Why Are Big Fierce Animals Rare
According to Colinvaux, big animals are rare because the energy that is available in every step of their food chain is degraded (Colinvaux, 1990). The heat that the body system converts into energy is lost during the animal’s food chain. Colinvaux argues that big animals decrease due to natural selection (Colinvaux, 1990). He proceeds to state that through natural selection, big animals get minimal favor in terms of finding resources and survival methods. According to researchers Kern and Grigg, in the big animal’s food chain, there is insufficient transfer of energy from one individual to the other (Kern & Griggs, 2005).
For example, Grigg states that the energy used in creating the food of a bird is only 10 percent (Kern & Griggs, 2005). In this case, the food of the bird, which is hawk, is a worm. Looking across the levels of the food web, each group of predator enlarges and become fiercer comparing with the last one. In addition to this, it is advisable to note that the amount of energy in the food web continues to decline (Colinvaux, 1990). In this case, the available space for a big fierce predator on top the web is minimal. This makes it impossible for the big animal to consume all the others in the food web. In such a system the amount of energy that scientists estimate hawk bring into the process of photosynthesis is 1/1000 (Morrison, 2001).
The less the energy available in this system means that small number of individuals can get support. This means that the big animals will be few in number in their ecosystem. In his research, Kern and Grigg adds that when the big fierce animal cannot harm those predators that might harm him (Kern & Griggs, 2005). Because of this reason, predators make sure they escape possible dangers when getting food. Case study of fish in Great Lake explains how it is easy to understand that big fierce animals are rare because of the energy degradation in their food chain. The following is food chain illustrating an ocean biome.
Trophic level
Ocean Bimeo
Primary produce phytoplankton (for example, diatoms)
Primary consumer zooplankton (for example, crab larvae)
Secondary consumer fish (scallops)
Tertiary consumer seal
Quarterly consumer white shark
In the above food chain, the primary producer is the source food for all organisms in the ecosystem. The arrows indicate how energy flow from deep vents in the lake to the top predator, which is the white shark. As the food chain illustrates, a lot of energy is lost in the chain each time an organism eats the other. According to Colinvaux, the big animal may experience shortage of food when one of the species in the chain goes extinct because this will affect the entire chain (Colinvaux, 1990). The following data shows how the big fierce animals become extinct due to lose of energy in their chain using the example of fishes.
Ocean Biomeo 2005 2006 2007
Diatoms 30 metric tones 20 metric tones 10metric tones
Crab larvae 50000species 40000species 30000species
Scallops 20000species 15000species 10000species
Seal 10000species 5000species 3000species
White Shark 5000species 3000species 1000species
According to the data above, the primary producer, which are the Diatoms are many in number and this creates good environment for survival for the primary consumer. As the chain goes on, more energy is lost and the top consumer receives little food to feed on. When the food decreases in the chain due to natural calamities, the quarterly consumer suffers most and this leads to big fierce animals becoming rare (Berger & Shor, 2009).
Reference
Berger, W. H., & Shor, E. N. (2009). Ocean: reflections on a century of exploration. New York: University of California Press.
Colinvaux, P. A. (1990). Why big fierce animals are rare. New York: Penguin Books.
Kern, J. D., & Griggs, I . (2005). This America. New York: Kessinger Publishing.
Morrison, M. L. (2001). Wildlife study design. New York: Springer.
Zeder, M. A. (2006). Documenting domestication: new genetic and archaeological paradigms. New York: University of California Press.
