Exam 4 Essay Help

Explain specifically five agents that can bring about change in the allele frequencies in a population of fish.  Be sure that you site specific evidence and examples. 

The strength of this essay depends on the specific examples for each of the 5 agents of microevolution.  Explicitly connecting evolution to changes in allele frequencies is a must for this essay.

Using a population of pollenpepper birds, explain and illustrate how new species could arise from the original population.  Be sure to be explicit and site specific mechanisms.  A minimum of 5 specific means will need to be identified.   A discussion of whether speciation could/would occur slow or rapidly is also necessary.

The strength of your essay depends on your ability to clearly articulate how new species can arise and whether or not speciation occurs rapidly or slowly (citing specific information).

What role does sex have in biology (specifically evolutionary biology)?  Using three specific examples, discuss the role sex (sexual selection) has in evolution.

The strength of your essay depends on your ability to clearly articulate how sexual selectin operates to drive evolution.

• Flashy Fish (lab 9): male fish have to be attractive enough to mate, but not too attractive or they get eaten.

• Why Sex? (video)

  • Evolutionary importance of sex.  Why did it evolve?

  • Female only lizards: pros and cons

  • Red Queen Theory (what happens when a species stops evolving?)

  • Sexual selection: peacock's tail, bird songs

  • Sexual dimorphism.

  • Advantages and disadvantages of sexual v. asexual reproduction (from an evolutionary perspective).

Discuss three of life’s ‘great transformations’ to illustrate how evolution operates. 

The strength of this essay depends on your ability to explain what a ‘great transformation’ is in evolutionary biology by using three examples.

• Events from Earth's Timeline activity.  Could include: cyanobacteria (blue-green bacteria) generating oxygen, formation of ozone, Cretaceous Extinction.

• Great Transformations (video)

  • The Tree of Life stretches back over 4 billion years.

  • Whale evolution as an example of how species transition (change)

  • Transition from water to land.  Hint: include information from chapter 19 (amniotic egg, lungs, etc.). 

  • The Cambrian Explosion

  • Human Evolution

What is an evolutionary arms race?  Using three specific examples, explain how and why evolutionary arms races occur.

The strength of your essay depends on your ability to clearly articulate what an evolutionary arms race is using specific examples. 

• Abstract 9 (bacterial resistance to antibiotics).

• Evolutionary Arms Race (video)

  • Newts and snake: ramping up toxicity and resistance

  • Predators v. Prey (faster legs v. sharper teeth).

  • Leaf cutter Ants of the Amazon (co-evolution against pests)