So far from being ‘typically sedentary animals’, as they are described in textbooks-the victims of chance and circumstance-it is now established that they can, or at least in some species, exercise some selection as to habitat, the movement being a directive locomo tion, carried out by amoeboid extensions of the ectosome. This discovery has an important bearing on our conceptions of the biology of sponges. Yellow tube sponges reproduce both sexually and asexually, with asexual reproduction typically occurring only when storms or other disturbances break off part. Movement in post-larval, and young sponges, he pointed out, had been recorded on several occasions but it was now apparent, for the first time, that even fully-grown individuals could change their position. He found that even the adults were capable of moving appreciable dis tances to secure a more favourable area for feeding. Burton had been asked to investigate some sponges growing on the filter-beds of the Society's Aquarium, as it was feared these might interfere with the circulation of the water. many can move to new locations by dissassembly-reassembly (see: chicken liver sponges climbing up turtle grass) most sponges canbe disaggregated and cells can. sponges also dont move while coelenterates do. Burton at a meeting of the Zoological Society on February 21. Why are coelenterates more advanced than sponges sponges are made up of individual cells. A NEW and valuable light was thrown on the vexed question of locomotion in sponges by Mr.
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