1.Energy flows through (lost as heat); matter cycles
2.Pyramids can be disrupted by invasives, disease, or climate
3.Invasive Species Disruption: Invasive species disrupt energy flow by competing with native organisms for resources, altering established food webs, and thriving without natural predators. This cascading effect can reshape entire ecosystem energy pathways.
[!] STUDY GUIDE: Big Ideas
Use to answer form questions!
1.Ecosystems are dynamic balancing acts. Remove or
add one species, and the whole system tips.
2.Invasive species exploit systems without defenses.
Native species evolved together; invasives skip co-evolution.
Predator Removed->Prey Explodes->Plants Overgrazed->Habitat Lost->More Species Decline
TOP-DOWN TROPHIC CASCADE (Use the 10% rule from W1!)
[#] KEY TERMS
Define in YOUR words
Invasive species
A non-native species that harms the ecosystem
Trophic cascade
Effects ripple through food web
Keystone species
A species with outsized impact on its ecosystem
Biocontrol
Using predators to control pests
[?] THE PHENOMENON
Write BEFORE Hook form
How can introducing 102 toads destroy an entire continent's
ecosystems?
In 1935, Australia brought 102 cane toads from Hawaii to control
beetles. Today: 200+ MILLION toads. They didn't eat beetles—they ate
everything else. Their toxic skin kills any predator that tries to
eat them.
Your initial thinking:
[>] AFTER HOOK FORM
Reflect, then continue+2 pts
I learned that...
Station 1 — Trophic Cascades
When predators are removed...
The effect ripples because...
Key insight:
Station 2 — Case Studies
The invasive species disrupted...
Native species were harmed by...
Key insight:
[/] DAY 1 EXIT TICKET
Complete before leaving+5 pts
Q1:
If ALL wolves were removed from Yellowstone, what would happen to
willows? Trace the cascade.
Q2:
Using the 10% rule (W1), why are there so few apex predators in any
ecosystem?
Confidence:
Ecosystem Disruption & Invasive Species (continued)
Name:
[=]Day 2 start
Station 3 — Interventions & Solutions
One intervention strategy is...
This works (or fails) because...
A tradeoff or unintended consequence...
Key insight:
[+] MAKING CONNECTIONS
Use for Exit Ticket!
Apply the 10% rule (W1): Why does removing top predators cause
dramatic cascades?
Why do island species suffer MORE from invasives? Think about C3
natural selection.
[/] DAY 2 EXIT TICKET
Final check before Science Circle+5 pts
Q1 (NEW):
How do invasive species disrupt energy flow in food webs? Give a
specific example.
Q2 (SPIRAL):
Apply the 10% rule (W1): Why does removing top predators cause
dramatic cascades?
Q3 (INTEGRATION):
How do trophic cascades connect to energy pyramids? What pattern
appears in ALL disrupted ecosystems?
CHECKTEST YOUR THINKINGRate each: FALSE ← 1–2–3–4–5 → TRUE
1. Invasive species only affect the organisms they directly eat or compete with.
F12345T
2. Removing one species from a food web only breaks a single energy pathway.
F12345T
3. In competition between species, the physically strongest organism always wins.
F12345T
4. Predator and prey populations naturally stay in perfect balance without fluctuations.
F12345T
5. Invasive species often succeed because they lack natural predators in their new environment.
F12345T
Pick any TWO statements — especially any you rated 2, 3, or 4. Justify your rating with evidence:
Statement #___ — I rated it ___ because:
Statement #___ — I rated it ___ because:
[O] SCIENCE CIRCLE
~15 min | End of week+3 pts
[!] My "Aha!" Moment
[?] My Remaining Question
Discussion Protocol: Share ahas, listen actively,
record class discoveries.