Pheromones
Have you ever wondered how different species know when to mate and who to mate with? How can they tell the difference between someone of the same sex, much less whether another organism is of the same species? This can be answered by chemical signals kn own as pheromones. Pheromones are unique and highly specific chemical signals produced by an organism that signals its presence to other members of the same species. Each organism have different pheromones they release during mating that helps them to id entify each other and start the process of mating. Pheromones come not only in forms of sex attractants, but also as alarm pheromones, aggregation pheromones, and dispersion pheromones(1).
How do we know that such a chemical exists in organisms? In 1956, German scientists were able to identify the first ever pheromone in silkworm moths. After 20 years of research and over half a million female moths later, they were able to extract a pecu liar compound from certain glands located on the tip of the abdomen. When even a small amount of this substance was exposed to male moths, they would begin to beat their wings madly in a iflutter dancei. This indicated that they had detected the powerfu l sex attractant from the females that caused this type of behavior. After extracting extraneous matter and purifying the substance, scientists ended up with the first ever chemically pure pheromone. Since then, various other organisms have been studied and more is understood about the effects of pheromone, but not much is known about how pheromones work in more complex vertebrates such as humans.
The next logical question to ask is how are these chemical signals recognized? Studies have shown that pheromone is first recognized by the chemical receptors in the vomeronasal organ (VNO) and olfactory bulbs located in the nose; signals are then sent t o the hypothalamus of the brain. In an experiment conducted on virgin male mice where their VNO was removed, the mice were found to generally not mate with receptive females, even if the maleis olfactory nerves were not damaged. This showed that the VNO s are needed in order start certain chains of reactions already programmed in the brain. Further studies show that when male mice have begun to associate sexual activity with other cues from females, including smells they become less dependent on the VNO s.
A good number of these synthetic pheromone based products effects are hyped in order to attract desperate folks out there. On the other hand, some highly effective pheromone based formulas still exist.
Lewis and Clark were very successful people however their greatest success was only achievable with the help of Native Americans. April 1803 President Thomas Jefferson purchased uncharted territory from france. Jefferson always had liked the idea of western expansion so when he got the chance he took it. Jefferson pushed for approval to head an exploration of the Louisiana Purchase, and in 1803 it was approved. Jefferson had named Meriwether Lewis the leader and William Clark as his associate it wouldn't be until their first winter during the exploration that sacajawea would come into the picture . However Jefferson did not announce publicly that the U.S. had purchased eight hundred and sixty eight thousand square miles of land for fifteen million dollars until July .Lewis and Clark’s journey began near St.Louis, Missouri May 1804. Most days of the exploration had harsh conditions or at least one challenging obstacle to get around.For example during the exploration the hundred and forty six days spent in North Dakota, they experienced harsh temperatures below zero. This vast amount of uncharted land would become thirteen of the the states we know today. This expedition would discover a hundred and twenty two new animals, and a hundred and seventy eight plants, the expedition took eight hundred and sixty three days over a length of seven thousand six hundred and eighty nine miles, and at the cost of thirty eight thousand seven hundred and seventy two dollars and twenty five cents. Lewis and Clark’s Expedition would not have been as successful as it was without the help of George Drouillard, Sacajawea, and the Native American tribes they encountered. These Native Americans helped provide shelter, food, knowledge, and artifacts ...
Geographic discovery was an essential goal that Jefferson set for the expedition. Lewis and Clark recorded a wealth of scientific knowledge as they noted significant geographic features, made detailed route maps, and recorded their observations of longitude and latitude. Lewis performed most the astronomical duties and Clark charted the course and drafted expedition maps.
The Lewis and Clark Expedition, also known as the Corps of Discovery Expedition, was the crowning achievement of Thomas Jefferson’s Presidency. Without the Lewis and Clark Expedition, the United States may never have expanded west. The expedition set out from outside St. Louis in May of 1804. During that summer and into the fall, the explorers paddled upstream, northwest on the Missouri River to Fort Mandan where the Corps of Discovery set up camp, wintered, and prepared for the journey to the Pacific. This expedition was extremely important for the new nation because on their journey, the Corps of Discovery did find a water route to the Pacific Ocean. They documented and cataloged the geography, as well as new flora and fauna they encountered, resulting in an extensive journal of new scientific information. They also established diplomatic and trade relations with the Native American Tribes they encountered along the way.
Have you ever wondered what an expedition would look like? How it would feel to actually do one in the early 1800’s? Lewis and Clark lived through many attempted ones and actually did one themselves and their story has been told for hundreds of years. Lewis and Clark were very well known expeditioners. Their real names are actually Meriwether Lewis and William Clark. Thomas Jefferson was interested in the Western land, between the Mississippi River and the Rocky Mountain. The Louisiana Purchase happened which gave Jefferson an opportunity and a reason to fulfil his dreams onto Westward land. Lewis began to prepare for this expedition. He was interested in the length of rivers and location, geographical features, economic and agricultural development and much more. It took Jefferson, Lewis, and Clark many hard years of preparation to get everything ready for the trip. They knew that it wasn’t going to be a safe nor easy trip, but the intriguing sound of the trip and what the Westward land could hold was unbearable. After years of planning, stressing, and getting ready for the expediton, Lewis set out on August 31, 1803 in his keelboat, flat-bottomed, large dugout “canoe”.
The goals of this expedition, as outlined by President Jefferson, were to study the Native American tribes living in the area as well as the plants, animals, geology and terrain of the region. The expedition was also to be a diplomatic one and aid in transferring power over the lands and the people living on them from the French and Spanish to the United States. In addition, President Jefferson wanted the expedition to find a direct waterway to the West Coast and the Pacific Ocean so westward expansion and commerce would be easier to achieve in the coming years.
Some individuals have developed different traits to help them in the process of intra-sexual competition. The organisms with more distinctive traits have greater reproductive success. More genes of those traits are then ‘selected’ and are passed onto the offspring of the organisms. Throughout time variability in these traits becomes
According to an MSNBC survey, 53% of single people find a great smile to be the most attractive feature in a potential mate. Another percentage of single people surveyed that flattery is the best was to attract someone (Dating/Relationship Statistics). Psychologists at the University of Pennsylvania studied data from over 10,000 speed daters and found that most people make a decision regarding a person’s attraction within three seconds of meeting (Penn New ).
Scent is part of the five senses that are developed when an infant is still in the mother’s womb. It is processed by a part of the brain that correlates with memory, so at a young age an infant could differentiate who their mother is by scent. Odor is a sign and olfactory condition (Waskul & Vannini, 2008). As someone gets older they begin to develop scents they like and dislike. There are also scents that people find attractive and unattractive. When meeting another individual for the first time a human’s first instinct is to smell them without realizing it. For instance, have you ever sat by someone or hugged someone who smelled good or bad? If so, many people tend to associate the scent with attractiveness or unattractiveness depending on the level of smell. There have been many studies indicating that there is a strong correlation between odor and attractiveness. Although the scent is a universal and an undetectable smell it can influence the level of perceived attractiveness of another person.
Fireflies talk to each other using light signals, male fireflies fly around giving off species-specific patterns to let the females know that he ...
This paper describes flirtation today and how flirtation has evolved. Based on several forms of research, this paper will explain studies concerning how people flirt, why they do it, and the theories behind it. It is stated that not only does flirting increase your chances of getting a date; it also improves your interpersonal skills at the work place. Researchers also came to the conclusion that there are many forms of flirting, some you may have never thought to be flirting cues. For example, the occasional hand to the shoulder move when you think someone has said something funny, may be perceive as a flirtatious action. Lastly, this paper will discuss effective and ineffective flirting styles along with how men and women’s views on flirting vary from each other.
The majority of the brain areas affected are in the limbic system. The limbic system is associated with emotional behavior, long term memory, and olfaction. Your sense of smell is the first and most primitive sense you use when you are born. It helps newborns to recognize their parents. Our sense of smell is intertwined with our memories formed in our
not even be attracted to their looks, but you feel compelled to talk to them or
In life as well as literature, some sought to display their sensibility by weeping and fainting and blushing and reacting extravagantly to scenes of poverty or illness. Sensibility was understood as a capacity intimately connected with the physical nature of nerves. Essential to its existence was its operation on the body as well as the mind. Thus a propensity to blush and weep might be taken as evidence that the weepers, full of sensibility, loved their neighbours as themselves. (Spacks 141)
making them less prone to attack by fungi and insects. The use of sex pheromones