Arthropoda
Arthropods are animals belonging to the phylum Arthropoda, which is the largest of all phyla in the Animal Kingdom, with more than one million species, making them almost 80% of the whole kingdom. These include insects, arachnids, crustaceans and many more, most of which are quite small, the biggest being the Japanese Spider Crab with a leg span of 3.5 meters and the smallest being the microscopic Plankton.
*Characteristics:
- Segmented Body.
- Exoskeleton. This is a hard outer body covering which protects the internal organs.
- Jointed legs. The name ‘arthropod’ comes from Latin, meaning ‘joints’.
- Specialized mouth parts.
- Compound eyes.
- Nervous system consisting of a brain.
- Sexes mostly separate.
- An open circulatory system.
*Classification:
Subphyla:
Arachnida is a subphylum of Arthropoda, consisting of over 100 000 species, many of them being parasites which can carry disease. They are found in all environments, and mostly have eight legs, which is a feature, together with the fact that they do not have wings or antennae, often used to distinguish them from the other subphyla, though there are exceptions. They include spiders, scorpions, ticks and mites. Their bodies are divided up into three parts: the cephalothorax, the opisthosoma and the thorax, and use a type of lung for gas exchange. Most Arachnids are carnivorous, and eat pre-digested insects and other small animals. They reproduce using internal reproduction usually lay eggs, except for the scorpion which bears living young. The word ‘Arachnid’ comes from the Greek word ‘Arachne’ meaning ‘spider’.
Crustacea is a large subphylum of Arthropoda, consisting of almost 52 000 described species, including animals like crabs, lobsters, shrimp and barnacles. The majority of these are aquatic, living in marine or fresh water environments, though some have adapted to living on land like some crabs and woodlice. Most crustaceans are relatively small, though there are some exceptions. All of them have a hard, strong exoskeleton, divided into two parts, which has to be shed in order to allow the animal itself to grow. They have a large circulation system, where blood is pumped around the body by the heart. Only some crustaceans have sexes separate, and those that are usually mate seasonally and lay eggs. The study of Crustacea is called carcinology.
Diplopoda is a class, belonging to the subphylum of Arthropoda Myriapoda, consisting of about 10 000 species of animals which have two pairs of legs for each body segment and are often known as Millipedes. Hence the name, they do not have one thousand legs.
Spider monkey’s live in the tropical rain forrest and are best known for their incredible prehensile tails. I think it goes without saying that their tails adapted to have dermal ridges that hold and grab on to much tighter than any other prehensile tail in the animal kingdom because they lack functional thumbs, and the tails act as fingertips in replacement. Generally speaking, they hang out in Central and South America but sometimes show up as far away as Mexico. Their epic prehensile tails, long arms and teeny13.25 pound bodies allow them to feast high up in the trees on fruits, leaves, bird eggs and spiders. Although their interaction with the environment is interesting, so is their relationship with one anot...
Chelicerae are a pair of appendages that the spider uses to seize and kill its prey. The chelicerae are above the mouth opening and just below the spider's eyes. Each chelicera ends in a hard, hollow, pointed claw, and these claws are the spider's fangs. An opening in the tip of the fang connects with the poison glands. When the black widow stabs an insect with its chelicerae, poison flows into the wound and paralyzes or kills the victim.
The two other surviving species of monotremes are Tachyglossus aculeatus, the short-beaked echidna, and Zaglossus bruijni, the long-beaked echidna. Echidnas range throughout Australia and New Guinea as well as islands adjacent to both land masses (Collins 17). Both species have characteristic modified hairs that function as spines (Dawson 10-12). T. aculeatus is a stocky animal (3-5kg) with a small head and pointed snout (Dawson 10-11). Z. bruijni is larger than T. aculeatus (~10kg) and has a downward curving snout (Dawson 11-12). The snouts and tongues of T. aculeatus and Z. bruijni are ideal for diets of termites, ants, and earthworms (Dawson 10-12).
Fox, R. 2001. Invertebrate Anatomy OnLine: Artemia Franciscana. Lander University. http://webs.lander.edu/rsfox/invertebrates/artemia.html, retrieved February 13, 2011.
There are nearly one million species of insects known. Insects are defined by having six legs and a body divided into three segments: head, thorax, and abdomen. Chitin is an organic material that makes up an insects exoskeleton. There are three life cycles of insects, ametabolous or incomplete and paurometabolous or gradual, and homotabolous or complete metamorphosis. These life cycles are important in the aging of insects for aiding in legal investigations, (Houck and Siegel. Entomology).
When dinosaurs ruled the Earth spiders weaved their lives beneath them. When the dinosaurs became extinct spiders adapted and are still living with us today. Their only real enemy and threat to their existence is Man.
.... (2011). A New Arthropod Jugatacaris agilis n. gen. n. sp. from the Early Cambrian Chengjiang Biota, South China. Journal of Paleonotology, 85(3), 567-586. doi:10.1666/09-173.1
You probably think horseshoe crabs are crustaceans, but you’d be wrong. They actually aren’t crabs at all, and there’s more about the horseshoe crab that you wouldn’t believe. This weird-looking marine animal survived two mass extinctions and lived in the Ordovician Period.
Protists are not animals, plants, or fungi. They have their very own kingdom called The Kingdom Protista. Protists are a very diverse group. There are over 200,000 of them. They get classified into three main groups, and then get classified further into phyla Protists can be found in everyday surroundings, and they have a big impact on all organisms on Earth.
Long ago, there was lots of spiders that lived in the woods. All the spiders had 8 legs except one spider.The Spiders had 8 legs because they worked very hard. The other spider was just lazy and didn't want to do anything.
Spiders are seen as vicious disgusting monsters. Everytime you see a spider, we think of getting rid of them. In other cultures spiders are a symbol of peace and revered as a god. Some cultures that think of highley of this eight leg insect are Ancient Egypt, Greece, Rome, Africa, and Peru, and Asia.
THEY CAN HAVE AS MANY AS 140 (SURPRISINGLY MULTIPURPOSE) LEGS. What what they do with them is far more impressive than walking or swimming. Some legs act as antennae that help them find food, while others create a water current to direct food toward their mouth. Females have capsules on some of their legs to carry eggs. Some triops have lobe or leaf-like extensions on their legs that function similarly to gills, allowing them to breathe.
Ants, Little but Mighty. What is an ant? Ants are insects, they have six legs and each leg has three joints. Ants legs are very strong.
Insect, small, air-breathing animal characterized by a segmented body with three main parts—head, thorax, and abdomen. In their adult forms, insects typically have three pairs of legs, one pair of antennae, and in most instances, two pairs of wings. Insects rank among the most successful animals on Earth. About one million species of insects have been identified so far, which is about half of all the animals known to science. That is why for every pound of human on the earth there are 10 pounds of insects. So that is why there are many reasons why insects are so successful, their exoskeleton, their size, their body function, the way they reproduce, and their development of metamorphosis.