Report of the Committee on Paleoecology, 1935-1936: Presented at the Annual Meeting of the Division of Geology and Geography, National Research Council, May 2, 1936 (1936) / Chapter Skim
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The Oecology of Porifera, and Possibilities of Deductions As to the Paleoecology of Sponge from their Fossils - M. W. de Laubenfels
The Oecology of Porifera, and Possibilities of Deductions As to the Paleoecology of Sponge from their Fossils - M. W. de Laubenfels
Pages 44-54
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From page 44... ...
We have numerous observations of sponges growing in aquaria but having no other nourishment than what they may obtain from the current of water that is being introduced into said aquaria. The fact that sponges regularly die when kept in stagnant water may indicate that in such the oxygen supply becomes exhausted and that they perish from suffocation, but the fact that they can live in aquaria where they are not fed otherwise than by that which is brought in by the current is significant of a nutritive as well as respiratory importance.
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From page 45... ...
As noted below, the deposition of silt may also account for oscular chimneys. Since such deposition is frequently also associated with relatively calm waters something can be said as to the lack of current indicated by such morphology, Sponges that live amid rapid currents always lack pronounced surface elevations.
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From page 46... ...
Such morphology in a fossil sponge very probably indicates that when still alive the animal in question was bathed with current of uniform direction, and at a depth to be measured at least in terms of hundreds of meters. Many calcareous sponges or Calcispongiae also have a cylindrical form with the inhalent openings on' the outside and the exhalent openings apical.
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From page 47... ...
The indications are that during the interval which has elapsed since the region that is now Puget Sound sank below the sea level, only a score or so of exceptionally migratory species has had time to work in. It is tempting therefore to assume if in an horizon there are found numerous different sorts of fossil sponges, that the locality in question had been continuously favorable for the growth of sponges for many thousands of years at the time 1*
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From page 48... ...
It is frequently stated in the earlier works on sponges that such species are characteristic of the tropics or warmer waters, and not at all of the colder portions of the earth. Further investigation indicates that a more nearly correct statement would be as follows: in warm waters those sponges lacking mineral skeletons are more numerous in comparison to the others, whereas in colder waters the latter are more numerous in comparison to the former.
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From page 49... ...
In brackish water no sponges seem to thrive and not many species of any sort occur» but those which arc found in such localities are divided among the-marine and fresh water sponges, the tiro sorts occurring side by side. The relationship between bathymetric pressure and the occurrence or absence of sponge types and any effect on the morphology of individual sponges cannot be considered apart from the probably more important question of light.
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From page 50... ...
It is, for instance, noteworthy that siliceous sponges thrive in the vicinity of coral reefs where there is a considerable lack of siliceous material on the bottom or in the surrounding vicinity, and conversely that calcareous sponges thrive especially well on granite shores where there is no limestone very near. Since (for otherrreasons noted above)
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From page 51... ...
There is such widespread assumption that much is known about the nutrition- of sponges that some remarks on this question may be in order at the present time. Many, perhaps the most, of the experiments bearing on the so-called nutrition of sponges have involved introducing carmine powder, indigo, India ink, and other such readily observed minute particles of material into the organism in question.
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From page 52... ...
There are exceedingly numerous instances of interrelationships between arthropods end sponges. Many kinds of insect larvae eat fresh water sponges, or live im them, thereby securing shelter.
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From page 53... ...
There are fairly numerous anthozoans which grow perched upon sponge tissues, as for instance those on the rooting tufts of the hexactinellid sponge Hyalonema, and the anemones of the genus Parazoanthus which may grow upon shallow water ramose sponges. Porifera, moreover, very frequently grow upon dead coral skeletons.
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From page 54... ...
little evidence is available from references to polyphyletic fossil faunas bears out the theory that the ages have witnessed little change in the methods ifaereby sponges react to their environments. It appears that in the past Porifera occurred in much the same environments as at present, and lived similar lives.
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