What can we learn from comparing genomes of closely related species?
3. From the comparisons above, which genomes do you expect to be more similar?
4. What is the comparison of developmental processes of different multicellular organisms called?
5. What are homeotic genes?
6. What can we conclude about homeotic genes based on the fact that they are present in almost identical sequence in species ranging from fruit flies to mammals?