Sloths et al. teaching the "E" word:

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Sloths et al. teaching the "E" word

• using extant and extinct xenarthran cranial
  materials to exemplify for middle school students
  change though time and how science works

Barbara J. Shaw Luis A. Ruedas Portland State
University
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Acknowledgments
My Advisory Committee Dr. Debbie Duffield Dr.
Lisa Weasel Dr. Keith Hadley Dr. Virginia
Butler Dr. Randy Zelick (Comprehensive
Committee) Most of all Dr. Luis A. Ruedas, my
major professor, for all his invaluable support,
guidance, and encouragement Dr. Richard B.
Forbes whose memory I hold dear Tom
Lindsay and my Lab Mates
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Acknowledgments

• Funding
• Collections Study Grant
• ESIE Award 0119786
• Collections
• American Museum of Natural History, New York, NY
• Dr. Jin Meng Ms. Susan Koelle Bell
• Dr. John Wahlert Ms. S. Jean Spence
• Museum of Vertebrate Zoology, Berkeley, CA
• Dr. Chris Conroy Dr. Jim Patton
• Museum of Natural History, Gainesville, FL
• Dr. Richard Hulbert Dr. Laura Wilkins
• Museum of Vertebrate Biology, Portland, OR
• Dr. Luis A. Ruedas

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K-12 Battlefield

• Supernatural
• Intelligent Designer
• Irreducible Complexity
• vs
• Rational
• Descent with Modification
• Natural Selection

http//www.discovery.org/csc/
http//www.tortoisetours.com/files/Menu/gi_finches
.1.JPG
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Support for Evolution

• Believe????

http//www.the-funneled-web.com/NV_2005(Jan-Dec)/
NV_0504/news__views_item_april_2005-050428.htm
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Evolution in Oregon

• The Oregon science Content Standards, adopted in
  April 2001, clearly require the teaching of
  evolution.

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Oregon Standards on Inquiry

• Ask questions or develop hypothesis based on
  observations
• Design experiment
• Collect data
• Interpret results

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Methods

• 45 crania and mandibles
• 16 extinct xenarthrans skulls
• 23 extant xenarthran skulls
• 15 Dasypus novemcinctus skulls for a control
• 6 outgroup skulls
• 15 calipers 150 mm
• 5 calipers 600 mm
• Student notebooks
• Pre and Post assessment

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Assessment

• Identifying Testable Questions
• Biostratigraphy
• General Facts and Observations
• About xenarthrans
• Similarities within xenarthrans
• Differences within xenarthrans
• Observations about a xenarthran
• Observations about a dinosaur
• Phylogenetic Tree

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Pilosa Skulls

• Family Bradypodidae
• Bradypus tridactylus
• Family Megalonychidae
• Choloepus didactylus
• Choloepus hoffmanni
• Megalonyx leptostomus Florida Pleistocene
• 9 unknown small ground sloths specimens
  Argentina Miocene

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Pilosa Skulls

• Family Mylodontidae
• Catonyx tarijensis Bolivia Pleistocene
• Glossotherium chapadmalensis Florida Pliocene
• Scelidodon sp. Argentina Pleistocene
• Family Myrmecophagidae
• Myrmecophaga tridactyla
• Tamandua mexicana

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Cingulata Skulls

• Family Glyptodontidae
• Glyptodon calvipes Uruguay Pleistocene
• Panochthus tuberculatus Argentina Pleistocene
• Family Pampatheriidae
• Holmesina septentrionalis Florida Pleistocene
• Family Dasypodidae
• Dasypus novemcinctus
• Cabassous unicinctus
• Euphractus sexcinctus
• Priodontes maximus

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Participants

• Human Subjects Review approved
• 78 students participated average 10.8 hr.
• 35 signed permission
• 3 students missed post-assessment
• 32 participants total
• Normally distributed
• Paired Student-t test
• Student-t test with equal variance to assess
  student variables

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Student Demographics
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Student Demographics
Estimated 17 students on FRM
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Results - Significant

• Assessment Questions
• Testable Questions, p0.330 df31
  Mis-identified testable, p1.0000 df9
  Mis-identified nontestable, p0.0067 df9
  Mis-identified non vs test, p0.0002 df19
  

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Results - Significant

• Assessment Questions
• Facts, p7.3x10-5 df31 Factual statements,
  p0.004 df31 Xenarthran knowledge, p0.005
  df31 Same, p0.05 df31 Different, p0.005

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Results - Significant

• Assessment Questions
• Total, p0.003 df31
• Significant gain under the following parameters
• Over 11 hours exposure to materials p2.79x10-7
  df30
• Over 70 Free or Reduced Meals! p0.038 df30
• Average gain for lt50 1.65
• Average gain for gt70 5.79!

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Results Not Significant

• Assessment Questions
• Biostratigraphy, p0.325 df31
• Observations about a dinosaur, p0.379 df31
• Phylogenetic tree, p0.562 df31

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Conclusions

• Difficult for students to identify non-testable
  questions (gt? students thought that these were
  testable).
• Are armadillos empathetic?
• Are sloths slow because they are deep thinkers?
• Are sloths slow because they are lazy?
• Did anteaters lose all their teeth as a
  punishment because they wanted to eat little
  animals?

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Conclusions

• Students improved significantly in reciting facts
  about xenarthrans
• Number of hours of students participation was
  significant ( gt10.5)
• Schools with gt70 of student body in Free and
  Reduced Meal program gained significantly from
  the Pre to Post assessment

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Conclusions

• Students did not show significance in
  biostratigraphy or phylogenetic trees however,
  most classes asked questions related to
  biomechanics

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Student Graph
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Thank You