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Introduction
Invertebrates are animals that neither posses nor develop a vertebral column, derived from the notochord. These include all animals apart from the subhylum Vertebrata.
Invertebrates are animals with no backbone. 97 of the animals are invertebrates among the estimated 2.16 million animal specie. Invertebrates exist about anywhere. These have been found in the driest deserts, high reaches of atmosphere and canopies of wettest rainforests. They also exist in the frozen antartica or under the deepest oceans.
Wheather batting aaway irritating flies, unearthing a worm or admiring the complexity of a spiders web and much more, all these animals are invertebrates.
Invertebrates are so many that its almost impossible to count them all. There are so many invertebrate animal species of diffrent shapes an sizes that help is in many ways and are vital to our survival.
Types of Invertebrates
Terrestrial invertebrates involve these groups
• Insects
• Spiders
• Worms
• Slaters
• Land hoppers
• Centipedes
• Millipedes
• Velvet worms
Freshwater and marine invertebrates
Characteristics of invertebrates
By now as you know what invertebrates are, lets get to know about their characteristics.
• All invertebrates do not have a spinal cord or vertebal column, instead, most of them posses an exoskeleton that encompasses the entire body.
• Normally, these are tiny and dont grow very large.
• Do not possess lungs since they respire through their skin.
• Since they cannot produce their own food, Invertebrates are heterotrophic.
• Reproduction occurs through fission.