Answer: by being smart and pog and swag
Explanation:
As you go up in an ecosystem the bigger animals have less energy. While the organisms down at the bottom like plants that create their own energy have greater amounts. This is because energy is rated doing everyday things. As energy travels up the food pyramid, it looses more and more energy. This is knower as the 10% rule. In which every time you go up 10% of energy is lost.
Digestion takes place inside Iysosomes containing digestive enzymes. Hope I helped!
The fossil record shows a sequence from simple bacteria to more complicated organisms through time, it is very reliable because it is physical evidence and by studying fossils, scientists can learn how much (or how little) organisms have changed as life developed on Earth.
I think its a density dependent limited factor