Category: Invertebrates
The Arachnid class is comprised of over 100,000 described species and includes such familiar organisms as spiders, scorpions, harvestmen, ticks, and mites All arachnids have eight legs, though the front pair of legs is sometimes reduced and converted to sensory apparatus. They never have antennae or wings. Almost all arachnids are terrestrial as well as carnivorous. Arachnids feed by secreting digestive juices onto their dead and/or immobilized prey, which turns their prey into a broth of nutrients that can then be sucked up into their mouth and stomach.
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?”
Learn more >>