Add labels to the figure that follows, which illustrates the interacting factors in a declining population that contribute to the extinction vortex.

Question

Illustration of energy transfer from grass to deer and mountain lions, with biomass labels.

Accepted Answer

Welcome back. Let's look at our next problem, choose the correct labels for A. B and C. And the following ecological pyramid. And we have an ecological pyramid diagram here with four levels. The bottom level is labeled grass um with an amount of killin kilograms labeled on there. And then the next level up is lettered. The next level up is labeled letter A. Uh and says grasshoppers, letter B labels the next level up, which is frog. And then let her see python the top level. So we can assume these are trophic levels on our pyramid. And a trophic level is basically an organism's position in the food chain. To put it simply so its relationship to the primary source of energy. In this case the sun shone giving energy to the grass and its relationship to its food source and anything that praise on it. And then we also see um that we show arrows coming off to the right showing energy lost as heat from all four levels. So as organisms from the level above consume organisms from level below. They gain energy from them. But energy is lost as heat in that process. And there's a uh the concept of trophic efficiency is how much of that energy has passed between levels in that process. And that's about on average about 10%. So as you can see there's a lot of energy lost as heat in this process, only about 10% being transferred up. So now as we look at our pyramid and we see this label and kilograms down on the grass and we look at our answer choices and see the A. B. And C. Are all amounts in kilograms. And that the numbers seem to differ by a factor of 10. That makes sense. We're talking about 10% of energy being transferred from level to level. Um This amount of kilograms is probably biomass um either biomass uh at each level in terms of organisms or it could be a net productivity pyramid. The amount of biomass that's um net production of biomass at each level. But we need um that larger level of biomass at the lower levels to sustain the upper levels. Since we have that low level of trophic efficiency. So with that 10% number in mind, we would expect starting here with grass at 18,600 kg of biomass. We'd expect when we go to the level above level a. That we'd only see 10% of the biomass. So we'd expect to see 1860 kg for level a. So when we look at our answer choices, we see that choice C. And choice D. Have that amount for level A. So we can go ahead and eliminate choices A. And B. And then we'd expect level B. Two B. 10% of that, which is gonna be 186 kg and only answer choice C. Has that amount. So we can go ahead and eliminate answer choice D. And then we just confirm that an answer choice c. Level C is 10% of level B 18. kg. So we would say that answer choice C represents the correct labeling of levels A B and C on this ecological pyramid. See you in the next video.

Add labels to the figure that follows, which illustrates the interacting factors in a declining population that contribute to the extinction vortex.

Verified video answer for a similar problem:

Key Concepts

Trophic Levels

Energy Transfer Efficiency

Extinction Vortex