why are there rarely more than four links in a food chain?

Answer 1

It's a matter of the biomass that must exist in each level. If there are five links in a food chain,

-- for every 1 kg that the organism on that upper level weighs, there must be 10 kg in the fourth level
-- and 100 kg in the third level
-- and 1000 kg in the second level
-- and 10,000 kg in the first level

If we ate on the fifth level, lets see what that would mean. Consider a smallish 110 pound (50 kg) high school girl. For her to survive eating only on the fifth level, there would have to be 50 times 10,000 kg, or 500,000 kg, of plant matter in the environment that just goes toward supporting her food needs. If you think in pounds and not kg, 110 times 10,000 = 1,100,000 pounds = 550 tons of plant matter to support her food needs. That's not going to work.

That's why there are the most producers, not as many primary consumers, and even fewer secondary consumers.

Answer 2

Because if u have more than four chains it normally could be seen as a food web.

Answer 3

It is possible, but I am not 100% certain

Answer 4

thanks to each and everyone of you for the replies.