• Animal cells and systems
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• v.9 no.1
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• pp.13-18
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• 2005

Cannibalism plays important roles at the levels of both individual and population. To enhance overall rate of successful survival and reproduction, salamander larvae may have evolved to consume both conspecifics and heterospecifics. Consuming conspecifics could result in decreased inclusive fitness possibly by killing relatives. In several salamander species, discrimination of salamander larval siblings from non-siblings and heterospecifics to avoid such a risk has been reported. To determine whether the Korean salamander larvae consume non-siblings more often than siblings and to analyze prey preferences of the salamander larvae in several different experimental conditions, a series of foraging experiments was conducted in the laboratory. We found that 1) large cannibal larvae preyed on small sibling more often than small non-sibling in a mixed group of sibling and non-sibling, 2) cannibal larvae prefered to consume live, weak, and small larvae to dead, healthy, and large larvae, and 3) cannibal larvae consumed heterospecific tadpoles more often than conspecific nonsibling larvae in a mixed group. In addition, the larval density was positively correlated with the occurrence of spacing behavior, one of the agonistic predator behaviors among salamander larvae.

• Development and Reproduction
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• v.15 no.2
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• pp.77-85
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• 2011

To investigate the influence of density and feeding frequency (food amount) on growth, cannibal dynamics and survival of puffer Takifugu obscurus (TL $25.0{\pm}0.5$ mm, BW $0.53{\pm}0.03$ g) during early life history, we conducted one experiment composed with 6 density groups set up as 1.43 inds./${\ell}$, 2.14 inds./${\ell}$, 2.86 inds./${\ell}$, 3.57 inds./${\ell}$, 4.29 inds./${\ell}$ and 7.14 inds./${\ell}$. The experiment was triplicately performed in 1 ton FRP tank for 30 days. Daily food intake (DFI), feed efficiency (FE), growth, cannibal frequency, and survival rates were examined. Although not find any significant relation of density to DFI and FE, we found that growth decreased significantly with the increasing of density under 3.57 inds./${\ell}$, but significantly increased with the increasing of density over 4.29 inds./${\ell}$. Cannibal frequency and daily mortality rate was significantly increased with increasing density and decreasing feeding frequency, inducing the most poor survival rate in the highest density group and low feeding frequency. Therefore, we concluded that the density and the feeding frequencies affect sibling cannibal dynamics and survival of puffer stock.

• The Journal of the Korea Contents Association
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• v.11 no.3
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• pp.190-200
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• 2011

Different from visible horror elements that confront the characters directly and do physical harms, invisible horror elements are expressed through suggestion and imagination and their realities are not disclosed. For the disclosure of the realities of invisible horror elements, they are expressed through the overturned relation between the subject and victim of horror as in 'The Others' or through body snatching as in 'The Happening' and 'Paranormal Activity'. The overturn of relation and body snatching are connected to cannibalism in that the former causes a sudden change of personality and the latter takes the body of others. Cannibalism and the change of personality belong to the formalization and illogic of lower order resulting from cannibalism. The meaning of invisible horror elements in films seems to be contradictory to the original meaning of cannibalism, which is entering the sphere of utopian freedom, but considering that the reversed role resolves conflicts and tensions from terror and gives relief from fear, the meaning may be consistent with the spirit of cannibalism, namely, entering 'the sphere of freedom. In this study, the author attempted to analyze how the expression and plot of films showing invisible horror elements are related with cannibalism.

• Korean Journal of Environment and Ecology
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• v.26 no.3
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• pp.342-347
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• 2012

This study was conducted to demonstrate the relationship between experience of cannibalism and difference of phenotype in the Korean salamander Hynobius leechii from March to April 2011. We examined whether the different polyphenism of larval salamander is induced as a result of indirect cannibalism in early life cycle. We divided into two groups(one group continuously exposed to the indirect cannibalism and the other group never exposed to the cannibalism). We measured the head width at the level of eyes(HWE), the largest head width(LHW) and snout-vent length(SVL) of the each larva then calculated the ratio of the head size by dividing HWE by LHW. We found that exposure of indirect cannibalism in early life cycle cause the different polyphenism. Our result means the larval salamander responded to the chemical cue from conspecific.

• Journal of Wetlands Research
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• v.15 no.4
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• pp.485-491
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• 2013

This study examined the cannibalistic polyphenism of larval salamander Hynobius leechii by the level of predation risk. Salamander eggs were collected from three regions (Mountain Inwang, Mountain Surak and Gwangju). Eggs were treated by three different risk conditions: (1) high risk, predation risk three times a day; (2) medium risk, predation risk once a day; and (3) low risk, no predation risk. Predation risk was conducted using a chemical cue from Chinese minnows. The chemical cue treatment started from the day of collection and ended one week after hatching. Post-treatment measurements were head width at the level of the eyes (HWE), largest head width (LHW), and Snout-vent length of the each larva. To compare the morphological change according to the predation risk, we modified the two head size, HWE and LHW, to HWE/LHW. A significant difference in HWE/LHW and snout-vent length was evident according to the level of predation risk. And larval mortality was increase by the predation risk. The results indicate that predation risk can cause cannibalistic polyphenism of larval salamander and this morphological change could influence larval mortality.

• Korean Journal of Environment and Ecology
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• v.24 no.6
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• pp.744-750
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• 2010

This study examined the different polyphenism of larval salamander Hynobius ieechii according to two habitats, pond and stream. We collected salamander's eggs from three regions including Mountain Inwang, Surak and Gwangju. Eggs were treated by four different conditions according to predation level and habitat: high risk - which had a predation risk three times a day; low risk - which had no predation risk, pond and stream habitat. Predation risk was conducted by using chemical cue from Chinese minnows. The chemical cue treatment started from the day of collection and ended one week after the hatching. After the treatment phase, we measured the head width at the level of the eyes(HWE) and the largest head width(LHW) and snout-vent length of the each larva. We calculated the ratio of the head size by dividing HWE by LHW and made a comparison with each of the average ratio of head size according to the predation risk. The results showed that there was a significant difference in the ratio of the head size and snout-vent length according to the predation risk and habitat. From these results we found that predation risk and habitat condition can cause the different polyphenism to the larval salamander and these morphological changes could be affect their mortality.