Symbiotic Relationship Between Clownfish And Sea Anemones
Vienna Ai Marie C. Valleser BS Bio
August 2, 2013
Animal Systematics (ZOOL102)
A Literature Review on
Symbiotic Relationship between Clownfish and Sea Anemones
Symbiosis is a close and often long-term interaction between two or more different biological species. It comes from the ancient Greek words syn meaning “together” or “with” and vios meaning “life” (ODZ). Symbiosis is fundamentally classified as ectosymbiosis and endosymbiosis. Ectosymbiosis or exosymbiosis is a type of symbiotic relationship where one organism lives on the exterior of the other. Examples of ectosymbionts are the ectoparasites such as lice and ticks living on the surface of their hosts. Endosymbiosis is the symbiotic relationship in which one symbiont lives within the tissues of the other, either …show more content…
within cells or extracellularly.
An example for this would be the bacteria Escherichia coli found in the colon of humans.
Symbiosis is also classified according to the tightness or looseness of the relationship. This classification can be obligate where one or both would die without the other, and facultative where the presence or absence of the other is not really necessary. Symbiosis can also be classified according to the extent to which organism benefits. This classification can be mutualism, commensalism, and parasitism. Mutualism is the type of relationship where both organisms benefit. Mutualistic relationships may be either obligate for both species, obligate for one but facultative for the other, or facultative for both. An example of mutualism is the relationship between plants and animals. Plants need carbon dioxide, which is a by-product in the respiration of animals, for photosynthesis while animals need oxygen, which is a by-product in the photosynthesis of plants, for cellular respiration. Commensalism is the type of relationship
where one organism benefits and the other is not significantly harmed nor helped. Commensal relationships may involve one organism using another for transportation, for housing, or it may also involve one organism using something another created after its death. An example of commensal relationship is that between barnacles and a whale. The barnacles benefit by finding a habitat where nutrients are available, without hampering or enhancing the survival of the
whale.
The last type of relationship is parasitism. It is parasitism when one symbiont benefits while the other is harmed. An example is the human and the tapeworm. The tapeworm derives food and shelter from the human host, while the human is denied of the nutrition that is consumed by the tapeworm.
Perhaps one of the most intriguing and perplexing relationships in the animal kingdom is that between clownfish and sea anemones. Their relationship has captivated people especially home aquarists since the 1970s. But never before has a fish had a bigger boost than the clownfish in the wake of Finding Nemo (Prosek, 2010). Most people did not know what a clownfish was until they saw the movie. Now it is one that even the young kids are able to easily recognize.
There are however more to clownfish than what was displayed in the movie. Clownfish are vertebrates of the Pomacentridae or damselfish family that live in tropical marine waters throughout the world. They are home loving creatures and live amongst the tentacles of sea anemones in the shallow waters of coral reefs. Sea anemones are members of the phylum
Cnidaria. They have stinging tentacles with specialized organelles called nematocysts
which secrete and discharge toxins that can paralyze both preys and predators (Pechenik, 2011).
Clownfish are the only fish known to be immune to the stings of the anemone. They do this by secreting a coating of slime and mucus similar to that found on the anemone itself, tricking the anemone into thinking that the fish is just another part of itself. The mucus creates an insulating
and protective layer that negates the effect of the stinging nematocysts (Drury, 2008). Clownfish use this relationship with anemone to help them stay away from predators. They are able to move about the tentacles while the predators are not. Another benefit clownfish get from anemones is that mutualistic relationship between the two triggers the adaptive radiation of clownfish (Litsios et al., 2012). Adaptive radiation is the process by which a single ancestral species diversifies into many descendants adapted to exploit a wide range of habitats. Mutualistic interactions allow species to access resources untapped by competitors, but evidence shows that the effect of mutualism on species diversification can greatly vary among mutualistic systems. The result of their study shows that clownfish morphological characters are linked with ecological niches associated with the sea anemones. The clownfish show an increase in the rate of species diversification as well as rate of morphological evolution compared to their closest relatives without anemone mutualistic associations.
Based on the described classifications of symbiosis, the clownfish-sea anemone relationship is ectosymbiosis since they do not live within tissues of the other; obligative for most species of clownfish since they are poor swimmers and leaving their home anemones will increase their mortality rate because of other species of fish that feed on them such as morays, trumpetfish, scorpionfish, large hawkfish, and snappers; and facultative for other species such as the orangefin (Amphiprion chrysopterus) and Clark 's anemonefishes (A. clarkii) for they are efficient swimmers and they usually come out and migrate from one anemone to another. In terms of which party or parties benefit, the classification is on the threshold of commensalism and mutualism. Some say that anemones can survive without the clownfish for they have another symbiont which is the zooxanthellae. Zooxanthellae are symbiotic dinoflagellates found in a variety of marine organisms, notably radiolarians, forminiferans, and ciliates among protozoans,
and many invertebrate hosts such as corals and sea anemones (Shoukr, 1997). Zooxanthellae are single-celled algae that have the ability to synthesize proteins from sunlight, so much more than it needs for its survival that it provides the excess to its host anemone, which is very significant to the survival and growth of the anemone (Drury, 2008). Recent studies however, show that sea anemone benefit from the clownfish as well, actually more than what is expected and more are being discovered. One of these is that because of the territorial attitude of the clownfish, they tend to drive away polyp-eating fish, thus protecting the anemone (Fautin, 1991). In some areas, anemones are quickly consumed if the clownfish are removed - the primary predators being the large butterflyfish. Another is that better water circulation is given to the sea anemone when the clownfish fans its fins while swimming. According to a very recent study, some clownfish waft oxygen-rich water over anemones at night to supplement their oxygen supply (Szczebak et al.,
2013). The study investigated metabolic and behavioral interactions between two-band anemonefish (Amphiprion bicinctus) and bulb-tentacle sea anemones (Entacmaea quadricolor) during nighttime. The researchers measured the net dark oxygen uptake of fish–anemone pairs when partners were separate from each other, together as a unit, and together as a unit but separated by a mesh screen that prevented physical contact. The results of their study show that physical contact between clownfish and sea anemones elevates the volume of oxygen uptake, and clownfish behavior at night appears to oxygenate sea anemone hosts and augment the metabolism of both partners. Another study shows benefits derived from excretion products of clownfish that are utilized by zooxanthellae which in turn provides energy for their host anemone
(Roopin et al., 2009). The researchers starved host anemones and were maintained with either clownfish or ammonia supplements or neither of the two. Results show that anemones with ammonia supplements express increase in abundance of zooxanthallae and provided the hosts
with more energy that minimized the host’s body size loss. Anemones with clownfish guests also yielded the same results. Anemones without ammonia supplements and clownfish guests however harbored significantly lower abundances of zooxanthellae and decreased greater than
60% of their body size. Hence, the study shows indirect benefit acquired by the sea anemones from their clownfish symbiont. Sea anemones also acquire phosphate nutrient from clownfish. A study was conducted to determine rates of phosphate excretion by clownfish and uptake by giant sea anemones under laboratory conditions, and compare them with known rates of ammonia transfer in the symbiosis (Godinot et al., 2009). The result showed that the rate of uptake of phosphate in anemone with clownfish symbiont is rapid compared to anemone cultured with only phosphate supplements. Under laboratory conditions, however, anemones absorb phosphate up to 6.6× faster than the rate at which it is excreted by their clownfish, and thus fish do not appear to provide sufficient phosphate to their hosts through this pathway. The researchers concluded that anemones may get most of their phosphorus via ingestion of fish feces and/or mucus, or via the ingestion of prey.
Contrary to what most people think, sea anemones actually benefit from their symbiont clownfish either directly or indirectly. Given that sea anemones are sessile, people only see the benefits the clownfish acquire from them which are protection from predators and as triggers for adaptive radiation. Studies however show the different benefits the sea anemone can get from the clownfish. Among the direct benefits are protection from anemone-eating fish, increase in net oxygen volume uptake, and uptake of phosphate nutrients. The indirect benefit include the excretion of clownfish of nitrogenous compound wastes which are taken up by other symbionts the zooxanthellae, increases their metabolism, and in turn supply more energy to the anemone.
The type of relationship the two organisms have therefore is mutualism and not commensalism.
References
[ODZ] Oxford Dictionary of Zoology. <http://www.oxfordreference.com/view/10.1093/ oi/authority.20110803100546707>. [accessed 2013 Jul 1]
Prosek, J. 2010 Jan. Beautiful friendship. National Geographic 217: 121-131.
Pechenik, J.A. 2011. Biology of the Invertebrates, 6th ed. McGraw-Hill, New York, NY,
p. 102.
Drury, F. 2008. Marine symbiosis: clownfish & anemones. PSA Journal 74(5): 28-31.
Litsios, G., Sims, C.A., Wüest, R.O., Pearman, P.B., Zimmermann, N.E., Salamin, N.
2012. Mutualism with sea anemones triggered the adaptive radiation of clownfishes. BMC Evolutionary Biology 12: 212.
Shoukr, F. A. 1997. Ultrastructure of the endosymbiont Symbiodinium microadriaticum from a sea anemone. Science (1): 25-34.
Fautin, D.G. 1991. The anemonefish symbiosis: what is known and what is not.
Symbiosis 10: 23-46.
Szczebak, J.T., 2013. Henry, R.P., Al-Horani, F.A., Chadwick, N.E. Anemonefish oxygenate their anemone hosts at night. J. Exp. Biol. 216: 970-976.
Roopin, N., Chadwick, N.E. 2009. Benefits to host sea anemones from ammonia contributions of resident anemonefish. J. Exp. Mar. Biol. Ecol. 370: 27–34.
Godinot, C., Chadwick, N.E. 2009. Phosphate excretion by anemonefish and uptake by giant sea anemones: demand outstrips supply. BMS 85(1): 1-9.
August 2, 2013
Animal Systematics (ZOOL102)
A Literature Review on
Symbiotic Relationship between Clownfish and Sea Anemones
Symbiosis is a close and often long-term interaction between two or more different biological species. It comes from the ancient Greek words syn meaning “together” or “with” and vios meaning “life” (ODZ). Symbiosis is fundamentally classified as ectosymbiosis and endosymbiosis. Ectosymbiosis or exosymbiosis is a type of symbiotic relationship where one organism lives on the exterior of the other. Examples of ectosymbionts are the ectoparasites such as lice and ticks living on the surface of their hosts. Endosymbiosis is the symbiotic relationship in which one symbiont lives within the tissues of the other, either …show more content…
within cells or extracellularly.
An example for this would be the bacteria Escherichia coli found in the colon of humans.
Symbiosis is also classified according to the tightness or looseness of the relationship. This classification can be obligate where one or both would die without the other, and facultative where the presence or absence of the other is not really necessary. Symbiosis can also be classified according to the extent to which organism benefits. This classification can be mutualism, commensalism, and parasitism. Mutualism is the type of relationship where both organisms benefit. Mutualistic relationships may be either obligate for both species, obligate for one but facultative for the other, or facultative for both. An example of mutualism is the relationship between plants and animals. Plants need carbon dioxide, which is a by-product in the respiration of animals, for photosynthesis while animals need oxygen, which is a by-product in the photosynthesis of plants, for cellular respiration. Commensalism is the type of relationship
where one organism benefits and the other is not significantly harmed nor helped. Commensal relationships may involve one organism using another for transportation, for housing, or it may also involve one organism using something another created after its death. An example of commensal relationship is that between barnacles and a whale. The barnacles benefit by finding a habitat where nutrients are available, without hampering or enhancing the survival of the
whale.
The last type of relationship is parasitism. It is parasitism when one symbiont benefits while the other is harmed. An example is the human and the tapeworm. The tapeworm derives food and shelter from the human host, while the human is denied of the nutrition that is consumed by the tapeworm.
Perhaps one of the most intriguing and perplexing relationships in the animal kingdom is that between clownfish and sea anemones. Their relationship has captivated people especially home aquarists since the 1970s. But never before has a fish had a bigger boost than the clownfish in the wake of Finding Nemo (Prosek, 2010). Most people did not know what a clownfish was until they saw the movie. Now it is one that even the young kids are able to easily recognize.
There are however more to clownfish than what was displayed in the movie. Clownfish are vertebrates of the Pomacentridae or damselfish family that live in tropical marine waters throughout the world. They are home loving creatures and live amongst the tentacles of sea anemones in the shallow waters of coral reefs. Sea anemones are members of the phylum
Cnidaria. They have stinging tentacles with specialized organelles called nematocysts
which secrete and discharge toxins that can paralyze both preys and predators (Pechenik, 2011).
Clownfish are the only fish known to be immune to the stings of the anemone. They do this by secreting a coating of slime and mucus similar to that found on the anemone itself, tricking the anemone into thinking that the fish is just another part of itself. The mucus creates an insulating
and protective layer that negates the effect of the stinging nematocysts (Drury, 2008). Clownfish use this relationship with anemone to help them stay away from predators. They are able to move about the tentacles while the predators are not. Another benefit clownfish get from anemones is that mutualistic relationship between the two triggers the adaptive radiation of clownfish (Litsios et al., 2012). Adaptive radiation is the process by which a single ancestral species diversifies into many descendants adapted to exploit a wide range of habitats. Mutualistic interactions allow species to access resources untapped by competitors, but evidence shows that the effect of mutualism on species diversification can greatly vary among mutualistic systems. The result of their study shows that clownfish morphological characters are linked with ecological niches associated with the sea anemones. The clownfish show an increase in the rate of species diversification as well as rate of morphological evolution compared to their closest relatives without anemone mutualistic associations.
Based on the described classifications of symbiosis, the clownfish-sea anemone relationship is ectosymbiosis since they do not live within tissues of the other; obligative for most species of clownfish since they are poor swimmers and leaving their home anemones will increase their mortality rate because of other species of fish that feed on them such as morays, trumpetfish, scorpionfish, large hawkfish, and snappers; and facultative for other species such as the orangefin (Amphiprion chrysopterus) and Clark 's anemonefishes (A. clarkii) for they are efficient swimmers and they usually come out and migrate from one anemone to another. In terms of which party or parties benefit, the classification is on the threshold of commensalism and mutualism. Some say that anemones can survive without the clownfish for they have another symbiont which is the zooxanthellae. Zooxanthellae are symbiotic dinoflagellates found in a variety of marine organisms, notably radiolarians, forminiferans, and ciliates among protozoans,
and many invertebrate hosts such as corals and sea anemones (Shoukr, 1997). Zooxanthellae are single-celled algae that have the ability to synthesize proteins from sunlight, so much more than it needs for its survival that it provides the excess to its host anemone, which is very significant to the survival and growth of the anemone (Drury, 2008). Recent studies however, show that sea anemone benefit from the clownfish as well, actually more than what is expected and more are being discovered. One of these is that because of the territorial attitude of the clownfish, they tend to drive away polyp-eating fish, thus protecting the anemone (Fautin, 1991). In some areas, anemones are quickly consumed if the clownfish are removed - the primary predators being the large butterflyfish. Another is that better water circulation is given to the sea anemone when the clownfish fans its fins while swimming. According to a very recent study, some clownfish waft oxygen-rich water over anemones at night to supplement their oxygen supply (Szczebak et al.,
2013). The study investigated metabolic and behavioral interactions between two-band anemonefish (Amphiprion bicinctus) and bulb-tentacle sea anemones (Entacmaea quadricolor) during nighttime. The researchers measured the net dark oxygen uptake of fish–anemone pairs when partners were separate from each other, together as a unit, and together as a unit but separated by a mesh screen that prevented physical contact. The results of their study show that physical contact between clownfish and sea anemones elevates the volume of oxygen uptake, and clownfish behavior at night appears to oxygenate sea anemone hosts and augment the metabolism of both partners. Another study shows benefits derived from excretion products of clownfish that are utilized by zooxanthellae which in turn provides energy for their host anemone
(Roopin et al., 2009). The researchers starved host anemones and were maintained with either clownfish or ammonia supplements or neither of the two. Results show that anemones with ammonia supplements express increase in abundance of zooxanthallae and provided the hosts
with more energy that minimized the host’s body size loss. Anemones with clownfish guests also yielded the same results. Anemones without ammonia supplements and clownfish guests however harbored significantly lower abundances of zooxanthellae and decreased greater than
60% of their body size. Hence, the study shows indirect benefit acquired by the sea anemones from their clownfish symbiont. Sea anemones also acquire phosphate nutrient from clownfish. A study was conducted to determine rates of phosphate excretion by clownfish and uptake by giant sea anemones under laboratory conditions, and compare them with known rates of ammonia transfer in the symbiosis (Godinot et al., 2009). The result showed that the rate of uptake of phosphate in anemone with clownfish symbiont is rapid compared to anemone cultured with only phosphate supplements. Under laboratory conditions, however, anemones absorb phosphate up to 6.6× faster than the rate at which it is excreted by their clownfish, and thus fish do not appear to provide sufficient phosphate to their hosts through this pathway. The researchers concluded that anemones may get most of their phosphorus via ingestion of fish feces and/or mucus, or via the ingestion of prey.
Contrary to what most people think, sea anemones actually benefit from their symbiont clownfish either directly or indirectly. Given that sea anemones are sessile, people only see the benefits the clownfish acquire from them which are protection from predators and as triggers for adaptive radiation. Studies however show the different benefits the sea anemone can get from the clownfish. Among the direct benefits are protection from anemone-eating fish, increase in net oxygen volume uptake, and uptake of phosphate nutrients. The indirect benefit include the excretion of clownfish of nitrogenous compound wastes which are taken up by other symbionts the zooxanthellae, increases their metabolism, and in turn supply more energy to the anemone.
The type of relationship the two organisms have therefore is mutualism and not commensalism.
References
[ODZ] Oxford Dictionary of Zoology. <http://www.oxfordreference.com/view/10.1093/ oi/authority.20110803100546707>. [accessed 2013 Jul 1]
Prosek, J. 2010 Jan. Beautiful friendship. National Geographic 217: 121-131.
Pechenik, J.A. 2011. Biology of the Invertebrates, 6th ed. McGraw-Hill, New York, NY,
p. 102.
Drury, F. 2008. Marine symbiosis: clownfish & anemones. PSA Journal 74(5): 28-31.
Litsios, G., Sims, C.A., Wüest, R.O., Pearman, P.B., Zimmermann, N.E., Salamin, N.
2012. Mutualism with sea anemones triggered the adaptive radiation of clownfishes. BMC Evolutionary Biology 12: 212.
Shoukr, F. A. 1997. Ultrastructure of the endosymbiont Symbiodinium microadriaticum from a sea anemone. Science (1): 25-34.
Fautin, D.G. 1991. The anemonefish symbiosis: what is known and what is not.
Symbiosis 10: 23-46.
Szczebak, J.T., 2013. Henry, R.P., Al-Horani, F.A., Chadwick, N.E. Anemonefish oxygenate their anemone hosts at night. J. Exp. Biol. 216: 970-976.
Roopin, N., Chadwick, N.E. 2009. Benefits to host sea anemones from ammonia contributions of resident anemonefish. J. Exp. Mar. Biol. Ecol. 370: 27–34.
Godinot, C., Chadwick, N.E. 2009. Phosphate excretion by anemonefish and uptake by giant sea anemones: demand outstrips supply. BMS 85(1): 1-9.