Structuring a Scientific Presentation
What is the Purpose?
Relay information to peers (usually)
Summarize your research (or someone else’s)
Good news – the paper already organizes this for you!
Introduction/Background
Methods
Results
Assignment help – Discussion/Conclusion
Acknowledgements
Each section 1 to several slides each, depending on length of talk
Don’t forget a title slide!
Title of the talk
Your name
Your affiliation(s)
Invasion Potential and Ecological Impacts
of Exotic Earthworms
in a Temperate Deciduous-Forest Ecosystem
Transition from title to Darwin
“prob don’t spend a lot of time thinking about ew’s, but very imp ecological, a fact recog by darwin, who called them on e of the most imp orgs ever”
4
Introduction/Background
Start wide, narrow down into your topic
Bring your audience up to speed
Gives your topic relevance – how does it fit in to the bigger picture?
Objectives of the study
My Thesis Background Information
Ecological significance of earthworms
Earthworms as an invasive species
Impacts in Michigan forests
My specific objectives
Study impacts of newly documented invasive earthworm species
Compare those impacts to previously established invasive earthworm species
Look for interactive effects between new & previous invaders
Methods
Describe the study design
Describe rationale for study design
How was each variable measured? What tests were used?
How were data analyzed?
Visuals help a lot here
Experimental Design: Field
Amynthas hilgendorfi
Control
Lumbricus rubellus
Both species
X5
Study Site: OU Biological Preserve
1.2 m
Word enclosure, don’t get out, spent night…, fully crossed randomized block design
Mention densities (140/plot = approx 93/sq meter = realistic)
Change pic to block design w/ all 4 together
-talk about how awesome keith was about putting these in, have pic pop up and disappear
Stress replication
Interactive effects – L vs. A
8
Experimental Design: Laboratory
40 mesocosms
500 g earthworm-free soil
10 earthworms
Basswood leaves
Same treatments
A. hilgendorfi
L. rubellus
Both species
No earthworms added
6 week incubation
Assignment help – Discuss why did in lab too, specifically (soil type, humidity, etc)
Words – complementary, controlled, more reps so greater ability to detect effects, closed system
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Parameters Measured
Leaf-mass loss
Soil ash-free dry mass (organic carbon content)
Soil NO3-, NH4+, SRP
Total earthworm biomass
Above-ground vegetation biomass
Microbial decomposition assay
Endomycorrhizal spore counts
Soil aggregate size
Soil pH
Soil respiration
A. hilgendorfi growth rates
Spend less time here
Mention statistical analysis: ANOVAs followed by Tukey comparisons (blocked for the field), discuss methods for each briefly
Give donna props for nutrients stuff
Ok to lose ppl on stats stuff for a bit
10
Results
Emphasize most important findings
Should include figures/visuals
Make sure orient your audience to the figures
Results: Leaf-mass loss
Field
Lab
SE
Why it’s important, remind of treatments
Set up in terms of relevance for each slide (incl. methods) – why is this measurement imp., describe methods and why we care, show you understand why you are measuring something
12
Results: Soil Aggregate Size
Assignment help – Discussion/Conclusions
Not just repeating results
Interpret them, put them into context
Link results to study objectives
Limitations
Recommendations
Conclusions
L. rubellus consumes more leaf litter while A. hilgendorfi appears to consume soil and leaf litter
A. hilgendorfi increased available N and P over control and L. rubellus treatments
Interactive effects were not observed
A. hilgendorfi impacts are significant, but different from those of L. rubellus
Clean this up
15
Acknowledgements & Questions
Thank you’s are standard practice for seminar/conference talks
Funding sources, collaborators, lab members, supervisor
Offer to take any questions the audience may have
Acknowledgements
Dr. Scott Tiegs
Andrew Stonehouse
Cassandra Belcher
My Committee Members
Dr. Keith Berven
Dr. George Gamboa
Dr. Donna Kashian
Dr. Dave Costello
Tim, Jeff, and Stream Ecology Lab
Ashley Burtner
Crystal Moon and Josh Martin
Mac Callaham Jr.
Dr. Liu and Dr. Hitt
Dr. Dvir
Rhita, Jan, Sheryl, and Cathy
Adam
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Slide Design Tips
Less is more (high “info to ink ratio”)
Clarity more important than being fancy
Create sections with clear titles
Keep it readable
Use plenty of visuals
Informative titles
“Leaf Mass Loss Varied Among Treatments ” more helpful than just “Results”
Don’t just read from the slides!
Public – more energy toward relevance & major takeaways (then provide evidence)
Usually less interested in methods & analysis
Your Article Analysis Presentation
Someone else’s research
YOU are evaluating it
Still need to be clear about intro/methods/results/conclusions
But you are providing an analysis too
As outlined in assignment rubric
More creative & structural freedom- outside sources, visuals, clips, background information, etc.
