In the absence of water fleas, the rotifer population levels off as it reaches a high density, likely due to factors such as limited resources (such as phytoplankton), increased competition among rotifers, and potential environmental carrying capacity, which can restrict growth. Additionally, at high population densities, increased predation pressure from rotifers on their own food sources may also lead to a decline in phytoplankton availability, further stabilizing their population.
Rotifers and water fleas are predatory omnivores, eating phytoplankton, bacteria, and other microorganisms. Two flasks are prepared. Both flasks contain rotifers and phytoplankton, but Flask Z also contains water fleas.
This graph shows the populations.
The graph shows number of rotifers on the y-axis from 0 to 4500, in increments of 500. The x-axis is labeled as days. The data is as follows. Day 0: number of rotifers alone and number of rotifers with water fleas, 0. Day 2: number of rotifers alone and number of rotifers with water fleas, 0. Day 4: number of rotifers alone and number of rotifers with water fleas, 300. Day 6: number of rotifers alone and number of rotifers with water fleas, 500. Day 8: number of rotifers alone and number of rotifers with water fleas, 800. Day 10: number of rotifers alone, 1700 and number of rotifers with water fleas, 1600. Day 12: number of rotifers alone, 3000 and number of rotifers with water fleas, 1500. Day 14: number of rotifers alone, 4000 and number of rotifers with water fleas, 1100. Day 16: number of rotifers alone, 4200 and number of rotifers with water fleas, 200. Day 18: number of rotifers alone, 4200 and number of rotifers with water fleas, 0.
Analyze the graph and identify some factors that may contribute to the rotifer population leveling off in the absence of water fleas. Explain your answer in 1–2 sentences.
1 answer