The biomass pyramid above shows how a large amount of plant matter is eaten by many small animals which are in turn eaten by fewer numbers of large animals. At each step of the biomass pyramid, matter and energy are lost in the form of energy to keep the animal warm and moving, or as faeces and urine. Therefore, the more steps there are in a biomass pyramid, the more loss of matter and energy that occurs.
Humans are usually at the top of the Food Chain or biomass pyramid (unless we are eaten by sharks, lions or bears!). Also, there is often a significant loss of matter and energy at each step that can be avoided.
Does that mean that we should all become vegetarians? No. However, we can eat more vegetables and less meat.
Food security is an important issue too. Starving people fight for food for themselves and their children.
Feeding huge numbers of people requires large farms to grow staple foods such as wheat and rice. This has its problems:
- Natural animal and plant habitats are destroyed to make way for monoculture farms.
- Irrigation water is redirected from natural watercourses, again destroying indigenous fauna and flora.
- Pests are often indiscriminately sprayed with pesticides that are harmful to other animals.
