Investigative MacroevolutionInvestigators: Dianne Burpee, Shu-Mei

Chang, Mark Farmer, Paula Lemons, Kim Nelson, and Denise Woodward

UGAUGA

Facilitators: Kelley Harris-Johnson and Lillian Tong

Learning Goal Measurable Outcome

Understand the nature of science Formulate a hypothesis and ways to test it

Understand that all life has a common ancestry

List/define common characteristics of life

Associate apomorphies (shared derived character) with well-defined groups of organisms

•Define apomorphy•When given a phylogenetic tree, identify the apomorphies that define groups of organisms•Describe apomorphies for a major group of organisms•Use apomorphies to infer evolutionary relatedness

Investigative Macroevolution: Teachable Unit

Target Audience: Introductory Biology (Majors and Non-Majors)

Learning Goal Measurable Outcome

Understand that classifications are a human-made construct and are subject to change based on new data

•Describe the history of classification from Aristotle to Woese•Find a current article (within the last year) that has lead to the reclassification of an organism

Understand the continuum between micro- and macro- evolution

Describe the mechanisms by which apomorphies arise

Understand how investigative macroevolution relates to something meaningful

•Build a phylogenetic tree from data•Interpret a phylogeny•Describe how a phylogeny can be used to address additional questions in science

Investigative Macroevolution: Teachable Unit

Unit Timeline• Topics and activities

– History and change of biological classification schemes

– Discussion of common characteristics of life and shared-derived characteristics of major groups of organisms

– Analysis of character data– How to construct phylogenetic trees from character

data– How to interpret phylogenetic trees

Investigative Macroevolution: Teachable Tidbit

• Learning Goal and Objectives– Understand how Investigative Macroevolution

relates to something meaningful• Build a phylogenetic tree from a data matrix• Interpret a phylogeny• Apply phylogenetic analysis to solve a clinical

mystery

Recap From Last Class Chloroplast Cuticle Stomata Vascular Pollen Flowers

Green algae X

Mosses X X X

Ferns X X X X

Gymnosperms X X X X X

Angiosperms X X X X X X

Data Matrix

Resulting Phylogeny

Activity • DO NOT start until you have been told to GO

1.Construct a data matrix using the data strips that you will find in the large envelope.

2.Open envelope 1 and circle the best tree that fits the data matrix and provide group name.

3.One team member run to front with your tree.

1 2 3 4 5 6 7 8 9 10 11 12C. elegans

1 2 3 7

Clicker Q1. Which of the following phylogenetic trees matches the tree you constructed from your data matrix?A. B.

C. D.

Chytrid

Myxozo

a

Trypanoso

me

Giardia

C. elegans

Ascaris

Chlamydia

Staphylo

-

coccu

sAmanita

Candida

Strepto-

coccu

s

The Correct Phylogeny - B

Bacteria Protists Fungi Animals

What’s Ailing Roberto?

You are a clinical microbiologist who specializes in identifying parasitic infections.

• A physician has brought you a sample of a pathogenic organism from a critically ill 22 year old male patient who has not responded to standard treatment.

• He has no known underlying health conditions but has presented with:– severe intestinal symptoms including severe

diarrhea and wasting– A lung X-ray reveals inflammation and fluid in the

lungs.

• His physician took a sample of fluid from his lungs and isolated the microorganism seen below:

Who am I ??

Remove the new data strip from the envelope 2 and determine where this mystery organism fits within your data matrix

Chytrid

Myxozo

a

Trypanoso

me

Giardia

C. elegansAsca

ris

Chlamydia

Staphylo

-

coccu

s Amanita

Candida

Strepto-

coccu

s

Bacteria Protists Fungi Animals

Clicker Q2. Which organism in the matrix is most closely related to the mystery pathogen?

A. MyxozoaB. C. elegansC. CandidaD. TrypanosomaE. Staphylococcus

HELP !!!!!

• The clinical microbiologists now know this organism is most like Candida. Let’s determine a treatment for Roberto.

Clicker Q3. Use the table below to select the drug you would try first to treat Roberto.

A. TamifluB. SulfisoxazoleC. CefazolinD. Natamycin

Drug Mechanism of action

Tamiflu Inhibits the enzyme neuraminidase. Neuraminidase enables some viruses to release themselves from host cells.

Sulfisoxazole Inhibit folic acid synthesis (bacteria and most eukaryotes must make, mammals acquire in diet)

Cefazolin Inhibits peptidoglycan formation in cell walls.Natamycin Makes holes in fungal cell membranes but not human cell

membranes.

What additional information do you need?

Drug Mechanism of action

Tamiflu Inhibits the enzyme neuraminidase. Neuraminidase enables some viruses to release themselves from host cells.

Sulfisoxazole Inhibit folic acid synthesis (bacteria and most eukaryotes must make, mammals acquire in diet)

Cefazolin Inhibits peptidoglycan formation in cell walls.

Natamycin Makes holes in fungal cell membranes but not human cell membranes.

Which drug should be used first?

1. Natamycin•It makes holes in fungal cell membranes.•The mystery organism is closely related to other fungi.

2. Sulfisoxazole•It interferes with folic acid synthesis.•Most fungi make folic acid, but not all eukaryotes do.•It is currently unknown if the mystery pathogen makes folic acid.

Why not cefazolin?

Why not tamiflu?

Microsporidia a Microsporidia a group of parasitic group of parasitic fungifungi