More individuals at lower levels

The idea

The lower trophic levels of an ecosystem generally have a greater number of individuals, the greatest number being producers.

Counting a grassland

A grassland has grass plants, insects, frogs and snakes.

Which of these would you expect to be present in the greatest number?

• The grass plants
• The frogs
• The snakes

Count the levels

Press Next step.

Wide at the bottom

Going up the trophic levels, the number of individuals generally gets smaller. The lower levels have a greater number of individuals, and the greatest number is of the producers.

The lower trophic levels of an ecosystem generally have a greater number of individuals, the greatest number being the producers.

Notes

Lower trophic levels generally have more individuals; the producers have the most.

Check yourself

In an ecosystem, which trophic level generally has the greatest number of individuals?

Going up from the producers to the larger carnivores, the number of individuals generally ...

In the picture, which row has the most dots?

• The herbivores. Herbivores are at the second level. The greatest number is of the producers.
• The producers — correct. Yes!
• The larger carnivores. Larger carnivores are at the top, the fourth level, and have fewer individuals than the levels below.
• becomes larger. The lower trophic levels generally have the greater number of individuals.
• stays the same. The number is generally greatest at the lowest level and gets smaller higher up.
• becomes smaller — correct. Yes!
• The producers, the lowest level — correct. Yes!
• The larger carnivores, the highest level. The larger carnivores row has the fewest dots. The lower levels generally have more individuals.
• None, the rows have equal numbers of dots. The rows do not have equal numbers. The lower the level, the more dots it has.