The Phylum Arthropoda
This is the largest and most successful of the animal phyla, with over 1 000 000 species identified to date and an estimated 1 000 000 000 000 000 000 (1 quintillion) individuals alive today. Some scientists estimate that there are over 200 million insects for each single person. That's just insects alone, and doesn't include the millions of spiders, crustaceans, millipedes, centipedes, that make up the phylum Arthropoda.
Arthropods are the most easily identifiable of all the animals, as they all share several things in common that no other animals share. First, all arthropods are protected by a hard exoskeleton (outer skeleton). This exoskeleton protects the organs, gives support for the body, and allows for efficient movement. However, because the exoskeleton cannot grow, it must be shed to allow for the organism to grow.
All arthropods have segmented bodies divided into a head, thorax, and abdomen. In some cases, such as with the lobster, the head and thorax are fused together. This is called a "cephalothorax". Arthropods also have jointed appendages.
Arthropods are very diverse phylum, and therefore can move in a wide variety of ways. They can walk, crawl, climb, hop, fly, glide, swim, skate, and dive.
Arthropods can be found on every continent and in every ocean, from the harsh climate of Antarctica to the dryness of the desert to the wetness of the rainforests, and even to the darkness of the ocean's depths. They can be found in ponds, on plants, in and on other animals, and even in your own house!
Arthropods are the most easily identifiable of all the animals, as they all share several things in common that no other animals share. First, all arthropods are protected by a hard exoskeleton (outer skeleton). This exoskeleton protects the organs, gives support for the body, and allows for efficient movement. However, because the exoskeleton cannot grow, it must be shed to allow for the organism to grow.
All arthropods have segmented bodies divided into a head, thorax, and abdomen. In some cases, such as with the lobster, the head and thorax are fused together. This is called a "cephalothorax". Arthropods also have jointed appendages.
Arthropods are very diverse phylum, and therefore can move in a wide variety of ways. They can walk, crawl, climb, hop, fly, glide, swim, skate, and dive.
Arthropods can be found on every continent and in every ocean, from the harsh climate of Antarctica to the dryness of the desert to the wetness of the rainforests, and even to the darkness of the ocean's depths. They can be found in ponds, on plants, in and on other animals, and even in your own house!