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Category: Invertebrates



The structure of flatworms (flat) reflects their physiology – they have no body cavity other than a gut in most cases and rely on diffusion for respiration. Traditional zoology texts have divided this phylum into Turbellaria (Planarians) and three parasitic groups: Cestoda (tapeworms), Trematoda (flukes), and Monogenea (fish parasites), though scientific articles may present a more phylogenetically nuanced picture. For example, recent molecular research suggests that Turbellarians may have arisen polyphyletically (from two independent groups from different ancestral groups). Parasitic flatworms are a significant public health concern worldwide but are sometimes employed for beneficial purposes, such as controlling mosquito and invasive snail populations.




Data & Facts

Scientific Classification
Kingdom - Animalia
Phylum - Platyhelminthes
Class - Cestoda
Class - Monogenea
Class - Trematoda
Class - Turbellaria

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Interesting Animal Facts

Cephalopods: Masterminds of the Ocean.

Octopi, cuttlefish, and squids - all cephalopods - have been observed engaging in amazing feats of intelligence (perhaps unsurprising, as cuttlefish and octopuses have the highest brain-to-body mass of all invertebrates). Their suction-cup covered arms are dexterous, and octopuses have been observed putting them to use throwing rocks, opening screw-top jars, even picking up and gathering coconut shells to build fortresses for themselves. Squids, for their part, have been observed hunting cooperatively and are able to communicate with one another via color changes, patterns, and flashing to one another - sometimes using different sides of their bodies to broadcast different signals to multiple squids! Just how smart are they? As they are typically elusive and so very different from humans, we aren’t sure yet - but we do know the question is not “Are they intelligent?” but “How intelligent are they?”

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