Carrion Definition and Explanation
Carrion is dead animal matter, which may also be actively decaying. Any animal which dies leaves a carcass, or the remains of their body. This material is eaten by scavengers, and is further reduced to small pieces of organic material known as detritus. Carrion serves as a major source of food for many carnivores and omnivores.
Both vertebrates and invertebrates utilize carrion as a source of food, particularly protein. All carnivores and omnivores eat carrion, but to different extents. Using comparative anatomy, scientists can study the teeth and digestive tract of an organism to understand if it eats a lot of carrion. Felines and animals like ferrets are obligate carnivores, and prefer live prey. Their teeth and digestive tract reflect this. Their canines are long, sharp, and much larger than their other teeth. This is for incapacitating live prey with a bite to the neck or throat. They also have very sharp teeth used for slicing and swallowing whole chunks of meat. Meat is easy to digest, and as such these organisms have shortened digestive tracts.
On the other hand, omnivores like dogs and bears that feed on a lot of carrion have distinct changes to their dentition. These animals have molars in the back of their jaw, which help to grind and separate tough tissues like bone and cartilage. They also have sharp teeth and large canines, but not to the extent that the felines do. If you look at the colon of a carrion eater, you will see it is usually relatively longer than that of an obligate carnivore, as these animals must be able to process every scrap of food they can find. A similar case can be found in birds. Birds which eat carrion have sharp beaks and talons to tear bite-size chucks from a carcass. Many fish and aquatic animals specialize on carrion, such as the lamprey, hagfish, and piranha.
Besides the carnivorous vertebrates, there are a number of invertebrates that specialize on carrion. Crabs, for example, provide an essential service of breaking down carrion and spreading the nutrients around. Many worms, insects and other small invertebrates also help with the breakdown of a large carcass. The reproductive lifecycle of many of these insects includes a larval stage (such as a maggot) which feeds on carrion. At a certain point, when the pieces of carrion are so small that only the smallest organisms like ants, worms, and bacteria can feed on them, they are known as detritus. Detritus is further broken down by these tiny organisms (detritivores) into organic nutrients, which can then be absorbed by plants and used to build new tissue. Thus the cycle of life continues.
References
- Brusca, R. C., & Brusca, G. J. (2003). Invertebrates. Sunderland, MA: Sinauer Associates, Inc.
- Feldhamer, G. A., Drickamer, L. C., Vessey, S. H., Merritt, J. F., & Krajewski, C. (2007). Mammology: Adaptation, Diversity, Ecology (3rd ed.). Baltimore: The Johns Hopkins University Press.