Adaptation Project. The arthropods constitute over 90% of the animal kingdom and are classified in the phylum Arthropoda.: There are more arthropods than any other group of invertebrates. And, considering that 95 percent of all animals are invertebrates, that makes arthropods truly the must abundant group. This is how the whole group is classified: * an exoskeleton (a skeleton on the outside of the body) * body divided into distinct parts * jointed legs and appendages * bilateral symmetry (both sides …showed first 75 words of 727 total…

…showed last 75 words of 727 total…away on a silk dragline and playing dead on the ground. Identifying Redback Spiders. Female Redback Spider, from below - note the characteristic orange-red hourglass shaped marking underneath. Photo: © A Healy. * Black to brown pea-sized spiders with a median scarlet-red to orange-yellow stripe on the back of the abdomen. The stripe is often broken and outlined with fine white markings * Slender black-brown legs * Characteristic orange-red ' hour-glass' shaped marking underneath the abdomen