When we think of cannibalism, our minds immediately turn to gruesome pictures of humans eating other humans or fictional characters that feast upon the flesh of other living people (especially with a nice chianti and fava beans). Though cannibalism may not be a common occurrence among humans, it is a fairly widespread practice upon many other species of the animal kingdom. This paper will explore the behavior of cannibalism in the tiger salamander (Ambystoma tigrinum) a major fitness cost of cannibalism in these organisms: pathogen transmission.
Cannibalism is operationally defined as the ingestion of all or part of a conspecific, and is taxonomically widespread amongst many vertebrate and invertebrate groups; however, it is extremely infrequent in most species (Dawkins, 1976; Elgar and Crespi, 1992). It is believed that there are numerous fitness benefits to cannibalism, including better balance of nutrients from conspecifics over heterospecifics, and a competitive advantage of killing close competitors. There are also some fitness costs, which are believed to be associated with the rarity of cannibalism, including, increased risk of injury to the cannibal, diminishment of the indirect component of their inclusive fitness by killing relatives, and the heightened probability of acquiring deleterious pathogens and parasites above that experienced by non-cannibalistic predators (Dawkins, 1976; Elgar and Crespi, 1992; Hamilton, 1964; Pfennig, 1991, 1997; Sherman, 1981).
As previously mentioned, cannibalism is uncommon in many species. However, in the tiger salamander (A. tigrinum), it is a very common occurrence. Tiger salamanders have two life-history stages including a larval form and an adult form. During the larval stag...
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... is common in many salamanders and possibly the cause of these infections, the authors never actually test the water for Clostridium specifically (Pfennig et al., 1991, 1997). Thus, the pathogens within the study could be viral or bacterial, and could potentially have different transmission rates and affects on the salamanders. Another point of contention within the methodology of the study is that they did not actually test whether the deceased animals died from infection or were actually infected. Rather, they simply compared growth rate, isolation observations, and death rates of healthy to “diseased” animals (Pfennig et al., 1991, 1997). Pfennig et al. (1991) did note, from their parasite density comparisons, that though cannibals did carry more parasites than typicals simply because the cannibals were larger (no correlation of parasite number to body size).
In their article, “The Six-Legged Meat of the Future,” Dicke and Van Huis argue that due to the decline in the supply of meat in America, we should begin to use insects as an “alternate animal protein”
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...his builds a relationship between the two causing the predator to consume its meat without looking away (Pollan 307). This causes that person to no want to know what they are eating because people are used to not knowing what they are eating.
Goldman, Laurence R. "Cannibalism." Macmillan Encyclopedia of Death and Dying. 2003 ed. N.p.: Gale Group, 2002.Encyclopedia.com. Web. 20 Mar. 2014. .
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Shark slaughter has led to shark populations being rapidly decimated all around the globe. Fishermen report that sharks are also getting smaller because they are not being given enough time to fully mature. Although there are other fish that are targeted more than sharks, they are not exactly affected by the kind of endangerment that sharks are currently experiencin...
Typical Western thought directs people to examine the practices of cannibalism as savage and primitive. More often than not, this type of association exists because the people viewing the action are frightened and confused by that which they do not understand. In fact, some would even claim that, “cannibalism is merely a product of European imagination” (Barker, 2), thereby completely denying its existence. The belief that cannibalism goes against “human instinct”, as seen in many literary works including Tarzan, reduces those who practice it to being inhuman. (Barker, 1) However, scientific findings demonstrate that those who practice cannibalism are still human despite their difference in beliefs; therefore, not only can rationalization be extrapolated from those who practice the act of cannibalism, but also denying the fact of the participant’s very humanity has been undermined through scientific findings.
...e Animals and Satisfy Meat Eaters?” Journal of Agricultural and Environmental Ethics 21.6 (2008): 580-96. Web. 3 Apr. 2014.
Due to the use of Anthropophagy for leisure purposes, it is evident that cannibalism is a topic of much interest among humans, aside from its label as a social taboo. Technically, a human’s eating of another human has a chemical effect on the blood. Too much human meat causes a build up of vitamin A and amino acids such as homocysteine in the bloodstream, which could cause congenital defects in future offspring. However, if human organs which are rich in B vitamins and folic acid are eaten along with the human meat, homocysteine is not able to metabolize in the bloodstream. This means that cannibalism could hypothetically be the basis of a healthy diet (“Natural Food”).
of parasites do not kill the host from feeding, whereas a predator will kill it’
...e. "A Hypothesis to Explain the Role of Meat-Eating in Human Evolution." Www.cnr.berkely.edu. 4 Feb. 2001. Web. .
Ethical eating and food selection reveal that responsibility: “modern meat and animal products and industries are also explored.” (Crocombe 88) The author believes that the simple facts are enough to make consumers make the mental link between the awful lives of the animals that live and die for the purpose of