Arrowheads, which are ancient hunting tools, are often themselves ‘hunted’ for their interesting value both as artifacts and as art. Some of the oldest arrowheads in the United States date back 12,000 years. They are not very difficult to find. You need only to walk with downcast eyes in a field that has been recently tilled for the spring planting season, and you might find one.
Arrowheads are tiny stones or pieces of wood, bone, or metal which have been sharpened in order to create a tipped weapon used in hunting. The material is honed to an edge, usually in a triangular fashion, and is brought to a deadly tip. On the edge opposite the tip is a flared tail. Though designs vary depending on the region, purpose, and era of the arrowhead’s origin, the tails serve the same purpose. The tail of the arrowhead is meant to be strapped onto a shaft, which is a straight wooden piece such as a spear or an arrow. When combined, the arrowhead point and the shaft become a lethal projectile weapon to be thrown by arm or shot with a bow at prey.
Indian arrowheads are important artifacts that give archeologists (scientists who study past human societies) clues about the lives of Native Americans. By analyzing an arrowhead’s shape, they can determine the advancement of tool technologies among certain Native American groups. By determining the origin of the arrowhead material (bone, rock, wood, or metal), they can trace the patterns of travel and trade of the hunters. By examine the location of the arrowheads, archeologists can map out hunting grounds and other social patterns.
Arrowheads are commonly found along riverbanks or near creek beds because animals drawn to natural water sources to sustain life were regularly found drinking along the banks. For this reason, riverbeds were a prime hunting ground for the Native Americans. Now, dry and active riverbeds are prime hunting grounds for arrowhead collectors.
Indian arrowheads are tiny pieces of history that fit in the palm of your hand. They are diary entries in the life of a hunter. They are museum pieces that hide in the dirt. They are symbolic of the eternal struggle between life and death.
As used in paragraph 2, which is the best definition for projectile?
Fleas are perfectly designed by nature to feast on anything containing blood. Like a shark in the water or a wolf in the woods, fleas are ideally equipped to do what they do, making them very difficult to defeat. The bodies of these tiny parasites are extremely hardy and well-suited for their job.
A flea has a very hard exoskeleton, which means the body is covered by a tough, tile-like plate called a sclerite. Because of these plates, fleas are almost impossible to squish. The exoskeletons of fleas are also waterproof of fleas are also waterproof and shock resistant, and therefore fleas are highly resistant to the sprays and chemicals used to kill them.
Little spines are attached to his plate. The spine the flea scurries through an animal’s fur in – search of grooming pet tries to pull a flea off through the hair coat, these spines will extend and stick to the fur like Velcro.
Fleas are some of the best jumpers in the natural world. A flea can jump seven inches, or 150 times its own length, either vertically or horizontally. An equivalent jump for a person would be 555 feet, the height of the Washington Monument. Fleas can jump 30,000 times in a row without stopping, and they are able to accelerate through the air at an incredibly high rate – a rate which is over ten times what humans can withstand in an airplane.
Fleas have very long rear legs with huge thigh muscles and multiple joints. When they get ready to jump. They fold their long legs up and crouch like a runner on a staring block. Several of their joints contain a protein called resilin, which helps catapult fleas into the air as they jump, similar to the way a rubber band provides momentum to a slingshot. Outward facing claws on the bottom of their legs grip anything they touch when they land.
The adult female flea mates after her first blood meal and begins producing eggs in just 1 to 2 days. One flea can lay up to 50 eggs in one day and over 2,000 in her lifetime. Flea eggs can be seen with the naked eye, but they are about the size of a grain of salt. Shortly after being laid, the eggs begin to transform into cocoons. In the cocoon state, fleas are fully developed adults, and will hatch immediately if conditions are favorable. Fleas can detect warmth, movement, and carbon dioxide in exhaled breath, and these three factors stimulate them to emerge as new adults. If the flea does not detect appropriate conditions, it can remain dormant in the cocoon state for extended periods. Under ideal conditions, the entire life cycle may only take 3 weeks, so in no time at all, pets and homes can become infested.
Because of these characteristics, fleas are intimidating opponents. The best way to control fleas, therefore, is to take steps to prevent an infestation from ever occurring.
Based on information in the passage, the reader can understand that