Question

8th grade science sensemaking smart starts
name: ____ core: ____
ls.8.2.2
construct an explanation to summarize the relationships among producers, consumers, and decomposers including the positive and negative consequences of such interactions including: coexistence and cooperation, competition (predator/prey), parasitism, and mutualism.
prompt # 1
smart start
scientists studied a forest ecosystem and recorded population changes in three species over five years, as shown in the table below. what patterns do you notice in the relationship between the deer, wolves, and oak trees? how does the decline of one group affect the others?

year	deer population	wolf population	oak tree growth
2	600	18	medium
3	750	15	low
4	900	10	very low
5	1100	5	none

student response

Explanation:

Step1: Analyze Wolf and Deer Populations

Wolf population (20→18→15→10→5) decreases. Deer population (500→600→750→900→1100) increases.

Step2: Analyze Deer and Oak Trees

Deer population rises, oak tree growth (High→Medium→Low→Very Low→None) declines.

Step3: Explain Interactions

Wolves (predators) decline, so deer (prey) increase. More deer eat more oak trees (producers), reducing oak growth. A decline in wolves (predator) leads to deer overpopulation, harming oak trees. A decline in oak trees would later limit deer (if food is scarce), and then wolves (if deer decline).

Answer:

• Pattern: Wolf population decreases, deer population increases, oak tree growth decreases.
• Impact: Wolf decline → deer overpopulation → more oak tree consumption → reduced oak growth. Later, oak decline could limit deer, then wolves.