Resistance of Resistance of Anemonefish to the Sea Anemonefish to the Sea

Anemone: Innate or Anemone: Innate or Acquired through Acquired through

Acclimation Behavior?Acclimation Behavior?Based on the following paper by Elliot and Based on the following paper by Elliot and

Mariscal: “Acclimation or Innate Protection of Mariscal: “Acclimation or Innate Protection of Anemonefishes to Sea Anemones?”Anemonefishes to Sea Anemones?”

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Background: Symbiotic Background: Symbiotic RelationshipRelationship

Sea anemone & Sea anemone & anemonefish anemonefish relationshiprelationship

Big Question: How Big Question: How can anemonefish can anemonefish swim freely among swim freely among the stinging the stinging tentacles of the sea tentacles of the sea anemone?anemone?

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Background: Controversy, Innate Background: Controversy, Innate or Acquired Resistance?or Acquired Resistance?

InnateInnate

versusversus

Acclimation Acclimation behaviorbehavior

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OR, could it be a combination???

Methods: Elliott & Mariscal’s Methods: Elliott & Mariscal’s ExptsExpts

Expt 1:Expt 1: Are there variations in Are there variations in protection amongst species and protection amongst species and developmental stages of anemonefish?developmental stages of anemonefish?

How did they test? Forced-contact testsHow did they test? Forced-contact tests*72 different species combinations*72 different species combinations*Fish eggs, larvae and juveniles*Fish eggs, larvae and juveniles

Methods: Expts continuedMethods: Expts continued

Expt 2Expt 2: Innate protection from : Innate protection from anemones?anemones?

How did they test? Forced-contact testsHow did they test? Forced-contact tests

*Tested 3 species of anemones with 3 *Tested 3 species of anemones with 3 species of NAÏVE anemonefishspecies of NAÏVE anemonefish

A. clarkii

Methods: Expts continuedMethods: Expts continued

Expt 3: Does mucus coat of associated Expt 3: Does mucus coat of associated and naïve anemonefish resemble and naïve anemonefish resemble mucus of anemone?mucus of anemone?

How did they test? Immunological How did they test? Immunological techniquestechniques

*ELISA test- compared antigens of *ELISA test- compared antigens of anemone mucus with mucus coat of anemone mucus with mucus coat of naïve and associated naïve and associated A.clarkii A.clarkii

Results: Experiment 1 Results: Experiment 1

Results: Expt 1 continuedResults: Expt 1 continued

Clownfish- generalist; protected from Clownfish- generalist; protected from wide variety of anemoneswide variety of anemones

P. Biaculeatus- P. Biaculeatus- specialist; resistant only to specialist; resistant only to its host anemoneits host anemone

A. Percula (clownfish)

P. Biaculeatus

Results: Experiment 2Results: Experiment 2

Natural host: normally found together in the wild

Unnatural: do not normally associate in the wild

Results: Expt 2 continuedResults: Expt 2 continued

Fish Fish speciesspecies

AnemoAnemone ne species species testedtested

# # fish fish testetestedd

# fish # fish protectprotecteded

# fish # fish adheriadheringng

# fish # fish escapiescapingng

A.clarkA.clarkiiii

H.CrispaH.Crispa

S.HaddoniS.Haddoni

M.DoreensM.Doreensisis

33

33

55

33

33

44

00

00

11

00

00

11

A.ocellA.ocellarisaris

H.CrispaH.Crispa

S.HaddoniS.Haddoni

M.DoreensM.Doreensisis

55

55

55

00

55

00

55

00

55

55

00

55

A.peridA.perideraioneraion

S.HaddoniS.Haddoni

M.doreensiM.doreensiss

22

2222

0000

2200

22

TotalTotal 3030 1717 1313 1313

Results: Experiment 3Results: Experiment 3

Associated fish have more anemone antigens on their mucus coat relative to naïve fish

ConclusionsConclusions

Expt 1: Variation in protection; generalist Expt 1: Variation in protection; generalist versus specialist species of fishversus specialist species of fish

Expt 2: Naïve individuals of anemonefish Expt 2: Naïve individuals of anemonefish were innately protected from natural hostwere innately protected from natural host

Expt 3: Associated fish chemically Expt 3: Associated fish chemically camouflage themselves during acclimation camouflage themselves during acclimation behavior behavior

DiscussionDiscussion

Naïve Naïve A. clarkiiA. clarkii do not produce mucus do not produce mucus coat similar to anemone, but after coat similar to anemone, but after associating/acclimation they have associating/acclimation they have similar antigenssimilar antigens

Innate protection demonstrated in Expt Innate protection demonstrated in Expt 2:2: Observations: fish performed acclimation Observations: fish performed acclimation

behavior, even when not initially stung behavior, even when not initially stung (innately protected)(innately protected)

Acclimation may provide further protectionAcclimation may provide further protection

Critiques & Further StudiesCritiques & Further Studies

FURTHER STUDIESFURTHER STUDIES

1.1. Interspecific variation Interspecific variation in protection of in protection of anemonefish-evolutionanemonefish-evolution

2.2. Isolate specific Isolate specific biochemical biochemical compounds in mucus compounds in mucus that cause protectionthat cause protection

3.3. Mutagenesis—innately Mutagenesis—innately protected fishprotected fish

CRITIQUES

1. Eggs were in close proximity to anemones before forced-contact tests

2. Use larger sample size for Expt 2

ReferencesReferences

1. Elliott J.K., Mariscal R.N., and K.H. Roux. 1994. Do 1. Elliott J.K., Mariscal R.N., and K.H. Roux. 1994. Do anemonefishes use molecular mimicry to avoid being stung anemonefishes use molecular mimicry to avoid being stung by host anemones? J. Exp. Mar. Biol. Ecol. 179: 99-113.by host anemones? J. Exp. Mar. Biol. Ecol. 179: 99-113.

2. Elliott J.K., and R.N. Mariscal. 1997. Acclimation or 2. Elliott J.K., and R.N. Mariscal. 1997. Acclimation or Innate Protection of Anemonefishes. Copeia. 2: 284-289.Innate Protection of Anemonefishes. Copeia. 2: 284-289.

3. Elliott J.K., and R.N. Mariscal. 1997. Ontogenetic and 3. Elliott J.K., and R.N. Mariscal. 1997. Ontogenetic and interspecific variation in the protection of anemonefishes interspecific variation in the protection of anemonefishes from sea anemones. J. Exp. Mar. Biol. Ecol. 208: 57-72from sea anemones. J. Exp. Mar. Biol. Ecol. 208: 57-72

4. Mebs, D. 1994. Anemonefish symbiosis: vulnerability 4. Mebs, D. 1994. Anemonefish symbiosis: vulnerability and resistance of fish to the toxin of the sea anemone. and resistance of fish to the toxin of the sea anemone. Toxicon. 32: 1059-1068.Toxicon. 32: 1059-1068.

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