GROUP PROJECT: NATURAL SELECTION

							 GROUP PROJECT:
NATURAL SELECTION
 Chris Ming and Drew “Gary” Hall
              Introduction
 Our goal was to, in a relatively short period
 of time, see to it that students would gain a
 basic understanding of Darwin’s theory of
 evolution by natural selection.
                   Objectives
   Students should be able to demonstrate and
    apply knowledge of natural selection by:

   1. Explaining how new species of an animal may
    develop, e.g., Galapogos finches with
    differentiated beaks.

   2. Explaining the development of bacterial
    resistance to antibiotics.
    Pretest Misconceptions – Task 1
 1. Several students had the right idea that there
  were niches to which some animals were better
  adapted. Such animals (finches) would adapt to
  fit a niche and be able to eat more effectively or
  whatnot.
 2. A lot of students just threw out the term
  “evolution”, meaning they didn’t know what was
  really involved.
 3. Pangaea/tectonics – but might show age
 4. Several students suggested that breeding
  between finches created offspring of a new beak
  type/species.
  Pretest Conclusions – Task 1
 Some   students know that over time
  species can adapt to better fit their
  environments – but they don’t know the
  “mechanism” for this.
 Many students have erroneous beliefs of
  how speciation and adaptation occurs.
 They know somewhat that this takes a
  long time (Pangaea, tectonics, etc.)
  Pretest misconceptions – Task 2
 Majority (26) said outside influences could
  change DNA, causing resistance.
 Many were split between thinking that
  DNA can change itself in response to the
  environment (6) and that mutation rates
  can fluctuate and increase during periods
  of mutation (8).
 Some were right-on (10): prior genetic
  differences are selected for or against.
  Pretest Conclusions – Task 2
 1.  Some students have a basic
  understanding of natural selection
  involving selection for/against prior genetic
  differences.
 2. BUT many think in Lamarckian or other
  mistaken ways, not taking into account
  prior genetic differences.
          Common Lessons
 1. Geologic time online activity (1 day)
 2. Evolution of the basketball shoe
 3. Natural selection: online activity (1 day)
           Posttest Outcomes
 After the unit, approximately 75% of students
  met both objectives: (1) explaining how
  speciation happens, and (2) demonstrating a
  knowledge of selection on existing genetic
  differences.
 This was ~double from the pretest and
  preinterview results.
 The most dramatic improvements were on the
  second objective. At first, many students
  believed in self-change or bacterial
  “intelligence,” but they grew to understand that it
  is their prior genetic variation that matters.
      Comical Misconceptions 
   “Maybe the [Galapagos] islands broke off and floated
    away.”
   “Nuclear radiation” (with drawings of glowing lizards and
    dodo birds)
   “The volcanos may provide some kind of cell which kept
    multiplying until the birds were made. There were
    several types of cells so that is why there beaks are
    different.”
   “The presence of the 14 different types of finch species
    probably has to do with the first explorers of the island.
    When there were some types of birds there, they mated
    with them which made an even different species.”