Pyramids in parasitic food chains show inverted numbers due to many small consumers

Steps:

• Identify trophic levels: tree (producer), leaf fleas (primary consumers), emerging insects (secondary consumers), birds (tertiary consumers), feather fleas (quaternary consumers).
• For biomass pyramid: standing crop decreases upright from base to top, as larger organisms hold more mass (e.g., tree biomass > birds).
• For numbers pyramid: often inverted in parasite chains, with few producers but many parasites per host (e.g., one tree supports thousands of fleas).
• Match to diagrams: upright pyramid (1) fits biomass; inverted with high top numbers (4) fits numbers.

Why C is correct:

• Option C assigns upright pyramid 1 to biomass (decreasing mass per level) and inverted 4 to numbers (many parasites exceed hosts), per ecological definitions.

Why the others are wrong:

• A: Misassigns numbers to 3, likely upright, ignoring parasite abundance.
• B: Wrongly pairs biomass with 2 (possibly inverted) and numbers with 4.
• D: Incorrectly links biomass to 2, violating upright biomass rule.

Final answer: C