掠食者的威脅是很多生物的天擇壓力，為了偵測掠食者的出現，可利用視覺、嗅覺、觸覺或水的波動等直接或間接方式來感測。在台灣南部墾丁萬里桐的潮間帶有為數頗多的蜈蚣櫛蛇尾 (Ophiocoma scolopendrina)，由於牠們在野外受傷機會大，可能會用上述機制來因應掠食者。而他們的掠食者可能很多種，所以本研究想要知道這種蛇尾對於掠食者是否有感知能力。我們提出假說解釋可能的躲避行為：(一) 這是針對掠食者的一種適應，藉由察覺同種受傷個體散發的味道，躲避掠食者；(二) 這是針對不適環境的一種逃避，藉由躲避陌生的味道，逃離一般不適環境，而同樣也達到逃離掠食者的效果。實驗發現蜈蚣櫛蛇尾對於同種的內臟液，約有一半以上的受測個體會有躲避的行為，而對於其他的測試液，例如魚、豬、藻類及淡水，則沒有類似行為。此行為雖無法百分之百躲掉掠食者，但至少可降低遇到掠食者的機會，由此可支持假說(一)並否定假說(二)，而不同的潮汐時間並不影響其反應。濃度的測試則發現10-1-10-3g/ml的內臟液均有過半的個體會躲避，而隨著濃度下降躲避個體也跟著遞減。在生殖季卵液誘導成功率為43%情況下，測試了卵和內臟的混合液發現，其對混合液的反應偏向針對只有內臟液時的躲避行為。此外也比較了同屬另一種陽燧足齒櫛蛇尾(Ophiocoma dentata)，此種陽燧足也會對本種和蜈蚣櫛蛇尾的內臟液有躲避行為。結果顯示，此兩種櫛蛇尾的內臟液可能代表掠食者出現時的警告訊息，且蜈蚣櫛蛇尾的躲避行為是為了適應掠食者的出現，而非躲避陌生的環境。

Predators may play an important role in affecting the fitness of preys. Many organisms have thus evolved strategies to prevent predation. Recognition of predator presence may be achieved by vision, olfaction, tactile sense or detection of water motion. Some organisms sense predators directly; others associate the injuries of victims to the presence of predators. There are many brittlestars (Ophiocoma scolopendrina) at the intertidal zone of Kenting, southern Taiwan and they suffer high frequencies of injuries in the wilds. Since their predators are likely to be diverse, we want to know if O. scolopendrina has the ability to sense the presence of predators, indirectly. We have two hypotheses: firstly, the avoidance behavior is elicited specifically in response to predators, secondly, the avoidance behavior is a general response to unfamiliar elements in the water mass. Our experiments revealed that the tested individuals would avoid conspecific viscera liquids and also that of other echinoderms’. They are more likely to respond to conspecific viscera liquids. And O. scolopendrina hardly respond to solutions prepared from other organisms, e.g., fish, pork, macroalgae, freshwater. This behavior may help brittlestars reduce the probability of encountering predators. The results are compatible with the first hypothesis only. The effect of tide was also explored by testing in different times, but the frequencies of avoidance responses were independent of the tide. Furthermore, the subtidal species Ophiocoma dentata was also tested for the behavior. They escaped from conspecific viscera liquid as well as that of O. scolopendrina. This species, however, could not distinguish the liquids from the two brittlestar species. In conclusion, the avoidance behaviors of the ophiocomid brittlestars are adaptations for avoiding predators, not for avoiding unfamiliar environments.

壹、前言 1
貳、材料方法 5
參、結果 9
肆、討論 12
參考文獻 17

沈驗，1992，小琉球蜈蚣櫛蛇尾陽隧足(Ophiocoma scolopendrina)的生殖和再生。國立中山大學海洋生物研究所碩士論文。台灣。

林晏如，2006，兩種櫛蛇尾在生殖時於空間及時間上的適應。國立中山大學海洋生物研究所碩士論文。台灣。

張鼎，1999，齒櫛蛇尾及蜈蚣櫛蛇尾生殖誘導之研究。國立中山大學海洋生物研究所碩士論文。台灣。

Aizenberg, J., A. Tkachenko, S. Weiner, L. Addadi and G. Hendler, (2001). "Calcitic microlenses as part of the photoreceptor system in brittlestars." Nature 412(6849): 819-822.

Alexander, J. E. Jr. and A. P. Covich, (1991). "Predation risk and avoidance behavior in two freshwater snails." Biological Bulletin 180: 387-393.

Bollache, L., N. Kaldonski, J. P. Troussard, C. Lagrue, T. Rigaud, (2006). "Spines and behaviour as defences against fish predators in an invasive freshwater amphipod." Animal Behaviour 72: 627-633.

Bryan, P. J., J. B. McClintock and T. S. Hopkins, (1997). "Structural and chemical defences of echinoderms from the northern Gulf of Mexico." Journal of Experimental Marine Biology and Ecology 210: 173 –186.

Campbell, A. C., S. Coppard, C. D'Abreo and R. Tudor-Thomas, (2001). "Escape and aggregation responses of three echinoderms to conspecific stimuli." Biological Bulletin 201(2): 175-185.

Casas, J., S. Bacher, J. Tautz, R. Meyhöfer and D. Pierre, (1998). "Leaf Vibrations and Air Movements in a Leafminer-Parasitoid System. " Biological Control,. 11(2): 147-153.

Elewa, A. M. T., (2007). Predation in Organisms - A Distinct Phenomenon. Springer-Verlag Berlin Heidelber

Ferrari, M. C. O., F. Messier and D. P.Chivers, (2006). "The nose knows: minnows determine predator proximity and density through detection of predator odours." Animal Behaviour 72: 927-932.

Grober, M. S., (1988). "Brittle-star bioluminescence functions as an aposematic signal to deter crustacean predators. " Animal Behaviour 36(2): 493-501.

Hagen, N. T., A.Andersen, and O. B. Stabell, (2002) "Alarm responses of the green sea urchin, Strongilocentrotus droebachiensis, induced by chemical labeled durophagous predators and simulated acts of predation. " Marine Biology 140: 365 –374.

Hemmi, J. M., (2005). "Predator avoidance in fiddler crabs: 2. The visual cues." Animal Behaviour 69: 615-625.

Karlson, P. and M. Luscher, (1959). "Pheromones - New Term for a Class of Biologically Active Substances." Nature 183(4653): 55-56.

Kats, L.B. and L.M. Dill, (1998). "The scent of death: Chemosensory assessment of predation risk by prey animals." Ecoscience 5(3): 361-394.

Kerfoot, W. C. and A. Shi, (1987). "Predation: direct and indirect impacts on aquatic communities. " University Press of New England. 203-224.

Kiesecker, J.M. and D.K. Skelly, (2000). "Choice of Oviposition Site by Gray Treefrogs: The Role of Potential Parasitic Infection. " Ecology 81(10): 2939-2943.

Lin, Y. J., K. Soong, (2009). Spawning behaviors of two congeneric brittle stars. Marine Ecology Progress Series: 387:157-165

Mac Arthur, R. H., E. O. Wilson (1967). "The theory of island biogeography." Princeton University Press, Princeton, New Jersey.

Majer, A. P., J. R.Trigo and L. F. L. Duarte, (2009). "Evidence of an alarm signal in Ophiuroidea (Echinodermata)." Cambridge Journals Online. Vol: 2.

McClintock, J. B., R. A. Angus, C. Ho, C. D.Amsler and B. J.Baker, (2008). "A laboratory study of behavioral interactions of the Antarctic keystone sea star Odontaster validus with three sympatric predatory sea stars." Marine Biology 154(6): 1077-1084.

Mirza, R. S. and D. P. Chivers, (2003). "Influence of body size in the response of fathead minnows, Pimephales promelas, to damselfly alarm cues. " Ethology 109: 691 –699.

Nicolai, V.M. and K.P. Judith, (2006). "Detection and avoidance of an entomopathogenic fungus by a generalist insect predator." Ecological Entomology 31(2): 162-171.

Nordlund, D.A. and W.J. Lewis, (1976). "Terminology of chemical releasing stimuli in intraspecific and interspecific interactions." Journal of Chemical Ecology 2(2): p. 211-220.

Phillips, D. W., (1976). "The effect of a species-specific avoidance response to predatory starfish on the intertidal distribution of two gastropods." Oecologia 23(2): 83-94.

Raphael, R. W. and J. P. Valerie, (2007). "Marine benthic invertebrates use multimodal cues for defense against reef fish." Marine Ecology-Progress Series. 340: 29-39.

Sloan, N.A. and S.M. Northway, (1982). "Chemoreception by the asteroid Crossaster papposus (L.)." Journal of Experimental Marine Biology and Ecology. 61(1): 85-98.

Snyder, N. and H. Snyder, (1970). "Alarm Response of Diadema Antillarum." Science 168(3928): 276.

Soong, K., Y. Shen, S.-H. Tseng, C.-P. Chen, (1997). Regeneration and potential functional differentiation of arms in brittlestar, Ophiocoma scolopendrina (Lamarck) (Echinodermata: Ophiuroidea). Zoological Studies. 36(2):90-97.

Soong, K., D. Chang and S. M. Chao, (2005). "Presence of spawninducing pheromones in two brittle stars (Echinodermata: Ophiuroidea)." Marine Ecology-Progress Series. 292:195–201.

Soong, K., Y. J. Lin, S. M. Chao and D. Chang, (2009). "Spawning time of two shallow-water brittle stars." Marine Ecology-Progress Series 376: 165-171.

Vadas, R. L. and R. W. Elner, (2003) "Responses to predation cues and food in two species of sympatric, tropical sea urchins. "Marine Ecology 24:102 –121.