An ecologist studying a Scottish Highland pine forest models the organization of the ecosystem using the nested framework shown in the diagram below:
Let the levels be defined as follows:
- L1L_1L1: The entire physical environment (soil, water, climate) and all living organisms of the forest.
- L2L_2L2: All the interacting populations of different species in the forest (pines, deer, red squirrels, birds, hedgehogs).
- L3L_3L3: A group of red squirrels (Sciurus vulgaris) living and interbreeding within a specific area of the pine forest.
- L4L_4L4: A single red squirrel (Sciurus vulgaris).
Which of the following represents the correct sequence of these ecological levels, ordered from the least inclusive (smallest) to the most inclusive (largest) level?
L4→L3→L2→L1L_4 \rightarrow L_3 \rightarrow L_2 \rightarrow L_1L4→L3→L2→L1
L4→L2→L3→L1L_4 \rightarrow L_2 \rightarrow L_3 \rightarrow L_1L4→L2→L3→L1
L1→L2→L3→L4L_1 \rightarrow L_2 \rightarrow L_3 \rightarrow L_4L1→L2→L3→L4
L4→L3→L1→L2L_4 \rightarrow L_3 \rightarrow L_1 \rightarrow L_2L4→L3→L1→L2