Horny insects.Insects are arthropods, having a hard exoskeleton, a three-part body (head, thorax, and abdomen), three pairs of jointed legs, compound eyes, and two antennae. The head holds, mainly, the large compound eyes, the antenna (feelers), and the mouthparts. The legs (and wings, if applicable) are attached to the thorax. On most Insects, the abdomen is not an outstanding feature composed of 11 segments. On grasshoppers, there is a large round disc on the first segment next to the thorax. It is called a tympanum and is the grasshopper's ear. And on each abdominal segment, there is a small breathing hole called the thoracic spiracle.
Insects are the most diverse group of animals on the planet. There are approximately 2,200 species of praying mantis, 5,000 dragonfly, 20,000 grasshopper, 82,000 true bug, 120,000 fly, 110,000 bee, wasp ant and sawfly, 170,000 butterfly and moth, and 360,000 beetle species described to date. Estimates of the total number of current species, including those not yet known to science, range from two million to fifty million, with newer studies favouring a lower figure of about six to ten million. With over a million described species more than half of all known living organisms with estimates of undescribed species as high as 30 million, insects potentially represent over 90% of the differing life forms on the planet. They are most diverse at the equator and their diversity declines toward the poles. Insects may be found in nearly all environments on the planet, although only a small number of species occur in the oceans, a habitat dominated by another arthropod group, the crustaceans.
Insects possess segmented bodies supported by an exoskeleton, a hard outer covering made mostly of chitin. The segments of the body are organized into three distinctive but interconnected units, or tagmata; a head, a thorax, and an abdomen. The head supports a pair of sensory antennae, a pair of compound eyes, if present, one to three simple eyes, if present, ("ocelli") and three sets of variously modified appendages that form the mouthparts. The thorax has six segmented legs (one pair each for the prothorax, mesothorax and the metathorax segments making up the thorax) and two or four wings (if present in the species). The abdomen (made up of eleven segments some of which may be reduced or fused) has most of the digestive, respiratory, excretory and reproductive internal structures...
Insects are the most diverse group of animals on the planet. There are approximately 2,200 species of praying mantis, 5,000 dragonfly, 20,000 grasshopper, 82,000 true bug, 120,000 fly, 110,000 bee, wasp ant and sawfly, 170,000 butterfly and moth, and 360,000 beetle species described to date. Estimates of the total number of current species, including those not yet known to science, range from two million to fifty million, with newer studies favouring a lower figure of about six to ten million. With over a million described species more than half of all known living organisms with estimates of undescribed species as high as 30 million, insects potentially represent over 90% of the differing life forms on the planet. They are most diverse at the equator and their diversity declines toward the poles. Insects may be found in nearly all environments on the planet, although only a small number of species occur in the oceans, a habitat dominated by another arthropod group, the crustaceans.
Insects possess segmented bodies supported by an exoskeleton, a hard outer covering made mostly of chitin. The segments of the body are organized into three distinctive but interconnected units, or tagmata; a head, a thorax, and an abdomen. The head supports a pair of sensory antennae, a pair of compound eyes, if present, one to three simple eyes, if present, ("ocelli") and three sets of variously modified appendages that form the mouthparts. The thorax has six segmented legs (one pair each for the prothorax, mesothorax and the metathorax segments making up the thorax) and two or four wings (if present in the species). The abdomen (made up of eleven segments some of which may be reduced or fused) has most of the digestive, respiratory, excretory and reproductive internal structures...
                    |
No comments:
Post a Comment