Ecology
Associations
Known predators
Echinoidea (Urchins) is prey of:
Enhydra lutris
Actinopterygii
Homo sapiens
Sicyases sanguineus
Heliaster helianthus
Chondrichthyes
Carangidae
phytoplankton
organic stuff
Cheloniidae
Decapoda
Stomatopoda
Anomura
Asteroidea
Echinoidea
Urophycis chuss
Gadidae
Melanogrammus aeglefinus
Leucoraja erinacea
Leucoraja ocellata
Amblyraja radiata
Macrozoarces americanus
Anarhichas
Tautogolabrus adspersus
Pleuronectes ferrugineus
Scophthalmus aquosus
Pleuronectes americanus
Hippoglossoides platessoides
Lophius americanus
Based on studies in:
USA: Alaska, Aleutian Islands (Coastal)
Pacific: Bay of Panama (Littoral, Rocky shore)
Puerto Rico, Puerto Rico-Virgin Islands shelf (Reef)
USA, Northeastern US contintental shelf (Coastal)
Chile, central Chile (Littoral, Rocky shore)
This list may not be complete but is based on published studies.
Enhydra lutris
Actinopterygii
Homo sapiens
Sicyases sanguineus
Heliaster helianthus
Chondrichthyes
Carangidae
phytoplankton
organic stuff
Cheloniidae
Decapoda
Stomatopoda
Anomura
Asteroidea
Echinoidea
Urophycis chuss
Gadidae
Melanogrammus aeglefinus
Leucoraja erinacea
Leucoraja ocellata
Amblyraja radiata
Macrozoarces americanus
Anarhichas
Tautogolabrus adspersus
Pleuronectes ferrugineus
Scophthalmus aquosus
Pleuronectes americanus
Hippoglossoides platessoides
Lophius americanus
Based on studies in:
USA: Alaska, Aleutian Islands (Coastal)
Pacific: Bay of Panama (Littoral, Rocky shore)
Puerto Rico, Puerto Rico-Virgin Islands shelf (Reef)
USA, Northeastern US contintental shelf (Coastal)
Chile, central Chile (Littoral, Rocky shore)
This list may not be complete but is based on published studies.
- C. A. Simenstad, J. A. Estes, K. W. Kenyon, Aleuts, sea otters, and alternate stable-state communities, Science 200:403-411, from p. 404 (1978).
- B. A. Menge, J. Lubchenco, S. D. Gaines and L. R. Ashkenas, A test of the Menge-Sutherland model of community organization in a tropical rocky intertidal food web, Oecologia (Berlin) 71:75-89, from p. 85 (1986).
- J. C. Castilla, Perspectivas de investigacion en estructura y dinamica de communidades intermareales rocosas de Chile Central. II. Depredadores de alto nivel trofico, Medio Ambiente 5(1-2):190-215, from p. 203 (1981).
- Link J (2002) Does food web theory work for marine ecosystems? Mar Ecol Prog Ser 230:19
- Opitz S (1996) Trophic interactions in Caribbean coral reefs. ICLARM Tech Rep 43, Manila, Philippines
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Known prey organisms
Echinoidea (Urchins) preys on:
detritus
macroalgae
phytoplankton
algae
colonial sessile invertebrates
Asteroidea
Echinoidea
Priapula
Polychaeta
Ophiuroidea
Hemichordata
Holothuroidea
Echiuroidea
Sipunculidae
Bivalvia
Porifera
Cnidaria
Anthozoa
Ostreoida
Gastropoda
Based on studies in:
USA: Alaska, Aleutian Islands (Coastal)
Pacific: Bay of Panama (Littoral, Rocky shore)
Chile, central Chile (Littoral, Rocky shore)
USA, Northeastern US contintental shelf (Coastal)
Puerto Rico, Puerto Rico-Virgin Islands shelf (Reef)
This list may not be complete but is based on published studies.
detritus
macroalgae
phytoplankton
algae
colonial sessile invertebrates
Asteroidea
Echinoidea
Priapula
Polychaeta
Ophiuroidea
Hemichordata
Holothuroidea
Echiuroidea
Sipunculidae
Bivalvia
Porifera
Cnidaria
Anthozoa
Ostreoida
Gastropoda
Based on studies in:
USA: Alaska, Aleutian Islands (Coastal)
Pacific: Bay of Panama (Littoral, Rocky shore)
Chile, central Chile (Littoral, Rocky shore)
USA, Northeastern US contintental shelf (Coastal)
Puerto Rico, Puerto Rico-Virgin Islands shelf (Reef)
This list may not be complete but is based on published studies.
- C. A. Simenstad, J. A. Estes, K. W. Kenyon, Aleuts, sea otters, and alternate stable-state communities, Science 200:403-411, from p. 404 (1978).
- B. A. Menge, J. Lubchenco, S. D. Gaines and L. R. Ashkenas, A test of the Menge-Sutherland model of community organization in a tropical rocky intertidal food web, Oecologia (Berlin) 71:75-89, from p. 85 (1986).
- J. C. Castilla, Perspectivas de investigacion en estructura y dinamica de communidades intermareales rocosas de Chile Central. II. Depredadores de alto nivel trofico, Medio Ambiente 5(1-2):190-215, from p. 203 (1981).
- Link J (2002) Does food web theory work for marine ecosystems? Mar Ecol Prog Ser 230:19
- Opitz S (1996) Trophic interactions in Caribbean coral reefs. ICLARM Tech Rep 43, Manila, Philippines
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Evolution and Systematics
Functional Adaptations
Functional adaptation
Thin "shells" resist impact loading: sea urchins
"Some of the few relatively large shells with thin walls are those of sea urchins and other echinoid echinoderms. They resemble pressure-supported structures…but they lack the requisite internal pressures (Ellers and Telford 1992), so they have to have proper shells, at least in the engineering sense. For the biologist, they have 'tests' rather than 'shells,' and the latter distinction isn't just our usual terminological proliferation. Tests, unlike shells, are growing structures of articulated hard elements. For some, at least, collagen-swathed sutures permit significant local deformation, which should reduce impact loading and thus offset some of the hazards of a thin shell (Telford 1985). Nonetheless, they do smash easily…The best rationalization I can offer for why sea urchins tolerate such fragility is that the wave forces don't provide either piercing loads or a sudden hammering impact." (Vogel 2003:388)
Learn more about this functional adaptation.
The hard outer coverings of some sea urchins, called 'tests', allow local deformation that may resist impact loading by incorporating collagen-swathed sutures.
"Some of the few relatively large shells with thin walls are those of sea urchins and other echinoid echinoderms. They resemble pressure-supported structures…but they lack the requisite internal pressures (Ellers and Telford 1992), so they have to have proper shells, at least in the engineering sense. For the biologist, they have 'tests' rather than 'shells,' and the latter distinction isn't just our usual terminological proliferation. Tests, unlike shells, are growing structures of articulated hard elements. For some, at least, collagen-swathed sutures permit significant local deformation, which should reduce impact loading and thus offset some of the hazards of a thin shell (Telford 1985). Nonetheless, they do smash easily…The best rationalization I can offer for why sea urchins tolerate such fragility is that the wave forces don't provide either piercing loads or a sudden hammering impact." (Vogel 2003:388)
Learn more about this functional adaptation.
- Steven Vogel. 2003. Comparative Biomechanics: Life's Physical World. Princeton: Princeton University Press. 580 p.
- Ellers, O; Telford, M. 1992. Causes and consequences of fluctuating coelomic pressure in sea urchins. The Biological Bulletin. 182(3): 424-434.
- Telford, M. 1985. Domes, arches and urchins: the skeletal architecture of echinoids (Echinodermata). Zoomorphology. 105: 125-134.
- Ellers, O; Johnson, AS; Mober, PE. 1998. Structural strengthening of urchin skeletons by collagenous sutural ligaments. The Biological Bulletin. 195(2): 136-144.
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Functional adaptation
Shape distributes stress: sea urchin
"Spheres are also distorted by gravity. If a drop of liquid, held together by surface tension, is placed on a surface and therefore subjected to the force of gravity, it tends to become a more flattened shape, called 'oblate'. The shell of a sea urchin, stripped of its spines, is oblate. This shape distributes stress evenly over the surface and therefore reduces the likelihood of cracking or breaking. The guiding principle of economy is always apparent: a shape is most efficient when it reduces its work to a minimum." (Foy and Oxford Scientific Films 1982:20)
Learn more about this functional adaptation.
The shell of sea urchins prevent cracking and breaking via oblate shape.
"Spheres are also distorted by gravity. If a drop of liquid, held together by surface tension, is placed on a surface and therefore subjected to the force of gravity, it tends to become a more flattened shape, called 'oblate'. The shell of a sea urchin, stripped of its spines, is oblate. This shape distributes stress evenly over the surface and therefore reduces the likelihood of cracking or breaking. The guiding principle of economy is always apparent: a shape is most efficient when it reduces its work to a minimum." (Foy and Oxford Scientific Films 1982:20)
Learn more about this functional adaptation.
- Foy, Sally; Oxford Scientific Films. 1982. The Grand Design: Form and Colour in Animals. Lingfield, Surrey, U.K.: BLA Publishing Limited for J.M.Dent & Sons Ltd, Aldine House, London. 238 p.
Trusted
Functional adaptation
Radiating shape makes for efficient transport: sea urchin
"If you let a drop of ink fall on a piece of paper, the splash pattern that results looks rather like a sea urchin. If you drop water into a bowl of liquid and photograph the moment of impact with high-speed equipment, the coronet shape formed at the surface resembles a sea anemone. Yet another of the basic shapes of life - the explosion, or radiating shape - repeats the forms taken by falling drops of water. Radiating shapes occur wherever numerous lines fan outwards from a single central point - whether in a flat plane, as with a starfish, or in three dimensions, as with a sea urchin. The plant kingdom is full of radiating shapes: the majority of flowers have this form, and many plants grow leaves that radiate directly from a stem base; but there are many examples in the animal kingdom as well. Radiating lines, as a construction design, have two useful attributes: they minimize the distance between the centre and the outlying points, and they provide great scope for increasing the surface area of an organism…The first of these qualities is most convenient in cases where materials must be transported rapidly from the centre to outer points or vice versa. There is a disadvantage, however. If there are a lot of outlying points, the lines tend to become overcrowded around the centre (diagram a). One way to overcome this problem is to develop branching patterns, to reduce the total length of travel and the congestion of lines at the centre (diagram b). If each artery and vein in the body led directly to the heart, for example, the heart would be swamped in a vast tangle of blood vessels. Instead, a few large central vessels divide and redivide into smaller branches. Physically, the resistance to flow or skeletal strength are reduced when the vessels coalesce or the skeletal rays are fused. Biologically, the smaller branching vessels help animals survive damage and aid their development and growth." (Foy and Oxford Scientific Films 1982:24)
Learn more about this functional adaptation.
Sea urchins minimize the distance materials must be transported from a central point due to their radiating shape.
"If you let a drop of ink fall on a piece of paper, the splash pattern that results looks rather like a sea urchin. If you drop water into a bowl of liquid and photograph the moment of impact with high-speed equipment, the coronet shape formed at the surface resembles a sea anemone. Yet another of the basic shapes of life - the explosion, or radiating shape - repeats the forms taken by falling drops of water. Radiating shapes occur wherever numerous lines fan outwards from a single central point - whether in a flat plane, as with a starfish, or in three dimensions, as with a sea urchin. The plant kingdom is full of radiating shapes: the majority of flowers have this form, and many plants grow leaves that radiate directly from a stem base; but there are many examples in the animal kingdom as well. Radiating lines, as a construction design, have two useful attributes: they minimize the distance between the centre and the outlying points, and they provide great scope for increasing the surface area of an organism…The first of these qualities is most convenient in cases where materials must be transported rapidly from the centre to outer points or vice versa. There is a disadvantage, however. If there are a lot of outlying points, the lines tend to become overcrowded around the centre (diagram a). One way to overcome this problem is to develop branching patterns, to reduce the total length of travel and the congestion of lines at the centre (diagram b). If each artery and vein in the body led directly to the heart, for example, the heart would be swamped in a vast tangle of blood vessels. Instead, a few large central vessels divide and redivide into smaller branches. Physically, the resistance to flow or skeletal strength are reduced when the vessels coalesce or the skeletal rays are fused. Biologically, the smaller branching vessels help animals survive damage and aid their development and growth." (Foy and Oxford Scientific Films 1982:24)
Learn more about this functional adaptation.
- Foy, Sally; Oxford Scientific Films. 1982. The Grand Design: Form and Colour in Animals. Lingfield, Surrey, U.K.: BLA Publishing Limited for J.M.Dent & Sons Ltd, Aldine House, London. 238 p.
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Molecular Biology and Genetics
Molecular Biology
Statistics of barcoding coverage
Barcode of Life Data Systems (BOLD) Stats
| Specimen Records: | 2,417 | Public Records: | 720 |
| Specimens with Sequences: | 1,621 | Public Species: | 132 |
| Specimens with Barcodes: | 1,428 | Public BINs: | 148 |
| Species: | 292 | ||
| Species With Barcodes: | 230 | ||
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Barcode data
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Locations of barcode samples
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