The Mystery of the Celibate Rotifer

  1. What is a bdelloid rotifer?
  1. What is meant by ‘ancient asexual?’
  1. Describe how mutation rates can prove that rotifers are ‘ancient asexuals.’ What other evidence exists that bdelloids are asexual?
  1. What happens to most species that ‘give up’ sex for cloning?
  1. What are the advantages/disadvantages to sex?
  1. Describe the Red Queen hypothesis that explains why ancient asexuals are rare among eukaryotes.
  1. What happens when the rotifers are exposed to fungi?
  1. How to rotifers escape the fungus? How do rotifers travel from habitat to habitat?

Reading Questions: “Wholly Virgin” from Dr. Tatiana’s Sex Advice to All Creation

  1. What distinguishes viruses, bacteria, and eukaryotes?
  1. What provides genetic variation for eukaryotes, in terms of reproduction? Explain the analogy the author uses concerning a deck of cards.
  1. Elaborate on the Red Queen hypothesis that explains why ancient asexuals are rare among eukaryotes.
  1. What are the ‘ratchet’ and the ‘hatchet,’ as they relate to mutations?
  1. What are the evolutionary disadvantages of being asexual (as a species)? What are the evolutionary advantages of being sexual (as a species)?
  1. How does reproduction relate to infectious disease?
  1. Are males necessary? Is sex necessary?
  2. Come up with at least FOUR bullet-point statements for and against males/sex from an evolutionary perspective.(We will be discussing/debating this as a class!)

The Meaning of Sex: Genes and Gender

sections 27-30 – 38:23-48:23

  1. Why is sex good in an evolutionary sense?
  1. In determining if males are necessary, what two scenarios is the presenter comparing?
  1. What is the gender composition of species that clone?
  1. What do the fruits and vegetables represent?
  1. What are the rules of the simulation?
  1. What fraction of genes do clonally reproducing species pass to their offspring? What fraction of genes do sexually reproducing species pass to their offspring?
  1. Who ‘wins’ in the first generation?
  1. What creates diversity and the ‘raw material’ for evolution?
  1. What does swapping the banana for oranges and the apples for lettuce represent?
  1. What do most mutations do? What does the wilted lettuce represent? The rotting bananas?
  1. After swapping in deleterious mutations, which group ‘wins’ – the clonal reproducers or sexual reproducers?
  1. What is the benefit of sex and meiosis? What is the evolutionary purpose of males?